diff --git "a/transcription.json" "b/transcription.json"
new file mode 100644--- /dev/null
+++ "b/transcription.json"
@@ -0,0 +1 @@
+[{"title": "Boyle\u2019s Law .txt", "text": "So in order to explain exactly how individual gas molecules behave, scientists came up with something called a kinetic molecular theory."}, {"title": "Boyle\u2019s Law .txt", "text": "And what this theory is is it's basically a bunch of assumptions that they make about gases that helps us understand how individual gas molecules interact."}, {"title": "Boyle\u2019s Law .txt", "text": "So the kinetic theory is used to explain the behavior of gases on a nanoscale level."}, {"title": "Boyle\u2019s Law .txt", "text": "Now, in order to look at the macroscopic level or explain gas behavior on a macroscopic level, much larger level, we have to look at something else."}, {"title": "Boyle\u2019s Law .txt", "text": "Now, scientists came up with different equations and formulas to explain macroscopic gas behavior."}, {"title": "Boyle\u2019s Law .txt", "text": "The first formula we're going to look at and discuss is called Boils Law."}, {"title": "Boyle\u2019s Law .txt", "text": "Now, Boils Law works under certain conditions."}, {"title": "Boyle\u2019s Law .txt", "text": "Now, if we have a constant temperature and constant number of moles or N constant number of molecules, then we can use something called Boils Law."}, {"title": "Boyle\u2019s Law .txt", "text": "And what Boils Law relates is it relates volume and pressure."}, {"title": "Boyle\u2019s Law .txt", "text": "And what it states is that volume is directly proportional to the inverse of one over P. Or said another way, volume is inversely proportional to one over P. And we can represent this as VP equals constant."}, {"title": "Boyle\u2019s Law .txt", "text": "In other words, if we rearrange this and multiply this by some constant, we get this formula."}, {"title": "Boyle\u2019s Law .txt", "text": "And what this basically says is that under these conditions of constant temperature and constant number of moles, v times p will always be a constant."}, {"title": "Boyle\u2019s Law .txt", "text": "So when B increases, p decreases, or when P increases, V decreases and so on."}, {"title": "Boyle\u2019s Law .txt", "text": "And our constant depends on the temperature and the number of moles."}, {"title": "Boyle\u2019s Law .txt", "text": "So if temperature increases or its temperature changes or N changes, this constant will also change."}, {"title": "Boyle\u2019s Law .txt", "text": "In other words, the number that you get when you multiply D times P will also change."}, {"title": "Boyle\u2019s Law .txt", "text": "Now, suppose we have some gas or some sample of gas."}, {"title": "Boyle\u2019s Law .txt", "text": "And suppose we have one set of conditions and a second set of conditions."}, {"title": "Boyle\u2019s Law .txt", "text": "So suppose I have the following."}, {"title": "Boyle\u2019s Law .txt", "text": "Suppose I have some container with pressure one and volume one."}, {"title": "Boyle\u2019s Law .txt", "text": "And I have the same container, but with a smaller volume and a different pressure."}, {"title": "Boyle\u2019s Law .txt", "text": "So one set of conditions and second set of conditions."}, {"title": "Boyle\u2019s Law .txt", "text": "Now, what this law does is it explains macroscopic phenomenon."}, {"title": "Boyle\u2019s Law .txt", "text": "Like, for example, why is it that when I take a balloon filled with air and I push it hard enough, it explodes?"}, {"title": "Boyle\u2019s Law .txt", "text": "Well, why did that occur?"}, {"title": "Boyle\u2019s Law .txt", "text": "Well, this can be explained by Boyle's Law and I'll show you in a second."}, {"title": "Boyle\u2019s Law .txt", "text": "Well, this equation can be rearranged in this format if we're dealing with two different sets of conditions."}, {"title": "Boyle\u2019s Law .txt", "text": "Notice that p times V will always give you a constant when you're talking about the same temperature and the same number of mole."}, {"title": "Boyle\u2019s Law .txt", "text": "So if I have one set of conditions p one times v one, that will give me a constant."}, {"title": "Boyle\u2019s Law .txt", "text": "And if I have the second set of conditions p two times v two, it will give me the same constant, right?"}, {"title": "Boyle\u2019s Law .txt", "text": "So I can set them equal."}, {"title": "Boyle\u2019s Law .txt", "text": "This guy is equal to the same constant that this number represents."}, {"title": "Boyle\u2019s Law .txt", "text": "So this is my equation for two sets of data or two sets of conditions."}, {"title": "Boyle\u2019s Law .txt", "text": "Now let's look at this picture."}, {"title": "Boyle\u2019s Law .txt", "text": "Well, once again, why is it that a balloon explodes?"}, {"title": "Boyle\u2019s Law .txt", "text": "Well, when the balloon is when you're not compressing the balloon, when you're just dangerous up, it has a certain pressure and a certain volume."}, {"title": "Boyle\u2019s Law .txt", "text": "When you take it in your hand and you begin squeezing it, you begin decreasing the volume."}, {"title": "Boyle\u2019s Law .txt", "text": "Boils law states that if you decrease volume, pressure must increase because our constant remains the same."}, {"title": "Boyle\u2019s Law .txt", "text": "And that means pressure will begin to increase and the ball or the balloon will pop when the pressure is large enough for it to burst open and pop."}, {"title": "Boyle\u2019s Law .txt", "text": "And that's exactly why balloon, when squeezed, will eventually pop."}, {"title": "Boyle\u2019s Law .txt", "text": "So let's look at ventral sensation."}, {"title": "Boyle\u2019s Law .txt", "text": "Suppose that this is our balloon and this is our compressed balloon."}, {"title": "Boyle\u2019s Law .txt", "text": "Well, our gas molecule in this condition are further in part than they are in this condition."}, {"title": "Boyle\u2019s Law .txt", "text": "And that means if they're further apart here, they will make less collisions than here."}, {"title": "Boyle\u2019s Law .txt", "text": "And that means that there are less collisions."}, {"title": "Boyle\u2019s Law .txt", "text": "Less of the molecules are colliding with the walls."}, {"title": "Boyle\u2019s Law .txt", "text": "And so with less collisions, that means we have less pressure."}, {"title": "Boyle\u2019s Law .txt", "text": "So the bigger the volume, the smaller the pressure."}, {"title": "Boyle\u2019s Law .txt", "text": "So once again, we see that we can use the kinetic theory to explain nanoscopic or nanoscale behavior of these molecules."}, {"title": "Boyle\u2019s Law .txt", "text": "And once again, the kinetic theory explains boiler's law."}, {"title": "Boyle\u2019s Law .txt", "text": "A smaller volume means less room to navigate and increase in number of collisions."}, {"title": "Boyle\u2019s Law .txt", "text": "This increase in collisions will increase our pressure because by definition, pressure is forced per unit area."}, {"title": "Boyle\u2019s Law .txt", "text": "And if we have more molecules hitting the walls, we have more force and so a higher pressure."}, {"title": "Boyle\u2019s Law .txt", "text": "So this is Boyle's Law and Boyle's Law is used to explain macroscopic behavior."}, {"title": "Boyle\u2019s Law .txt", "text": "So let's examine the graphs of Boyle's Law or a graph of Boyle's Law."}, {"title": "Boyle\u2019s Law .txt", "text": "Now, we can have two graphs."}, {"title": "Boyle\u2019s Law .txt", "text": "We can graph volume and pressure."}, {"title": "Boyle\u2019s Law .txt", "text": "Or we can grab volume and one over pressure."}, {"title": "Boyle\u2019s Law .txt", "text": "So let's graph this guy first."}, {"title": "Boyle\u2019s Law .txt", "text": "So recall that I said that volume is inversely proportional to one over P. Now mathematically what that means is we have this type of a graph in which as we increase our volume, our pressure decreases."}, {"title": "Boyle\u2019s Law .txt", "text": "Or if we decrease our volume, decrease that volume in the balloon, our pressure will begin to increase."}, {"title": "Boyle\u2019s Law .txt", "text": "If we continue to increase or decrease the volume, that pressure will begin to increase exponentially, right?"}, {"title": "Boyle\u2019s Law .txt", "text": "And that's what this represents."}, {"title": "Boyle\u2019s Law .txt", "text": "Now instead, suppose that I graph volume over one over P. Well, how would that look?"}, {"title": "Boyle\u2019s Law .txt", "text": "Well, if I grab the volume over one over P, whenever this guy increases, this guy increases by the same ratio amount."}, {"title": "Boyle\u2019s Law .txt", "text": "And that's because volume times pressure gives you a constant."}, {"title": "Boyle\u2019s Law .txt", "text": "If this increases by say, two times, then this must decrease by two times."}, {"title": "Boyle\u2019s Law .txt", "text": "That's why this guy is a straight line, the slope is constant, versus on this graph, the slope varies, it changes."}, {"title": "Boyle\u2019s Law .txt", "text": "And if you wanted to find the slope, you would have to use calculus and approximate it using lines tangent to any point on the line."}, {"title": "Boyle\u2019s Law .txt", "text": "Now, this is Boiler's law."}, {"title": "Boyle\u2019s Law .txt", "text": "Once again, boiler's Law explains macroscopic behavior gases versus the kinetic theory, which explains nanoscale behavior of individual molecules."}, {"title": "Structure of Atoms .txt", "text": "Today we're going to go into detail about atomic structure."}, {"title": "Structure of Atoms .txt", "text": "Now, all matter and mass is composed of very tiny units called atoms."}, {"title": "Structure of Atoms .txt", "text": "Everything we see, we touch, we feel is composed of atoms."}, {"title": "Structure of Atoms .txt", "text": "Now, atoms themselves are composed of nucleuses surrounded by electrons."}, {"title": "Structure of Atoms .txt", "text": "Now, a nucleus is composed of two types of particles called protons and neutrons."}, {"title": "Structure of Atoms .txt", "text": "Now, protons and neutrons have approximately the same weight."}, {"title": "Structure of Atoms .txt", "text": "A neutron is a tiny bit heavier than protons, but for all purposes we can approximate that these guys have the same exact mass."}, {"title": "Structure of Atoms .txt", "text": "Electrons, however, have a very small mass, much smaller than that of protons or neutrons."}, {"title": "Structure of Atoms .txt", "text": "In fact, it's 1800 times smaller than a proton or a neutron."}, {"title": "Structure of Atoms .txt", "text": "Now, if we look at this table and we look at their masses, a proton has one AMU, a neutron has one AMU."}, {"title": "Structure of Atoms .txt", "text": "Now, AMU is simply atomic mass unit."}, {"title": "Structure of Atoms .txt", "text": "We're going to discuss that in detail in another lecture."}, {"title": "Structure of Atoms .txt", "text": "But an electron has a mass of 5.5 times ten to negative four AMU that's much smaller than that of proton or a neutron."}, {"title": "Structure of Atoms .txt", "text": "The charge, however, of a proton, an electron has the same magnitude 1.6\ntimes ten to negative 19 Coulombs."}, {"title": "Structure of Atoms .txt", "text": "However, the sign of a proton is positive, while the sign of an electron is negative."}, {"title": "Structure of Atoms .txt", "text": "A neutron has VR charge."}, {"title": "Structure of Atoms .txt", "text": "It's a neutral charge."}, {"title": "Structure of Atoms .txt", "text": "Now let's look at the structure."}, {"title": "Structure of Atoms .txt", "text": "Now, in the illustration above, we see our atom."}, {"title": "Structure of Atoms .txt", "text": "Now, this whole guy is our nucleus."}, {"title": "Structure of Atoms .txt", "text": "And our nucleus is composed of two particles, protons and neutrons."}, {"title": "Structure of Atoms .txt", "text": "In this atom we have two protons and two neutrons."}, {"title": "Structure of Atoms .txt", "text": "The protons are quantitatively charged, while the neutrons are neutrally charged."}, {"title": "Structure of Atoms .txt", "text": "Now, the electron is found orbiting our atom, our nucleus."}, {"title": "Structure of Atoms .txt", "text": "And the distance between our nucleus and the electron is quite large."}, {"title": "Structure of Atoms .txt", "text": "And in fact, atoms are mostly composed of empty space."}, {"title": "Structure of Atoms .txt", "text": "And in fact, if our atom with the size of a football field, our nucleus will be the size of a marble."}, {"title": "Structure of Atoms .txt", "text": "So you can imagine that our entire atom, for the most part, is composed of empty space."}, {"title": "Structure of Atoms .txt", "text": "And that's because our electrons are very, very small and they orbit our nucleus at a very, very great distance compared to the size of the nucleus itself."}, {"title": "Structure of Atoms .txt", "text": "So what holds the nucleus or the protons and neutrons together?"}, {"title": "Structure of Atoms .txt", "text": "Well, the force that holds the nucleus together is called a nuclear force."}, {"title": "Structure of Atoms .txt", "text": "This is just one type of electrostatic force and it's a very strong force."}, {"title": "Structure of Atoms .txt", "text": "Now, once again, it's very important to understand the fact that due to the small size of our electrons orbiting our nucleus, the atom is composed mainly of empty space."}, {"title": "Dalton\u2019s Law on Partial Pressure .txt", "text": "Well, let's recall what the kinetic molecular theory tells us about the behavior of ideal gases."}, {"title": "Dalton\u2019s Law on Partial Pressure .txt", "text": "Well, it tells us two important things."}, {"title": "Dalton\u2019s Law on Partial Pressure .txt", "text": "First, gas molecules have no volume."}, {"title": "Dalton\u2019s Law on Partial Pressure .txt", "text": "And second, gas molecules exert no force on one another."}, {"title": "Dalton\u2019s Law on Partial Pressure .txt", "text": "That means if we had a system continuing containing two gas molecules, gas molecule A and gas molecule B, that means these two guys have no volume and they exert no force on one another, so they can't communicate."}, {"title": "Dalton\u2019s Law on Partial Pressure .txt", "text": "So in many different ways, molecule A is invisible to molecule B and molecule B is invisible to molecule A."}, {"title": "Dalton\u2019s Law on Partial Pressure .txt", "text": "And that leads directly into the following results pressure created by one gas molecule is independent of the pressure created by another gas molecule."}, {"title": "Dalton\u2019s Law on Partial Pressure .txt", "text": "In other words, the pressure that this gas molecule exerts on the walls of my system of my container is independent of what this guy exerts on my wall of the container."}, {"title": "Dalton\u2019s Law on Partial Pressure .txt", "text": "So to find the total pressure, my system of two gas molecules, I simply have to add up this pressure and this pressure."}, {"title": "Dalton\u2019s Law on Partial Pressure .txt", "text": "And that's exactly what B states."}, {"title": "Dalton\u2019s Law on Partial Pressure .txt", "text": "The total pressure of any system of gas molecules is equal to the pressure exerted by each an individual gas molecule."}, {"title": "Dalton\u2019s Law on Partial Pressure .txt", "text": "So p one plus p two plus all the way up to PM, assuming that my system is composed of M gas molecules."}, {"title": "Dalton\u2019s Law on Partial Pressure .txt", "text": "So this is simply a mathematical way of representing any series."}, {"title": "Dalton\u2019s Law on Partial Pressure .txt", "text": "So let's look at this system."}, {"title": "Dalton\u2019s Law on Partial Pressure .txt", "text": "So suppose we have a closed system of five gas molecules, two blue and three red."}, {"title": "Dalton\u2019s Law on Partial Pressure .txt", "text": "Now, we have two types of molecules and a total of five molecules."}, {"title": "Dalton\u2019s Law on Partial Pressure .txt", "text": "So my one type is blue."}, {"title": "Dalton\u2019s Law on Partial Pressure .txt", "text": "My second type is red."}, {"title": "Dalton\u2019s Law on Partial Pressure .txt", "text": "To find the total pressure of my system here, I would simply add up all the individual pressures."}, {"title": "Dalton\u2019s Law on Partial Pressure .txt", "text": "So five molecules altogether."}, {"title": "Dalton\u2019s Law on Partial Pressure .txt", "text": "So I add up to five molecules p blue one plus p blue two plus p red one plus p red two plus p red three."}, {"title": "Dalton\u2019s Law on Partial Pressure .txt", "text": "Now, I could also say that my p total is equal to the pressure due to blue gas molecules."}, {"title": "Dalton\u2019s Law on Partial Pressure .txt", "text": "This guy plus this guy plus the pressure due to red gas molecule or p one plus p two plus p three."}, {"title": "Dalton\u2019s Law on Partial Pressure .txt", "text": "Another way of saying this is the pressure due to my blue gas molecule is the partial pressure of my blue molecule and this guy is the partial pressure of my red molecule."}, {"title": "Dalton\u2019s Law on Partial Pressure .txt", "text": "So partial pressure refers to the pressure exerted by one type of gas molecule."}, {"title": "Dalton\u2019s Law on Partial Pressure .txt", "text": "In this case, a blue gas molecule or a red gas molecule in a mixture of gases."}, {"title": "Dalton\u2019s Law on Partial Pressure .txt", "text": "In this case, two types of gas molecules, red and blue."}, {"title": "Dalton\u2019s Law on Partial Pressure .txt", "text": "So another way of representing this formula or equation is the following."}, {"title": "Dalton\u2019s Law on Partial Pressure .txt", "text": "So we can represent the partial pressure of any gas in a mixture of gasses by the following equation."}, {"title": "Dalton\u2019s Law on Partial Pressure .txt", "text": "The partial pressure is equal to the mole fraction of that gas in our mixture times the total pressure."}, {"title": "Dalton\u2019s Law on Partial Pressure .txt", "text": "In other words, I want to represent this in this following way let's see what we do."}, {"title": "Dalton\u2019s Law on Partial Pressure .txt", "text": "P total is equal to well, how many blue molecules on the system?"}, {"title": "Dalton\u2019s Law on Partial Pressure .txt", "text": "Two."}, {"title": "Dalton\u2019s Law on Partial Pressure .txt", "text": "How many molecules altogether?"}, {"title": "Dalton\u2019s Law on Partial Pressure .txt", "text": "Five."}, {"title": "Dalton\u2019s Law on Partial Pressure .txt", "text": "So the mole fraction of my blue guy is two over five times my P total plus the partial pressure of my red molecules."}, {"title": "Dalton\u2019s Law on Partial Pressure .txt", "text": "We have three red molecules over five red molecules times the P total."}, {"title": "Dalton\u2019s Law on Partial Pressure .txt", "text": "So this is the partial pressure due to the blue molecules."}, {"title": "Dalton\u2019s Law on Partial Pressure .txt", "text": "These guys are the same plus the partial pressures into the red molecules."}, {"title": "Dalton\u2019s Law on Partial Pressure .txt", "text": "These guys are also the same."}, {"title": "Dalton\u2019s Law on Partial Pressure .txt", "text": "Gives us P total."}, {"title": "Dalton\u2019s Law on Partial Pressure .txt", "text": "And look, common denominator adds a two and three."}, {"title": "Dalton\u2019s Law on Partial Pressure .txt", "text": "I get five and five."}, {"title": "Dalton\u2019s Law on Partial Pressure .txt", "text": "The five cancel and I simply get P total equals P total."}, {"title": "Dalton\u2019s Law on Partial Pressure .txt", "text": "So this formula makes sense."}, {"title": "Dalton\u2019s Law on Partial Pressure .txt", "text": "And in fact, this formula is called a Dalton's Law of partial pressures."}, {"title": "Dalton\u2019s Law on Partial Pressure .txt", "text": "And this law can be derived using the ideal gas law."}, {"title": "Dalton\u2019s Law on Partial Pressure .txt", "text": "And let's see how."}, {"title": "Dalton\u2019s Law on Partial Pressure .txt", "text": "Well, suppose in part E, we have three types of gas molecules and each type has N number of moles."}, {"title": "Dalton\u2019s Law on Partial Pressure .txt", "text": "So n one, N two and n three."}, {"title": "Dalton\u2019s Law on Partial Pressure .txt", "text": "So red molecules, blue molecules and purple molecules."}, {"title": "Dalton\u2019s Law on Partial Pressure .txt", "text": "Well, what's the total number of molecules or moles in molecules of my system?"}, {"title": "Dalton\u2019s Law on Partial Pressure .txt", "text": "Well, in this case, it was two plus three."}, {"title": "Dalton\u2019s Law on Partial Pressure .txt", "text": "So we added them."}, {"title": "Dalton\u2019s Law on Partial Pressure .txt", "text": "So we do the same thing."}, {"title": "Dalton\u2019s Law on Partial Pressure .txt", "text": "We add the moles, add the number of molecules."}, {"title": "Dalton\u2019s Law on Partial Pressure .txt", "text": "The N total is n plus n one plus n two plus n three is my total."}, {"title": "Dalton\u2019s Law on Partial Pressure .txt", "text": "So, if I want to find the total pressure using the ideal gas law, the following has to be done."}, {"title": "Dalton\u2019s Law on Partial Pressure .txt", "text": "I rearrange it a bit and bring the D over on this side."}, {"title": "Dalton\u2019s Law on Partial Pressure .txt", "text": "And again, P total is equal to while my volume is constant, I'm assuming it's constant."}, {"title": "Dalton\u2019s Law on Partial Pressure .txt", "text": "My temperature is constant."}, {"title": "Dalton\u2019s Law on Partial Pressure .txt", "text": "Also, R is a gas constant."}, {"title": "Dalton\u2019s Law on Partial Pressure .txt", "text": "It's always constant."}, {"title": "Dalton\u2019s Law on Partial Pressure .txt", "text": "And now I plug in N total or the total number of molecules in my system."}, {"title": "Dalton\u2019s Law on Partial Pressure .txt", "text": "Now I can go to the next step."}, {"title": "Dalton\u2019s Law on Partial Pressure .txt", "text": "And instead of writing N total, I plug in all these three guides or the addition of these three guides and I get in parentheses n one plus n two plus n three times RT divided by V.\nAnd now I need simple algebra to distribute to each guide."}, {"title": "Dalton\u2019s Law on Partial Pressure .txt", "text": "And I get n one R T over V plus n two r T over V plus n three r T over V. And we see using the ideal gas law that we get the same exact thing as up here."}, {"title": "Dalton\u2019s Law on Partial Pressure .txt", "text": "So P total is equal to partial pressure of gas one plus partial pressure of gas two and plus partial pressure of gas three."}, {"title": "Dalton\u2019s Law on Partial Pressure .txt", "text": "So once again, we found this formula first using the kinetic theory."}, {"title": "Dalton\u2019s Law on Partial Pressure .txt", "text": "And then we confirm that in fact, this works using the ideal gas law."}, {"title": "Dalton\u2019s Law on Partial Pressure .txt", "text": "So this formula may makes a lot of sense."}, {"title": "Oxidation Numbers Example .txt", "text": "In this example, we're going to assign oxidation numbers to atoms of molecules."}, {"title": "Oxidation Numbers Example .txt", "text": "Here we have nine molecules."}, {"title": "Oxidation Numbers Example .txt", "text": "So let's begin."}, {"title": "Oxidation Numbers Example .txt", "text": "In this molecule, we have an N atom at an fatom."}, {"title": "Oxidation Numbers Example .txt", "text": "An fatom, according to our table, precedes or is more important than an N atom."}, {"title": "Oxidation Numbers Example .txt", "text": "And that means we first assign our number."}, {"title": "Oxidation Numbers Example .txt", "text": "Oxidation number to F gets negative one."}, {"title": "Oxidation Numbers Example .txt", "text": "But since we have three F's, that means this one has a negative three."}, {"title": "Oxidation Numbers Example .txt", "text": "And since our entire molecule is neutral, this one must be plus three."}, {"title": "Oxidation Numbers Example .txt", "text": "Plus three minus three gives you neutral."}, {"title": "Oxidation Numbers Example .txt", "text": "So zero charge makes sense."}, {"title": "Oxidation Numbers Example .txt", "text": "Let's look at Ammonium NH Four."}, {"title": "Oxidation Numbers Example .txt", "text": "NH four has an overall charge of plus one."}, {"title": "Oxidation Numbers Example .txt", "text": "Now let's look at the atoms."}, {"title": "Oxidation Numbers Example .txt", "text": "Our H atom is more important than N atom, so we assign to H first."}, {"title": "Oxidation Numbers Example .txt", "text": "Since H is not attached to a metal atom, we assign H a plus one."}, {"title": "Oxidation Numbers Example .txt", "text": "So four h is get plus four."}, {"title": "Oxidation Numbers Example .txt", "text": "Since we want a plus one overall charge, this guy must be a minus three."}, {"title": "Oxidation Numbers Example .txt", "text": "Minus three plus four gives you a plus one."}, {"title": "Oxidation Numbers Example .txt", "text": "Let's look at no three."}, {"title": "Oxidation Numbers Example .txt", "text": "This guy has negative three as an overall charge."}, {"title": "Oxidation Numbers Example .txt", "text": "So let's look at the individual atoms."}, {"title": "Oxidation Numbers Example .txt", "text": "All is more important than N. That means we first assign our oval, so all gets a negative two."}, {"title": "Oxidation Numbers Example .txt", "text": "Since we have a three zeros, this becomes negative six for three OS."}, {"title": "Oxidation Numbers Example .txt", "text": "And since we want a negative one overall, our N must be plus five."}, {"title": "Oxidation Numbers Example .txt", "text": "Notice how in our three examples, our N differed in every example."}, {"title": "Oxidation Numbers Example .txt", "text": "In this one, it was a plus three."}, {"title": "Oxidation Numbers Example .txt", "text": "In this one, there was a negative three, and this one was a plus five."}, {"title": "Oxidation Numbers Example .txt", "text": "Let's look at four."}, {"title": "Oxidation Numbers Example .txt", "text": "In four we have an ionic compound, and that means we have an atom and another molecule."}, {"title": "Oxidation Numbers Example .txt", "text": "So this atom, since it's in the second group, gets a plus two."}, {"title": "Oxidation Numbers Example .txt", "text": "So this is a plus two."}, {"title": "Oxidation Numbers Example .txt", "text": "And we see from this example that each individual guy gets a minus one."}, {"title": "Oxidation Numbers Example .txt", "text": "So minus one times two gives us a plus two for this whole guy."}, {"title": "Oxidation Numbers Example .txt", "text": "Another way of seeing it a minus two, sorry."}, {"title": "Oxidation Numbers Example .txt", "text": "Another way of seeing it would have been to realize that this whole compound that is neutral."}, {"title": "Oxidation Numbers Example .txt", "text": "So if this is plus two, this must be minus two."}, {"title": "Oxidation Numbers Example .txt", "text": "Now, the individual atoms are the same as this example."}, {"title": "Oxidation Numbers Example .txt", "text": "Let's look at this guy."}, {"title": "Oxidation Numbers Example .txt", "text": "Well, from this example, we know that each ammonia molecule has a plus one charge."}, {"title": "Oxidation Numbers Example .txt", "text": "That means two ammonia molecules will have a plus two charge."}, {"title": "Oxidation Numbers Example .txt", "text": "Now, since this entire compound is neutral, that means this guy has to be a minus two."}, {"title": "Oxidation Numbers Example .txt", "text": "And now let's assign individual oxation numbers to each atom."}, {"title": "Oxidation Numbers Example .txt", "text": "So o perceives s that means we assign to o first."}, {"title": "Oxidation Numbers Example .txt", "text": "O gets a negative two."}, {"title": "Oxidation Numbers Example .txt", "text": "So negative two times four atoms gives you a negative eight for O."}, {"title": "Oxidation Numbers Example .txt", "text": "And since we want an overall negative two on this molecule, this S must have a plus six."}, {"title": "Oxidation Numbers Example .txt", "text": "Plus six minus eight gives you a negative two."}, {"title": "Oxidation Numbers Example .txt", "text": "Now, we're not going to assign anything to this guy because we already did that in example, too."}, {"title": "Oxidation Numbers Example .txt", "text": "Let's look at six."}, {"title": "Oxidation Numbers Example .txt", "text": "B a."}, {"title": "Oxidation Numbers Example .txt", "text": "So four."}, {"title": "Oxidation Numbers Example .txt", "text": "So, once again, BA BA, since it's in a second group, must have a plus two."}, {"title": "Oxidation Numbers Example .txt", "text": "So BA gets a plus two."}, {"title": "Oxidation Numbers Example .txt", "text": "Let's look at so four."}, {"title": "Oxidation Numbers Example .txt", "text": "Now, so four from this example, we know has a negative two."}, {"title": "Oxidation Numbers Example .txt", "text": "So this guy must be negative two."}, {"title": "Oxidation Numbers Example .txt", "text": "Another way of seeing it would have been to realize that this whole thing is neutral."}, {"title": "Oxidation Numbers Example .txt", "text": "So if this is plus two, this might be minus two."}, {"title": "Oxidation Numbers Example .txt", "text": "Now, we're not going to assign anything to individual atoms, because we did that in this example."}, {"title": "Oxidation Numbers Example .txt", "text": "Let's look at seven."}, {"title": "Oxidation Numbers Example .txt", "text": "Now, in seven, we have copper and S, right?"}, {"title": "Oxidation Numbers Example .txt", "text": "S precedes copper."}, {"title": "Oxidation Numbers Example .txt", "text": "So S is in the same group as oxygen."}, {"title": "Oxidation Numbers Example .txt", "text": "So S must have a minus two."}, {"title": "Oxidation Numbers Example .txt", "text": "So S as a minus two."}, {"title": "Oxidation Numbers Example .txt", "text": "Now, this whole compound has a neutral charge."}, {"title": "Oxidation Numbers Example .txt", "text": "So if this is minus two, our copper must be plus one each, right?"}, {"title": "Oxidation Numbers Example .txt", "text": "So this makes our two coppers plus two."}, {"title": "Oxidation Numbers Example .txt", "text": "Let's look at this guy."}, {"title": "Oxidation Numbers Example .txt", "text": "Now, we already did ammonia."}, {"title": "Oxidation Numbers Example .txt", "text": "We know that's."}, {"title": "Oxidation Numbers Example .txt", "text": "Plus one."}, {"title": "Oxidation Numbers Example .txt", "text": "So this whole thing is plus one."}, {"title": "Oxidation Numbers Example .txt", "text": "That means this whole guy must be plus one."}, {"title": "Oxidation Numbers Example .txt", "text": "Now this whole guy must be minus one."}, {"title": "Oxidation Numbers Example .txt", "text": "And we saw that in this example, it was minus one."}, {"title": "Oxidation Numbers Example .txt", "text": "So this whole guy is minus one."}, {"title": "Oxidation Numbers Example .txt", "text": "Now let's look at individual atoms."}, {"title": "Oxidation Numbers Example .txt", "text": "Individual atoms are the same exact as these two guys."}, {"title": "Oxidation Numbers Example .txt", "text": "This must be negative two times three, negative six."}, {"title": "Oxidation Numbers Example .txt", "text": "For three oxygen molecules to create a negative one."}, {"title": "Oxidation Numbers Example .txt", "text": "Overall, on this molecule, this N must be a plus five."}, {"title": "Oxidation Numbers Example .txt", "text": "Plus five, minus six, negative one."}, {"title": "Oxidation Numbers Example .txt", "text": "You can check that."}, {"title": "Oxidation Numbers Example .txt", "text": "And it works for Ammonium, the same thing that we did here."}, {"title": "Oxidation Numbers Example .txt", "text": "This H is assigned first, so it gets a plus one times four, a plus four."}, {"title": "Oxidation Numbers Example .txt", "text": "So this guy gets a plus four."}, {"title": "Oxidation Numbers Example .txt", "text": "And this end, to create a plus one or charge, must be negative three."}, {"title": "Oxidation Numbers Example .txt", "text": "So negative three plus four gives you positive one works."}, {"title": "Oxidation Numbers Example .txt", "text": "Let's look at the last one, this guy."}, {"title": "Oxidation Numbers Example .txt", "text": "Well, we already know from this example, in this example that so four is negative two."}, {"title": "Oxidation Numbers Example .txt", "text": "So four must be negative two."}, {"title": "Oxidation Numbers Example .txt", "text": "So our Zn must be plus two because we want a mutual atom."}, {"title": "Oxidation Numbers Example .txt", "text": "Now let's look at individual guys."}, {"title": "Oxidation Numbers Example .txt", "text": "Well, it's the same thing as we did here."}, {"title": "Oxidation Numbers Example .txt", "text": "This guy assigned first to oxygen."}, {"title": "Oxidation Numbers Example .txt", "text": "So oxygen gets a negative two, times four, negative eight."}, {"title": "Oxidation Numbers Example .txt", "text": "And we want an overall of negative two."}, {"title": "Oxidation Numbers Example .txt", "text": "That means our S must get a plus six."}, {"title": "Oxidation Numbers Example .txt", "text": "Plus six minus eight gives us a negative two."}, {"title": "Cell diagram .txt", "text": "Electrochemical cells can be represented using something called a cell diagram or an electrochemical cell diagram."}, {"title": "Cell diagram .txt", "text": "Now, this is simply a simplification of this drawing here, and it looks like this."}, {"title": "Cell diagram .txt", "text": "So let's examine our full drawing."}, {"title": "Cell diagram .txt", "text": "So within our anode, there's an oxidation reaction."}, {"title": "Cell diagram .txt", "text": "So copper solid is oxidized into aqueous copper and it releases electrons."}, {"title": "Cell diagram .txt", "text": "Electrons travel in this conductor to this metal bar, the cadmium."}, {"title": "Cell diagram .txt", "text": "The cadmium solid."}, {"title": "Cell diagram .txt", "text": "And then the electrons react with our aqueous cadmium, forming our solid cadmium."}, {"title": "Cell diagram .txt", "text": "So reduction occurs in the cathode and oxidation occurs in the anode."}, {"title": "Cell diagram .txt", "text": "Now, this diagram is very tedious to draw."}, {"title": "Cell diagram .txt", "text": "We can represent this diagram in a simple way using a cell diagram seen on this side."}, {"title": "Cell diagram .txt", "text": "So these guys are equivalent representations."}, {"title": "Cell diagram .txt", "text": "Now, the double bar in the middle of the vertical double bar represents our sold bridge."}, {"title": "Cell diagram .txt", "text": "The single vertical lines represents our separation of phases."}, {"title": "Cell diagram .txt", "text": "For example, we have our solid copper and our aqueous copper."}, {"title": "Cell diagram .txt", "text": "So acreage copper sound and solution and beaker one."}, {"title": "Cell diagram .txt", "text": "And the solid copper is this electrode bar, the same way that we have the electrode bar this side and acreage copper on this side."}, {"title": "Cell diagram .txt", "text": "And this is our separation of phases."}, {"title": "Cell diagram .txt", "text": "The same concept on this side."}, {"title": "Cell diagram .txt", "text": "This cadmium bar is separated by phases in the solution."}, {"title": "Cell diagram .txt", "text": "So we have the ions here and the solid cadmium in the bar the same way that this bar here, this vertical line represents these two phases."}, {"title": "Cell diagram .txt", "text": "Now, this is their anode and this is their cathode."}, {"title": "Cell diagram .txt", "text": "So the thing on your left is always the anode."}, {"title": "Cell diagram .txt", "text": "The thing on your right is always the cathode."}, {"title": "Cell diagram .txt", "text": "And electrons travel from this guy to this guy."}, {"title": "Cell diagram .txt", "text": "So the way you read this is that copper solid oxidize releasing two electrons and this ion."}, {"title": "Cell diagram .txt", "text": "Now, these two electrons travel to this side into the cathode."}, {"title": "Cell diagram .txt", "text": "And in the cathode, they react with the cadmium, forming our cadmium solid."}, {"title": "Cell diagram .txt", "text": "And this is how you read the cell diagram for any electrochemical cell."}, {"title": "Half equivalence point .txt", "text": "In this lecture, we're going to talk about Titrating, an asset using a base."}, {"title": "Half equivalence point .txt", "text": "Now, if you don't know what Titration is and you don't know what an equivalence point Is, then check out the link below."}, {"title": "Half equivalence point .txt", "text": "So, once again, we're tightrading an acid with the base."}, {"title": "Half equivalence point .txt", "text": "And here's our Titration curve where the y axis is PH and the x axis is the volume of base added."}, {"title": "Half equivalence point .txt", "text": "Now, we've defined the equivalence point to be the point at which all the acid has been neutralized."}, {"title": "Half equivalence point .txt", "text": "So every single molecule of acid in our buffer system has been neutralized."}, {"title": "Half equivalence point .txt", "text": "Now, we can also define something called the half equivalence point."}, {"title": "Half equivalence point .txt", "text": "And the half equivalence point is the point at which exactly half of the acid in our buffer system has been neutralized."}, {"title": "Half equivalence point .txt", "text": "Now, suppose we choose our buffer system to consist of acetic acid."}, {"title": "Half equivalence point .txt", "text": "Now, acetic acid associates it to acetate ion and an H plus ion."}, {"title": "Half equivalence point .txt", "text": "Now, suppose we begin adding some volume of our base."}, {"title": "Half equivalence point .txt", "text": "And suppose we choose our base to be ammonia."}, {"title": "Half equivalence point .txt", "text": "So we're adding the volume of ammonia into our acetic acid."}, {"title": "Half equivalence point .txt", "text": "Now, the reaction looks like this."}, {"title": "Half equivalence point .txt", "text": "The conjugate acid, acetic acid dissociates into the conjugate base acetate ion."}, {"title": "Half equivalence point .txt", "text": "This base, the ammonia gains an H becoming ammonia."}, {"title": "Half equivalence point .txt", "text": "Now, so, let's look at this definition again."}, {"title": "Half equivalence point .txt", "text": "The half equivalence point is the point at which exactly half of the assets, exactly half of this guy has dissociated into this guy Aka."}, {"title": "Half equivalence point .txt", "text": "Has been neutralized."}, {"title": "Half equivalence point .txt", "text": "So that means we can define the half equivalence point in another way."}, {"title": "Half equivalence point .txt", "text": "The half equivalence point is the point at which the concentration of the conjugate acid equals the concentration of the conjugate base."}, {"title": "Half equivalence point .txt", "text": "Because half of this is now this."}, {"title": "Half equivalence point .txt", "text": "So the concentration of this guy equals this guy."}, {"title": "Half equivalence point .txt", "text": "Well, why is this definition important?"}, {"title": "Half equivalence point .txt", "text": "Well, we'll see why in a second."}, {"title": "Half equivalence point .txt", "text": "Let's look at the Henderson Hasselblack formula or equation."}, {"title": "Half equivalence point .txt", "text": "Now, if you don't know what this formula is, check out the link above."}, {"title": "Half equivalence point .txt", "text": "So, this equation states that PH is equal to PKA of our acid plus log of this ratio the concentration of the conjugate base over the concentration of the conjugate acid."}, {"title": "Half equivalence point .txt", "text": "And this PH is the PH of our buffer system."}, {"title": "Half equivalence point .txt", "text": "So notice that since this guy equals this guy, this divided by this is one."}, {"title": "Half equivalence point .txt", "text": "So what's inside here is simply one."}, {"title": "Half equivalence point .txt", "text": "So let's rewrite it."}, {"title": "Half equivalence point .txt", "text": "PH is equal to PKA plus log of one."}, {"title": "Half equivalence point .txt", "text": "But what's log of one?"}, {"title": "Half equivalence point .txt", "text": "Well, log of one is zero."}, {"title": "Half equivalence point .txt", "text": "And that means PH equals PKA."}, {"title": "Half equivalence point .txt", "text": "Well, that's nice and all, but why is that important?"}, {"title": "Half equivalence point .txt", "text": "Where's the significance?"}, {"title": "Half equivalence point .txt", "text": "Well, this means that now we can choose the PH of our bumper system by simply choosing an acid with PKA that's closest to our desired PH."}, {"title": "Half equivalence point .txt", "text": "So suppose, for example, I want my bubble system to have a PH of 4.7."}, {"title": "Half equivalence point .txt", "text": "Now, how I find the asset to use is I simply find the acid with the PKA value closest to 4.7."}, {"title": "Half equivalence point .txt", "text": "Now, I go online I find my table, I look up an acid with a PH that's a PKA closest to a PH of 4.7, and I find that it's acetic acid."}, {"title": "Half equivalence point .txt", "text": "So now I know, using this equation here, that if I choose my buffer sydney system to consist of acetic acetic acid, my PH of my bumper system will be 4.7."}, {"title": "Half equivalence point .txt", "text": "And that's important."}, {"title": "Parts per million Example .txt", "text": "Parts per million is a way of finding the concentration of the solution."}, {"title": "Parts per million Example .txt", "text": "It's represented by the letters Ppm or parts per million."}, {"title": "Parts per million Example .txt", "text": "The formula is mass of compound x divided by total mass of solution multiplied by ten to the six or million."}, {"title": "Parts per million Example .txt", "text": "Now, since this is a ratio that units cancel and Ppm is unitless, so now it's still an example using parts per million."}, {"title": "Parts per million Example .txt", "text": "In this example, we start with 25 bowls of water in a cup."}, {"title": "Parts per million Example .txt", "text": "Here's our cup."}, {"title": "Parts per million Example .txt", "text": "The blue dots are the water molecules, nothing else exists."}, {"title": "Parts per million Example .txt", "text": "You want to find them out in grams of HCL to add to create a 90,000 parts per million solution."}, {"title": "Parts per million Example .txt", "text": "So you want to go from this cup to this cup, where this cup contains HCL molecules in the concentration of 90,000 parts per million."}, {"title": "Parts per million Example .txt", "text": "We want to find the amount of grams of the red dots we need to add to create such a solution."}, {"title": "Parts per million Example .txt", "text": "The first step is to calculate the molecular weight of water."}, {"title": "Parts per million Example .txt", "text": "To calculate the molecular weight of water, we simply add the atomic weight of oxygen plus two times the atomic weight of H because we have a substrate of two, so we get 16 grams/mol of oxygen plus two times 1 gram/mol of H gives us 18 grams/mol."}, {"title": "Parts per million Example .txt", "text": "So the molecular weight of water is 18 grams/mol."}, {"title": "Parts per million Example .txt", "text": "Now, to find the amount in grams of water that we have in our initial solution, we need to multiply the molecular weight by the 25 moles of H 20 that we have."}, {"title": "Parts per million Example .txt", "text": "So 18 grams/mol times 25 moles gives you 450."}, {"title": "Parts per million Example .txt", "text": "Now, moles cancel, the grams are left, so we have 450 grams of H 20."}, {"title": "Parts per million Example .txt", "text": "Now, we want to find the amount of HCL we need to add in terms of grams to create a 90,000 parts per million solution."}, {"title": "Parts per million Example .txt", "text": "So we simply use the parts per million formula."}, {"title": "Parts per million Example .txt", "text": "We say, well, we want to create a 90,000 grams or parts per million solution equals x is the amount of HCL grams we need to add divided by the total amount of grounds we have the solution."}, {"title": "Parts per million Example .txt", "text": "So we already have 450 grams of water plus the amount of HCL and grounds we will add."}, {"title": "Parts per million Example .txt", "text": "So plus x times ten to the 6th or 1 million."}, {"title": "Parts per million Example .txt", "text": "We do a little bit of simple algebra to solve for x, we divide through by ten to the six we get 90,000 divided by 1 million equals this guy."}, {"title": "Parts per million Example .txt", "text": "Now, we multiply through by 450 plus x and we get 0.9, which is simply this guy times 450 plus x equals the x was left over on that side, so equals x."}, {"title": "Parts per million Example .txt", "text": "We saw for x you get x equals 44.51 grams of HCL."}, {"title": "Parts per million Example .txt", "text": "So we want to add 44 grams, 44.51\ngrams of HCL to our initial 450 grams of water to to create a 90,000 parts per million solution of HCL."}, {"title": "Solubility Product Constant .txt", "text": "In this lecture, we're going to talk about the solubility of powder constant, KSP."}, {"title": "Solubility Product Constant .txt", "text": "Before we talk about KSP, let's talk about the solubility of ionic compounds."}, {"title": "Solubility Product Constant .txt", "text": "Now, all ionic compounds have the ability to dissociate into their ion form when added into water."}, {"title": "Solubility Product Constant .txt", "text": "For example, let's take ionic compound sodium chloride."}, {"title": "Solubility Product Constant .txt", "text": "When we add sodium chloride chloride into water, it dissociates into two ions, sodium and chloride."}, {"title": "Solubility Product Constant .txt", "text": "Now, this reaction is called the forward reaction or dissolution."}, {"title": "Solubility Product Constant .txt", "text": "The reverse reaction is just as likely to occur, and that's called precipitation, the sufformation of ionic compound from its ion form."}, {"title": "Solubility Product Constant .txt", "text": "Now, initially, when we add photos chloride into water, the forward rate is much higher than the reverse rate."}, {"title": "Solubility Product Constant .txt", "text": "Eventually, however, though dynamic equilibrium is achieved, at this point, the forward rate is equal to the reverse rate."}, {"title": "Solubility Product Constant .txt", "text": "And at this point, the solution is said to be saturated, which basically means that the concentration of the ions or dissolved ions is that it's maximum."}, {"title": "Solubility Product Constant .txt", "text": "So these guys are at the maximum."}, {"title": "Solubility Product Constant .txt", "text": "Now, whenever we talk about normal equations or normal reactions, not fluidation reactions, we talk about equilibrium constants."}, {"title": "Solubility Product Constant .txt", "text": "In the same way, when we talk about salvation reactions, we could talk about something called solubility product constant or KST."}, {"title": "Solubility Product Constant .txt", "text": "Now, when we determine the normal equilibrium constant, we don't include solids and liquids in our calculation."}, {"title": "Solubility Product Constant .txt", "text": "And in the same way, when we talk about salvation or solubility product constant KFC, we don't include solids and liquids."}, {"title": "Solubility Product Constant .txt", "text": "For example, let's take a reaction of solid Orion compound AB that associates in water into A plus B."}, {"title": "Solubility Product Constant .txt", "text": "Now, since we don't count the solids, we don't count the liquids, but we do count gases and Aqueous compounds."}, {"title": "Solubility Product Constant .txt", "text": "When we determine the KSP or the solubility of bonus constants, we don't count this guy or the other guy."}, {"title": "Solubility Product Constant .txt", "text": "We only count these two guys."}, {"title": "Solubility Product Constant .txt", "text": "So KSP is equal to the concentration of A times the concentration of B."}, {"title": "Solubility Product Constant .txt", "text": "In this problem, we're given some unknown amount of barium sulfate and some unknown amount of water in a cup."}, {"title": "Solubility Product Constant .txt", "text": "Now, we want to mix the two and wait for dynamic equilibrium to establish."}, {"title": "Solubility Product Constant .txt", "text": "Once equilibrium establishes, we're given that the KSP or the Solubility product is equal to 1.0 times ten to negative ten at 25 degrees Celsius."}, {"title": "Solubility Product Constant .txt", "text": "So we want to find the solubility of barium sulfate."}, {"title": "Solubility Product Constant .txt", "text": "To find the solubility of barium sulfate, we must first write the dissociation reaction for barium sulfate."}, {"title": "Solubility Product Constant .txt", "text": "Therefore, we get 1 mol of barium sulfate in its solid form, dissociates into 1 mol of barium plus 1 mol of sulfate, and both guys are in the Aqueous form."}, {"title": "Solubility Product Constant .txt", "text": "The first step is to write the KSP equation."}, {"title": "Solubility Product Constant .txt", "text": "To write the KSP equation, we simply realize that this guy is a solid and therefore he doesn't count."}, {"title": "Solubility Product Constant .txt", "text": "In this equation."}, {"title": "Solubility Product Constant .txt", "text": "These guys only count because they're both atreus."}, {"title": "Solubility Product Constant .txt", "text": "Remember, we never count solids and we never count liquids."}, {"title": "Solubility Product Constant .txt", "text": "Therefore, KSP is equal to the concentration of barium times the concentration of sulfate ion."}, {"title": "Solubility Product Constant .txt", "text": "Finally, since this guy is 1.0 times cents and negative ten, we say KSP is equal to 1.0 times ten to negative ten equals."}, {"title": "Solubility Product Constant .txt", "text": "Now, since this is X and this is X, you write X is here."}, {"title": "Solubility Product Constant .txt", "text": "Now, since barium there's 1 mol of barrium, we put a one in front of the X for barium."}, {"title": "Solubility Product Constant .txt", "text": "And since there's a 1 mol of sulfate, we put the 1 mol in front of the X."}, {"title": "Solubility Product Constant .txt", "text": "So we get one X times one X equals X squared."}, {"title": "Solubility Product Constant .txt", "text": "Finally, we use a little bit of algebra."}, {"title": "Solubility Product Constant .txt", "text": "We pick the radical, and we get x equals one times cents to negative five molar."}, {"title": "Solubility Product Constant .txt", "text": "That is the solubility of barium sulfate in water at 25 Celsius is one times cents to negative ten molar or moles per volume."}, {"title": "Catalysts .txt", "text": "So earlier in another lecture, we spoke about the relationship between temperature and reaction rate."}, {"title": "Catalysts .txt", "text": "And we said that as we increase our temperature, our reaction rate also increases because on average, more molecules will have enough kinetic energy to overcome the activation energy."}, {"title": "Catalysts .txt", "text": "Now, today we're going to look at something called catalysts."}, {"title": "Catalysts .txt", "text": "Now, catalysts are organic or inorganic molecules that also, like temperature, affect our rate of reaction."}, {"title": "Catalysts .txt", "text": "Now, let's look at the following hypothetical example in which reactants A plus B react to form a product AB."}, {"title": "Catalysts .txt", "text": "Now, let's suppose that our reaction is reversible, meaning it goes forward and backward."}, {"title": "Catalysts .txt", "text": "And that means an equilibrium."}, {"title": "Catalysts .txt", "text": "Our rate forward will be the same as the rate backwards."}, {"title": "Catalysts .txt", "text": "Now let's look at the catalyzed reaction."}, {"title": "Catalysts .txt", "text": "Suppose we add a catalyst, catalyst C, to our reactants."}, {"title": "Catalysts .txt", "text": "Now, before we look at the mechanism by which it increases the rate, let's make sure we understand the fact that catalysts are not used up in reaction."}, {"title": "Catalysts .txt", "text": "In other words, if you add some catalyst to our reactants, you will get that same catalyst back at the end of your reaction."}, {"title": "Catalysts .txt", "text": "Now, that catalyst might react somehow with one of the reactants, maybe covalently or non covalent."}, {"title": "Catalysts .txt", "text": "In other words, it might buy to it and help them for the products."}, {"title": "Catalysts .txt", "text": "But at the end it will separate and you will be able to get your feed back."}, {"title": "Catalysts .txt", "text": "All right?"}, {"title": "Catalysts .txt", "text": "So let's look at the mechanism by which these catalysts affect our reaction rates."}, {"title": "Catalysts .txt", "text": "So, in order to see this, we have to go back to our Iranians equation."}, {"title": "Catalysts .txt", "text": "This equation we spoke about when we spoke about temperature and reaction rate."}, {"title": "Catalysts .txt", "text": "So K, our reaction constant is equal to z times p. Now, z and p are the scarcity factor and the frequency of collisions."}, {"title": "Catalysts .txt", "text": "Now, this guy e is what our catalyst affects."}, {"title": "Catalysts .txt", "text": "Now, catalysts speed up reactions by lowering the activation energy needed to convert the reactants to products."}, {"title": "Catalysts .txt", "text": "Now, this in turn increases the number of molecules that have enough kinetic energy to climb that activation barrier."}, {"title": "Catalysts .txt", "text": "In other words, it decreases this activation energy EA, thereby increasing this e component."}, {"title": "Catalysts .txt", "text": "And this in turn increases our rate constant, which is directly proportional to rate of reaction."}, {"title": "Catalysts .txt", "text": "And that's how the rates of reactions are increased by catabalists."}, {"title": "Catalysts .txt", "text": "Now, let's look at this graph."}, {"title": "Catalysts .txt", "text": "It's energy in the Y axis versus time or progress or reaction on the x axis."}, {"title": "Catalysts .txt", "text": "Now, this black curve is the curve that represents before additional catalysts."}, {"title": "Catalysts .txt", "text": "Notice activation energy goes all the way up to this blue level."}, {"title": "Catalysts .txt", "text": "Now, when you add that catalyst, what happens is that activation energy is lowered by this much to this red level."}, {"title": "Catalysts .txt", "text": "And that means more molecules, on average will have enough kinetic energy to climb this new activation barrier and form the product."}, {"title": "Catalysts .txt", "text": "And that's exactly what happens when you add a catalyst."}, {"title": "Catalysts .txt", "text": "Now, it's very important to understand the following point."}, {"title": "Catalysts .txt", "text": "Catalysts do not, and I repeat, do not affect the equilibrium of reaction."}, {"title": "Catalysts .txt", "text": "In other words, what catalysts do is they speed up their forward reaction and reverse reaction."}, {"title": "Catalysts .txt", "text": "But the final concentrations of our product and reactions remain the same."}, {"title": "Catalysts .txt", "text": "In other words, let's look at this uncannyze and catalyze reaction."}, {"title": "Catalysts .txt", "text": "Again, suppose that the concentration and equilibrium of our uncatalyzed are as following we have concentration of A, we have concentration of B and construction of our product AB."}, {"title": "Catalysts .txt", "text": "Now, for the catalyzed reaction, even though equilibrium will be reached much quicker because of a catalyst, the final concentrations are exactly the same."}, {"title": "Catalysts .txt", "text": "They have not changed."}, {"title": "Catalysts .txt", "text": "In other words, catalysts do not touch the equilibrium of our reaction."}, {"title": "Catalysts .txt", "text": "They affect the kinetics of our reaction, but they do not affect equilibrium."}, {"title": "Catalysts .txt", "text": "Now, we're going to examine the two types of catalysts."}, {"title": "Catalysts .txt", "text": "So we have heterogeneous catalysts are molecules that are in a different state compared to the reactants."}, {"title": "Catalysts .txt", "text": "In other words, if our reactants are in a gas state or liquid state then our catalysts are in a solid state."}, {"title": "Catalysts .txt", "text": "Now, when we're dealing with heterogeneous catalysts, namely Salad catalysts, this is what happens."}, {"title": "Catalysts .txt", "text": "Our reactants absorb momentarily or bind to the catalyst which weaken the bonds, decreasing activation energy which in turn increases the reaction rate."}, {"title": "Catalysts .txt", "text": "So let's look at the following uncategorized reaction."}, {"title": "Catalysts .txt", "text": "BR two reacts with C two h four to produce C two H two BR two."}, {"title": "Catalysts .txt", "text": "Now, this by itself is a very slow occurring reaction."}, {"title": "Catalysts .txt", "text": "But if you add a catalyst, a metal catalyst, this reaction will speed up."}, {"title": "Catalysts .txt", "text": "Let's look at the following illustration."}, {"title": "Catalysts .txt", "text": "So this is our metal catalyst."}, {"title": "Catalysts .txt", "text": "What happens is this reaction momentarily binds to the surface of our catalyst and this weakens the double bond."}, {"title": "Catalysts .txt", "text": "And then this other reactant can come from the top, attacking these carbons, thereby creating our product."}, {"title": "Catalysts .txt", "text": "Now, this is how metal catalysts act."}, {"title": "Catalysts .txt", "text": "An example of such a metal catalyst is, for example, fuel cells."}, {"title": "Catalysts .txt", "text": "In fuel cells, plant and catalyst acts in the same manner to speed up the reactions the oxidation and reduction reactions in an anode in a cathode."}, {"title": "Catalysts .txt", "text": "Now, if you want to learn more about fuel cells, check out the link above."}, {"title": "Catalysts .txt", "text": "So now let's look at homogeneous catalysts."}, {"title": "Catalysts .txt", "text": "Now, homogeneous catalysts are catalysts that are in the same state as our reactant, usually liquid or gas."}, {"title": "Catalysts .txt", "text": "A great and common example of a homogeneous catalyst are acids."}, {"title": "Catalysts .txt", "text": "Now, these guys weaken bonds by adding an H plus ion to one of the reactants, thereby lowering the activation energy and speeding up our reaction."}, {"title": "Catalysts .txt", "text": "For example, let's look at the following reaction."}, {"title": "Catalysts .txt", "text": "Now, this actually involves a bit of organic chemistry but bear with me and I'll try to explain it."}, {"title": "Catalysts .txt", "text": "What happens is one of the H molecules, one of the H ions is added to this age group, to this oxygen group and this weakens this bond here."}, {"title": "Catalysts .txt", "text": "So then the hydroxide form act as a base or a nucleophile attacking this carbon bond, thereby displacing this weaker bond."}, {"title": "Catalysts .txt", "text": "And it was weakened by the h group, remember?"}, {"title": "Catalysts .txt", "text": "So displacing."}, {"title": "Catalysts .txt", "text": "It forming our product."}, {"title": "Catalysts .txt", "text": "Now we have the oh group instead of the Och three group."}, {"title": "Catalysts .txt", "text": "And this is exactly how homogeneous catalysts act."}, {"title": "Catalysts .txt", "text": "In other words, they momentarily bind with our reactants, help them out, and then at the end, after a reaction is finished, they've move away, and you can isolate the catalyst at the end of your reaction."}, {"title": "Catalysts .txt", "text": "Now, a great example of biological catalysts are enzymes."}, {"title": "Catalysts .txt", "text": "Enzymes are usually proteins found in our body that speed up the rates of reactions or slow down the rates of reactions."}, {"title": "Heisenberg\u2019s Uncertainty Principle .txt", "text": "Now, in this lecture, I want to talk about a very interesting concept called the Heisenberg Uncertainty Principle."}, {"title": "Heisenberg\u2019s Uncertainty Principle .txt", "text": "Now, this principle comes from quantum mechanics and two experiments in quantum mechanics help define this principle."}, {"title": "Heisenberg\u2019s Uncertainty Principle .txt", "text": "The first experiment, which we'll talk about in great detail in another lecture was called a photoelectric experiment or simply the Photo Electric effect."}, {"title": "Heisenberg\u2019s Uncertainty Principle .txt", "text": "And this experiment was conducted by Einstein."}, {"title": "Heisenberg\u2019s Uncertainty Principle .txt", "text": "And what Einstein showed was that light, an electromagnetic phenomenon, had both particle like properties as well as wavelike properties."}, {"title": "Heisenberg\u2019s Uncertainty Principle .txt", "text": "In other words, light has the following property called wave particle duality."}, {"title": "Heisenberg\u2019s Uncertainty Principle .txt", "text": "And what this property shows or tells us is that whenever it's convenient, light can act as a wave."}, {"title": "Heisenberg\u2019s Uncertainty Principle .txt", "text": "And whenever it's convenient, light will act as a particle."}, {"title": "Heisenberg\u2019s Uncertainty Principle .txt", "text": "Now, following this experiment, another experiment was conducted known as the BROGLEY Experiment."}, {"title": "Heisenberg\u2019s Uncertainty Principle .txt", "text": "And what that experiment showed was that not only light has its property but other subatomic particles, like electrons also have this duality property or the wave particle duality property."}, {"title": "Heisenberg\u2019s Uncertainty Principle .txt", "text": "Now, these two experiments led directly to the following result the Uncertainty Principle, or the Heisenberg Uncertainty Principle, named after the guy who came up with the principle, Heisenberg."}, {"title": "Heisenberg\u2019s Uncertainty Principle .txt", "text": "Now, what this principle showed was that it showed that as you move downward in size from something large to the subatomic level the less your objects act like particles and the more they act as a wave."}, {"title": "Heisenberg\u2019s Uncertainty Principle .txt", "text": "In other words, if you get down to the subatomic level to the electrons and protons and neutrons the less your objects act as solid spheres and the more your objects act as waves."}, {"title": "Heisenberg\u2019s Uncertainty Principle .txt", "text": "Now, to demonstrate what this uncertainty principle states, I'll use the following example."}, {"title": "Heisenberg\u2019s Uncertainty Principle .txt", "text": "Suppose I have this relatively large ball which, from where you're sitting you can probably tell where the ball is and you can tell if the ball isn't moving so you could tell its velocity."}, {"title": "Heisenberg\u2019s Uncertainty Principle .txt", "text": "Now, suppose I go smaller."}, {"title": "Heisenberg\u2019s Uncertainty Principle .txt", "text": "Suppose I hold up this ball."}, {"title": "Heisenberg\u2019s Uncertainty Principle .txt", "text": "Now, once again, this is a relatively large ball."}, {"title": "Heisenberg\u2019s Uncertainty Principle .txt", "text": "And from where you're sitting, you could probably tell that the ball isn't moving and you could tell where the ball is."}, {"title": "Heisenberg\u2019s Uncertainty Principle .txt", "text": "Now, suppose I go even smaller."}, {"title": "Heisenberg\u2019s Uncertainty Principle .txt", "text": "Suppose I go down to this really tiny marble which you probably can't see from where you're sitting."}, {"title": "Heisenberg\u2019s Uncertainty Principle .txt", "text": "But I'll move it closer."}, {"title": "Heisenberg\u2019s Uncertainty Principle .txt", "text": "There's my particle."}, {"title": "Heisenberg\u2019s Uncertainty Principle .txt", "text": "There's my solid sphere."}, {"title": "Heisenberg\u2019s Uncertainty Principle .txt", "text": "Now, now that you saw the sphere, you could probably see that."}, {"title": "Heisenberg\u2019s Uncertainty Principle .txt", "text": "You could probably see it from where you're sitting."}, {"title": "Heisenberg\u2019s Uncertainty Principle .txt", "text": "But suppose now, I walk a mile away or a kilometer away and suppose I hold this ball."}, {"title": "Heisenberg\u2019s Uncertainty Principle .txt", "text": "Now, now, this ball becomes a spec."}, {"title": "Heisenberg\u2019s Uncertainty Principle .txt", "text": "You could still see it, but it's much, much smaller."}, {"title": "Heisenberg\u2019s Uncertainty Principle .txt", "text": "Now, suppose I walk a mile away and I hold this ball up."}, {"title": "Heisenberg\u2019s Uncertainty Principle .txt", "text": "Now, this ball you probably won't see really."}, {"title": "Heisenberg\u2019s Uncertainty Principle .txt", "text": "Well, you might see it if you have really good vision."}, {"title": "Heisenberg\u2019s Uncertainty Principle .txt", "text": "But I don't think I'll see it a mile away."}, {"title": "Heisenberg\u2019s Uncertainty Principle .txt", "text": "Now, suppose I hold this really tiny marble, the solid sphere, from a mile away you definitely won't see this one."}, {"title": "Heisenberg\u2019s Uncertainty Principle .txt", "text": "So in other words, the smaller you go, the less you see its position and the less you see its velocity."}, {"title": "Heisenberg\u2019s Uncertainty Principle .txt", "text": "If I walk 5 miles away and I hold either of these balls, you won't see any ball and you won't be able to tell where the ball is and with what speed or with what velocity it's moving."}, {"title": "Heisenberg\u2019s Uncertainty Principle .txt", "text": "The point is, and what this uncertainty principles show, is that as you shrink down to the atom and then to the sub atom, to the electron, you no longer are dealing with solid spheres."}, {"title": "Heisenberg\u2019s Uncertainty Principle .txt", "text": "They're no longer solid spheres, and they act more as waves."}, {"title": "Heisenberg\u2019s Uncertainty Principle .txt", "text": "In other words, they have both wavelike properties and solid properties."}, {"title": "Heisenberg\u2019s Uncertainty Principle .txt", "text": "And that means, because elementary particles are no longer solid spheres, there is no way to know its position and at the same time, its velocity with complete certainty."}, {"title": "Heisenberg\u2019s Uncertainty Principle .txt", "text": "So the formula or the equation for this uncertainty principle is the following plaques constant a very, very small number divided by two is always less than our change in x or the uncertainty of our position."}, {"title": "Heisenberg\u2019s Uncertainty Principle .txt", "text": "Change in position times mass times change in velocity."}, {"title": "Heisenberg\u2019s Uncertainty Principle .txt", "text": "Now remember, mass times velocity is momentum."}, {"title": "Heisenberg\u2019s Uncertainty Principle .txt", "text": "So this guy is change in momentum."}, {"title": "Heisenberg\u2019s Uncertainty Principle .txt", "text": "In other words, this is the uncertainty of our position and this is the uncertainty of our momentum or velocity."}, {"title": "Heisenberg\u2019s Uncertainty Principle .txt", "text": "And what this equation basically says is the following the less our change in axis, if this guy is very small, that means we know more information about our position, where our electron is located."}, {"title": "Heisenberg\u2019s Uncertainty Principle .txt", "text": "And that means if this guy decreases and this is a constant, this guy must increase, the smaller our change in excess, the more we know about our position, the greater our change in b is, the less we know about our velocity."}, {"title": "Heisenberg\u2019s Uncertainty Principle .txt", "text": "And likewise, the same holds the more we know about our velocity change in velocity."}, {"title": "Heisenberg\u2019s Uncertainty Principle .txt", "text": "The less our change in velocity is."}, {"title": "Heisenberg\u2019s Uncertainty Principle .txt", "text": "And the less we know about our change in x, the less we know about our position."}, {"title": "Heisenberg\u2019s Uncertainty Principle .txt", "text": "In other words, we can't be very certain about our position and at the same time about our velocity."}, {"title": "Heisenberg\u2019s Uncertainty Principle .txt", "text": "That's what the uncertainty principle tells us."}, {"title": "Heisenberg\u2019s Uncertainty Principle .txt", "text": "And this has to do with the duality nature of subatomic particles, electrons and protons, as well as a duality of light."}, {"title": "Heisenberg\u2019s Uncertainty Principle .txt", "text": "In other words, when you go from a large ball from this ball to a subatomic particle, our particle loses its solid sphere like properties."}, {"title": "Heisenberg\u2019s Uncertainty Principle .txt", "text": "It stops acting like a solid sphere and starts acting more like a wave."}, {"title": "Heisenberg\u2019s Uncertainty Principle .txt", "text": "And therefore, we can no longer pinpoint exactly where our object is and at the same time, what its velocity is, what its momentum."}, {"title": "Heisenberg\u2019s Uncertainty Principle .txt", "text": "The last thing I want to mention is the following this principle has nothing to do with how inaccurate or how accurate our instrument is, or how inaccurate or accurate our methods or experimental methods are."}, {"title": "Heisenberg\u2019s Uncertainty Principle .txt", "text": "In other words, even if we have the perfect instrument and our methods were the perfect methods, we still would not be able to pinpoint exactly where our object is, our electron is, and exactly with what velocity and in which direction our electron is traveling."}, {"title": "Heisenberg\u2019s Uncertainty Principle .txt", "text": "This principle has nothing to do with our instruments."}, {"title": "Heisenberg\u2019s Uncertainty Principle .txt", "text": "It is completely a byproduct of the nature of electrons, of the fact that electrons move as part particles and at the same time, they move as waves."}, {"title": "Fuel Cells .txt", "text": "In this lecture, we're going to look at something called fuel cells."}, {"title": "Fuel Cells .txt", "text": "Now, fuel cells are electrochemical cells that produce electrical work from oxidation of hydrogen."}, {"title": "Fuel Cells .txt", "text": "Now, fuel cells are very commonly used on spacecraft."}, {"title": "Fuel Cells .txt", "text": "They provide electricity to the various supply and system spacecrafts."}, {"title": "Fuel Cells .txt", "text": "So let's look at oxidation and reduction oxygen reactions found in a fuel cell."}, {"title": "Fuel Cells .txt", "text": "So our oxidation is as follows."}, {"title": "Fuel Cells .txt", "text": "A diatomic hydrogen is oxidized and it releases two H plus ions and two electrons."}, {"title": "Fuel Cells .txt", "text": "Our reduction reaction is as follows."}, {"title": "Fuel Cells .txt", "text": "A diatomic oxygen molecule takes up those two electrons and also takes up the two H plus ions forming water in a liquid state."}, {"title": "Fuel Cells .txt", "text": "Now, our neck reduction reaction is found by simply adding up these guys."}, {"title": "Fuel Cells .txt", "text": "We see that the H two plus ions cancel, the electrons cancel, and we have the following redox reaction."}, {"title": "Fuel Cells .txt", "text": "Now, our e is 0.7."}, {"title": "Fuel Cells .txt", "text": "Our cell potential for our fuel cell is zero 7 volts."}, {"title": "Fuel Cells .txt", "text": "It's positive."}, {"title": "Fuel Cells .txt", "text": "Now let's look at the layout of a fuel cell."}, {"title": "Fuel Cells .txt", "text": "A fuel cell, like any other electrochemical cell, has an anode and a cathode."}, {"title": "Fuel Cells .txt", "text": "It has a conductor that carries electrons from the anode to the cathode."}, {"title": "Fuel Cells .txt", "text": "And this is our outside system that receives electricity in the form of moving electrons."}, {"title": "Fuel Cells .txt", "text": "Now, like always, like most cases, our anode is negatively charged and out cathode is positively charged."}, {"title": "Fuel Cells .txt", "text": "And that's why electrons travel from the negative charge to the positive charge."}, {"title": "Fuel Cells .txt", "text": "Now, inside our anode, we need to allow H two molecules in the gas state in."}, {"title": "Fuel Cells .txt", "text": "And that's why we have an outside power source that allows those H two irons or H two molecules inside our anode."}, {"title": "Fuel Cells .txt", "text": "And to make sure our pressure is not increasing, make sure there's no build up in pressure, this needs to be released back into some outside location."}, {"title": "Fuel Cells .txt", "text": "That's why we have this guy on the bottom."}, {"title": "Fuel Cells .txt", "text": "So when this H two molecule enters our system, it is oxidized."}, {"title": "Fuel Cells .txt", "text": "But how is it oxidized?"}, {"title": "Fuel Cells .txt", "text": "Well, this brown layer is a platinum catalyst."}, {"title": "Fuel Cells .txt", "text": "And this platinum acts to catalyze or speed up that reaction going from our reacting to products."}, {"title": "Fuel Cells .txt", "text": "So when this guy in a our anode, it reacts with the platinum catalyst producing two moles of H plus ions and two moles of electrons."}, {"title": "Fuel Cells .txt", "text": "Now, these two moles of electrons travel via the conductor this way."}, {"title": "Fuel Cells .txt", "text": "Notice we have a membrane."}, {"title": "Fuel Cells .txt", "text": "And this membrane does not allow our electrons to pass from this anode to capital via this membrane."}, {"title": "Fuel Cells .txt", "text": "This membrane only allows H plus ions to flow or protons to flow."}, {"title": "Fuel Cells .txt", "text": "Now, why should we allow protons to flow?"}, {"title": "Fuel Cells .txt", "text": "Well, we'll talk about that in a bit."}, {"title": "Fuel Cells .txt", "text": "But notice some of the H or diatomic H must leave because we can't have a pressure build up in this system."}, {"title": "Fuel Cells .txt", "text": "So now we have the two electrons traveling all the way to this cathode."}, {"title": "Fuel Cells .txt", "text": "Now, when it travels through this guy, this guy provides electricity to some outside source."}, {"title": "Fuel Cells .txt", "text": "This is where the electrical work is done."}, {"title": "Fuel Cells .txt", "text": "Now, when this electron or two electrons travel all the way down to this cathode."}, {"title": "Fuel Cells .txt", "text": "These electrons react with the oxygen molecule, reducing it."}, {"title": "Fuel Cells .txt", "text": "But notice that in order for this build up of H plus ions not to occur, these H plus ions must pass to this side."}, {"title": "Fuel Cells .txt", "text": "So this, in a way, acts as a sole bridge because if this membrane wasn't here, we'd have a build up of positive charge here and a lack of positive charge here."}, {"title": "Fuel Cells .txt", "text": "And then that means our electrons will stop flowing."}, {"title": "Fuel Cells .txt", "text": "So to close the circuit, we need this membrane."}, {"title": "Fuel Cells .txt", "text": "And so these H plus ions travel from the anode to the cathode."}, {"title": "Fuel Cells .txt", "text": "And when they reach this position, they react with the oxygen and the electrons forming water."}, {"title": "Fuel Cells .txt", "text": "Now, this water needs to be released somewhere because if the water remains, there's a build up of water and now cell would eventually stop functioning."}, {"title": "Fuel Cells .txt", "text": "So this water leaves through some outside pump and is stored somewhere else."}, {"title": "Fuel Cells .txt", "text": "Now, notice, the same way we need to allow H two molecules inside our ano, we need to allow o two molecules inside our capital."}, {"title": "Fuel Cells .txt", "text": "And that's why we have this guy here."}, {"title": "Fuel Cells .txt", "text": "When this enters, when this oxygen enters the capital, it reacts with the H plus I the electrons coming in, and it forms our water."}, {"title": "Fuel Cells .txt", "text": "And this is a continuous process and it powers some outside source in this area here."}, {"title": "Fuel Cells .txt", "text": "So we have a few problems with our fuel cells."}, {"title": "Fuel Cells .txt", "text": "The first major problem is diatomic."}, {"title": "Fuel Cells .txt", "text": "H two molecule does not occur in nature."}, {"title": "Fuel Cells .txt", "text": "And it's very difficult and takes a lot of energy and money to generate."}, {"title": "Fuel Cells .txt", "text": "So it's very, very expensive."}, {"title": "Fuel Cells .txt", "text": "And that's why places like NASA use it."}, {"title": "Fuel Cells .txt", "text": "So it's probably a very bad idea to commercialize it because of its expense."}, {"title": "Fuel Cells .txt", "text": "The second issue with H two in the gas state is that it's very flammable."}, {"title": "Fuel Cells .txt", "text": "And that means it's very difficult to store."}, {"title": "Acidic Basic and Neutral Salts .txt", "text": "In this lecture, we're going to look at something called salts."}, {"title": "Acidic Basic and Neutral Salts .txt", "text": "Now, salts are formed whenever acids and bases react."}, {"title": "Acidic Basic and Neutral Salts .txt", "text": "So for example, let's look at a hypothetical reaction of a hypothetical acid and a hypothetical base."}, {"title": "Acidic Basic and Neutral Salts .txt", "text": "So we have HX plus MLH."}, {"title": "Acidic Basic and Neutral Salts .txt", "text": "So these guys associate to form the H ion, xion, Emion and hydroxide ion."}, {"title": "Acidic Basic and Neutral Salts .txt", "text": "So this H plus ion and the hydroxide ion will react to form water and this Xion and the Mion will react to form our salt."}, {"title": "Acidic Basic and Neutral Salts .txt", "text": "Now, different types of salts exist."}, {"title": "Acidic Basic and Neutral Salts .txt", "text": "Let's see what types of salts are formed when strong acids react with strong bases."}, {"title": "Acidic Basic and Neutral Salts .txt", "text": "So to illustrate this, let's see an example."}, {"title": "Acidic Basic and Neutral Salts .txt", "text": "So a strong acid, hydrochloric acid and a strong base, sodium hydroxide dissociate to form an H plus ion, a chloride ion, sodium ion and hydroxide ion."}, {"title": "Acidic Basic and Neutral Salts .txt", "text": "Now, in the same way that these guys react to form water, these two guys will react to form our water, while these two guys will react to former salt."}, {"title": "Acidic Basic and Neutral Salts .txt", "text": "Now, notice I wrote mutual salt."}, {"title": "Acidic Basic and Neutral Salts .txt", "text": "And in fact, strong acids and strong bases react to form Mutual Salt."}, {"title": "Acidic Basic and Neutral Salts .txt", "text": "And that's because our Final Solution has no presence of acids or bases."}, {"title": "Acidic Basic and Neutral Salts .txt", "text": "And let's see why."}, {"title": "Acidic Basic and Neutral Salts .txt", "text": "Well, this guy has a high Ka value because it's a strong acid."}, {"title": "Acidic Basic and Neutral Salts .txt", "text": "And this guy has a high KB value also because it's a strong base."}, {"title": "Acidic Basic and Neutral Salts .txt", "text": "And that means our equilibrium will lie all the way to the right."}, {"title": "Acidic Basic and Neutral Salts .txt", "text": "So in equilibrium, we're not going to have any of these guys present and we're not going to have any of this guy or this guy present due to these two assets and bases."}, {"title": "Acidic Basic and Neutral Salts .txt", "text": "Now, odor minization of water will still occur, but we're going to have the same concentration of this as this."}, {"title": "Acidic Basic and Neutral Salts .txt", "text": "So in our Final Solution, we're only going to have water and the neutral salt present, or just the salt present."}, {"title": "Acidic Basic and Neutral Salts .txt", "text": "And because our concentrations of H plus and oh minus are equal, this is a neutral salt."}, {"title": "Acidic Basic and Neutral Salts .txt", "text": "So combining these two guys to form this guy and this guy is the same thing as taking a cup of water and adding some salt inside."}, {"title": "Acidic Basic and Neutral Salts .txt", "text": "The result is the same as if you would take some hydrochloric acid and some sodium hydroxide, mix them and get this, the two results are the same."}, {"title": "Acidic Basic and Neutral Salts .txt", "text": "So let's see what types of salts are formed when strong bases and weak acids react."}, {"title": "Acidic Basic and Neutral Salts .txt", "text": "So once again, let's illustrate using an example."}, {"title": "Acidic Basic and Neutral Salts .txt", "text": "So acetic acid, a weak acid and sodium hydroxide, a strong base, react and dissociate into acetate ion, h plus ion, sodium ion, and hydroxide ion."}, {"title": "Acidic Basic and Neutral Salts .txt", "text": "Now, in the same way that these two guys form water, and these two guys from water, this guy and this guy will also form out of water."}, {"title": "Acidic Basic and Neutral Salts .txt", "text": "But now this acetate ion and this sodium will form a basic salt."}, {"title": "Acidic Basic and Neutral Salts .txt", "text": "So we see that strong bases and weak acids produce basic salts."}, {"title": "Acidic Basic and Neutral Salts .txt", "text": "Well, this has to do because of a hydrolysis reaction."}, {"title": "Acidic Basic and Neutral Salts .txt", "text": "And let's see what happens so this is a weak acid and that means its Ka will be low."}, {"title": "Acidic Basic and Neutral Salts .txt", "text": "So equilibrium for this guy will lie all the way to the left, not the right as in this case."}, {"title": "Acidic Basic and Neutral Salts .txt", "text": "That means at our solution, when our solution is formed, equilibrium, we're going to have some of these guys present, right?"}, {"title": "Acidic Basic and Neutral Salts .txt", "text": "We're going to have a bunch of these guys present."}, {"title": "Acidic Basic and Neutral Salts .txt", "text": "And that means at equilibrium, we're not only going to have water and salt, we're also going to have this guy present."}, {"title": "Acidic Basic and Neutral Salts .txt", "text": "So we're going to have this ion, acetate ion, and our water molecule from here."}, {"title": "Acidic Basic and Neutral Salts .txt", "text": "And these guys will now react because this will act as an acid and this will act as a base, right?"}, {"title": "Acidic Basic and Neutral Salts .txt", "text": "Because this is a conjugate base of this acid."}, {"title": "Acidic Basic and Neutral Salts .txt", "text": "And because this conjugate acid is weak, this conjugate base is strong."}, {"title": "Acidic Basic and Neutral Salts .txt", "text": "And that means it will react with water to form back deciding acid and a hydroxide ion."}, {"title": "Acidic Basic and Neutral Salts .txt", "text": "And this hydroxide ion is what creates the basic solution."}, {"title": "Acidic Basic and Neutral Salts .txt", "text": "And because we have a basic solution, we're going to have the basic salt."}, {"title": "Acidic Basic and Neutral Salts .txt", "text": "So a times strong bases react with weak acids, we produce basic salts."}, {"title": "Acidic Basic and Neutral Salts .txt", "text": "Now, how basic our salt is depends on the KB value of our reaction."}, {"title": "Acidic Basic and Neutral Salts .txt", "text": "The higher the KB value, the stronger this base."}, {"title": "Acidic Basic and Neutral Salts .txt", "text": "And that means the more basic our salt."}, {"title": "Acidic Basic and Neutral Salts .txt", "text": "So let's look at what types of salts are formed when strong acids react with weak bases."}, {"title": "Acidic Basic and Neutral Salts .txt", "text": "So let's examine the following example."}, {"title": "Acidic Basic and Neutral Salts .txt", "text": "Hydrochloric acid, a strong acid reacts with ammonia, a weak base, and in the presence of water, that they associate into H plus ion, a chloride ion."}, {"title": "Acidic Basic and Neutral Salts .txt", "text": "And our ammonia."}, {"title": "Acidic Basic and Neutral Salts .txt", "text": "Now ammonia reacts with H to create Ammonium, a positively charged ion."}, {"title": "Acidic Basic and Neutral Salts .txt", "text": "Now this positively charged ion then reacts with the chloride to neutralize the charge, creating an acidic salt."}, {"title": "Acidic Basic and Neutral Salts .txt", "text": "Now, since we begin with water, we also have water at the end result."}, {"title": "Acidic Basic and Neutral Salts .txt", "text": "Now let's examine why we have an acidic salt."}, {"title": "Acidic Basic and Neutral Salts .txt", "text": "Remember, we begin with a weak acid that has a low KB value."}, {"title": "Acidic Basic and Neutral Salts .txt", "text": "And that means equilibrium will be far to the left."}, {"title": "Acidic Basic and Neutral Salts .txt", "text": "Our reactants will be favored, or at least our ammonia will be favored."}, {"title": "Acidic Basic and Neutral Salts .txt", "text": "So that means this weak base has a strong or relatively strong conjugate acid."}, {"title": "Acidic Basic and Neutral Salts .txt", "text": "So what happens when our conjugate acid is formed?"}, {"title": "Acidic Basic and Neutral Salts .txt", "text": "What happens when Ammonium is formed, when this guy combines with this guy?"}, {"title": "Acidic Basic and Neutral Salts .txt", "text": "Well, we get ammonia and Ammonium will not want to exist in this state because it's a relatively strong conjugate acid."}, {"title": "Acidic Basic and Neutral Salts .txt", "text": "So it will want to dissociate back into our ammonia."}, {"title": "Acidic Basic and Neutral Salts .txt", "text": "But now it dissociates back into ammonia in the presence of water."}, {"title": "Acidic Basic and Neutral Salts .txt", "text": "And when water is in the mixture, what happens?"}, {"title": "Acidic Basic and Neutral Salts .txt", "text": "Well, this guy is an acid, so this guy must be a base."}, {"title": "Acidic Basic and Neutral Salts .txt", "text": "And our base will accept the H ion forming back our ammonia and creating hydronium."}, {"title": "Acidic Basic and Neutral Salts .txt", "text": "So now, equilibrium, we're going to have more hydronium."}, {"title": "Acidic Basic and Neutral Salts .txt", "text": "And that means our acidity of our solution will increase."}, {"title": "Acidic Basic and Neutral Salts .txt", "text": "So our salt will be acidic."}, {"title": "Acidic Basic and Neutral Salts .txt", "text": "Therefore, we see that conjugate acid determines the PH of our solution."}, {"title": "Acidic Basic and Neutral Salts .txt", "text": "And the higher the K. A, the stronger our conjugate acid and the more acidic our salt or the more acidic our solution."}, {"title": "Acidic Basic and Neutral Salts .txt", "text": "Now, that means whenever we mix strong acids and weak bases, we create acidic salt."}, {"title": "Acidic Basic and Neutral Salts .txt", "text": "So let's look at what types of salts are created when weak bases and weak acids are reactive."}, {"title": "Acidic Basic and Neutral Salts .txt", "text": "So there is actually a competition between the conjugate acid and the conjugate base."}, {"title": "Acidic Basic and Neutral Salts .txt", "text": "And both Ka and KB must be considered."}, {"title": "Acidic Basic and Neutral Salts .txt", "text": "Now, if Ka wins or our conjugate acid wins, we get an acidic solution or an acidic salt."}, {"title": "Acidic Basic and Neutral Salts .txt", "text": "And if our KB wins, then we get a basic solution or a basic salt."}, {"title": "Intro to Quantum Mechanics .txt", "text": "Now, in this lecture, I'm going to give a very, very brief introduction to quantum mechanics."}, {"title": "Intro to Quantum Mechanics .txt", "text": "The reason this branch of physics is important in chemistry is it becomes important when we talk about quantum numbers and the photoelectric effect."}, {"title": "Intro to Quantum Mechanics .txt", "text": "Now, quantum mechanics is the study of microscopic phenomena such as electromagnetic magnetic waves and the study of subatomic particles such as electrons, protons, neutrons, et cetera."}, {"title": "Intro to Quantum Mechanics .txt", "text": "Now, the main idea, the main conclusion that we get from quantum mechanics is the following tiny subatomic particles called electrons and protons and neutrons and other particles."}, {"title": "Intro to Quantum Mechanics .txt", "text": "Now, subatomic simply means smaller than an atom gain or lose energy in discrete amount called photons."}, {"title": "Intro to Quantum Mechanics .txt", "text": "Now, we're going to talk more about photons and what they are when we'll talk about the photoelectric effect."}, {"title": "Intro to Quantum Mechanics .txt", "text": "Now, this statement is analogous to the following everyday situation."}, {"title": "Intro to Quantum Mechanics .txt", "text": "Suppose we have a vending machine."}, {"title": "Intro to Quantum Mechanics .txt", "text": "And this vending machine only accepts coins that are $0.25."}, {"title": "Intro to Quantum Mechanics .txt", "text": "So it won't accept two coins."}, {"title": "Intro to Quantum Mechanics .txt", "text": "It won't accept five cent coins."}, {"title": "Intro to Quantum Mechanics .txt", "text": "It won't accept dollar bills."}, {"title": "Intro to Quantum Mechanics .txt", "text": "It only accepts a single coin known as the quarter."}, {"title": "Intro to Quantum Mechanics .txt", "text": "Now, in the same analogous way, electrons and protons and neutrons and other subatomic particles accept energy bursts this feet amount called a photon."}, {"title": "Intro to Quantum Mechanics .txt", "text": "Now, one other result from quantum mechanics is the following."}, {"title": "Intro to Quantum Mechanics .txt", "text": "Electromagnetic waves, such as as light waves, have dual natures."}, {"title": "Intro to Quantum Mechanics .txt", "text": "In other words, they can act as both a particle and as a wave."}, {"title": "Intro to Quantum Mechanics .txt", "text": "And we'll talk more about that when we'll talk about the photoelectric effect."}, {"title": "Average Kinetic Energy and Root Mean Square Velocity .txt", "text": "So we already spoke about the root mean square velocity of any set of points."}, {"title": "Average Kinetic Energy and Root Mean Square Velocity .txt", "text": "Now, we're going to look specifically at the root mean square velocity for gases."}, {"title": "Average Kinetic Energy and Root Mean Square Velocity .txt", "text": "Now, in gases, root mean square velocity is given by the following formula, which can be derived using calculus."}, {"title": "Average Kinetic Energy and Root Mean Square Velocity .txt", "text": "Now, I will spare you the calculus and simply give you the formula."}, {"title": "Average Kinetic Energy and Root Mean Square Velocity .txt", "text": "But if you're curious about where this formula comes from, leave A comment and I'll Show you."}, {"title": "Average Kinetic Energy and Root Mean Square Velocity .txt", "text": "So, VRMs is equal to the square root of three times R times T divided by M, where M is our molar mass of gas, t is our temperature in Kelvin, and R is the molar gas constant."}, {"title": "Average Kinetic Energy and Root Mean Square Velocity .txt", "text": "Now, my goal is I want to use this VRMs to find the average kinetic energy."}, {"title": "Average Kinetic Energy and Root Mean Square Velocity .txt", "text": "Because remember, kinetic energy of anything is given by one half times mass times V squared."}, {"title": "Average Kinetic Energy and Root Mean Square Velocity .txt", "text": "Now, to find the kinetic average, I basically plug in my Dr meh into my D, and that will give me the average, because remember, this guy is the average or the quadratic average of my sets of points."}, {"title": "Average Kinetic Energy and Root Mean Square Velocity .txt", "text": "So average kinetic energy is equal to one half times and times VR mass squared equals one half times mass."}, {"title": "Average Kinetic Energy and Root Mean Square Velocity .txt", "text": "Now, I take my formula for BRMs, for Dances, and plug into my equation."}, {"title": "Average Kinetic Energy and Root Mean Square Velocity .txt", "text": "The radical will disappear, because the radical has an exponent of a half a half times two is one."}, {"title": "Average Kinetic Energy and Root Mean Square Velocity .txt", "text": "So I simply get one half times mass over molam mass times R and T. Now, remember, molar mass has units of mass divided by moles."}, {"title": "Average Kinetic Energy and Root Mean Square Velocity .txt", "text": "So the mass will cancel, and moles will go on top, and we'll get one half the mass will cancel."}, {"title": "Average Kinetic Energy and Root Mean Square Velocity .txt", "text": "So this M and this M will cancel."}, {"title": "Average Kinetic Energy and Root Mean Square Velocity .txt", "text": "The moles will go on top, and we'll have R times T. So my file final representation of my kinetic or average kinetic energy is three times N times R times T divided by two, where N is our number of moles."}, {"title": "Average Kinetic Energy and Root Mean Square Velocity .txt", "text": "So Suppose we have 1 mol of any gas."}, {"title": "Average Kinetic Energy and Root Mean Square Velocity .txt", "text": "Well, since we have 1 Mol, our N will be one."}, {"title": "Average Kinetic Energy and Root Mean Square Velocity .txt", "text": "And for 1 Mol, our formula becomes average kinetic energy of 1 mol of gas."}, {"title": "Average Kinetic Energy and Root Mean Square Velocity .txt", "text": "That's equal to three times R times T divided by two."}, {"title": "Average Kinetic Energy and Root Mean Square Velocity .txt", "text": "So the only non constant in this equation is T. So we see kinetic energy depends strictly on temperature, or 1 mol of gas depends strictly on the temperature."}, {"title": "Average Kinetic Energy and Root Mean Square Velocity .txt", "text": "Now, suppose instead I want to find one molecule."}, {"title": "Average Kinetic Energy and Root Mean Square Velocity .txt", "text": "What's the kinetic average of one molecule of gas?"}, {"title": "Average Kinetic Energy and Root Mean Square Velocity .txt", "text": "Not 1 mol."}, {"title": "Average Kinetic Energy and Root Mean Square Velocity .txt", "text": "Well, remember, a mole has an avocado's number of molecules."}, {"title": "Average Kinetic Energy and Root Mean Square Velocity .txt", "text": "So I simply take my formula and divide it by N. So three times R times two divided by two N. The reason I singled out the R and the N is because this guy is known as a Boltzmann constant."}, {"title": "Average Kinetic Energy and Root Mean Square Velocity .txt", "text": "In other words, scientists use some value k that equals r divided by n. So we replace this R divided by n with k called the Bolton constant, and our equation becomes three times k times t over two."}, {"title": "Average Kinetic Energy and Root Mean Square Velocity .txt", "text": "Which is the same thing as saying three times R times t divided by two times n.\nSo once again, for one molecule, a single molecule, to find the kinetic average of that molecule, we simply use this formula where k is at boltsman constant."}, {"title": "Average Kinetic Energy and Root Mean Square Velocity .txt", "text": "Now, to find the average kinetic energy of a mole of molecules, we have to use this formula."}, {"title": "Average Kinetic Energy and Root Mean Square Velocity .txt", "text": "Now note that at any given time, our molecule can have any kinetic energy."}, {"title": "Average Kinetic Energy and Root Mean Square Velocity .txt", "text": "But on average, a mole of molecules will have this much energy."}, {"title": "Average Kinetic Energy and Root Mean Square Velocity .txt", "text": "And on average, a molecule within this mole will have this much kinetic energy."}, {"title": "Colloids .txt", "text": "Colloids are mixtures of two or more compounds found in different states."}, {"title": "Colloids .txt", "text": "That means that they are nonhomogeneous solutions."}, {"title": "Colloids .txt", "text": "Recall that a homogeneous solution is a solution in which the compounds that compose the mixture are in the same state while colloids are composed of compounds in different states."}, {"title": "Colloids .txt", "text": "Now, they also contain larger solid particles."}, {"title": "Colloids .txt", "text": "For example, blood, which is a colloid, is composed mostly of water and hemoglobin."}, {"title": "Colloids .txt", "text": "Hemoglobin is the larger particle, the solute, while water is a solvent, okay?"}, {"title": "Colloids .txt", "text": "Now, the larger particles are also called colloidal particles."}, {"title": "Colloids .txt", "text": "So hemoglobin is the colloidal particle."}, {"title": "Colloids .txt", "text": "Now, other examples of colloids exist."}, {"title": "Colloids .txt", "text": "Fog."}, {"title": "Colloids .txt", "text": "Fog is composed of liquid particles found in the gas state."}, {"title": "Colloids .txt", "text": "Smoke is composed of solid particles or carbon, found in the gas state."}, {"title": "Colloids .txt", "text": "Wood cream is composed of gas particles found in the liquid state."}, {"title": "Colloids .txt", "text": "And paint is composed of solid particles found in the liquid state."}, {"title": "Colloids .txt", "text": "Now, carbon systems also experience something called a Tyndall effect."}, {"title": "Colloids .txt", "text": "The tyle effect is a scattering of light due to the presence of large particles."}, {"title": "Colloids .txt", "text": "Now, if you look at this system here, pretend that this is a cup and inside is a colloidal system, okay?"}, {"title": "Colloids .txt", "text": "And these are the colloidal particles or the large particles."}, {"title": "Colloids .txt", "text": "Now, when light will enter it's going to bounce back and forth between these particles and it's going to lose energy."}, {"title": "Colloids .txt", "text": "Eventually, when it comes out, it's going to come out with less energy because remember, light carries energy."}, {"title": "Colloids .txt", "text": "Light is composed of photons."}, {"title": "Colloids .txt", "text": "That means that the system, the colloidal system will be translucent so you won't be able to see through it very clearly."}, {"title": "Colloids .txt", "text": "The solid portion of the colloid is called a continuous phase."}, {"title": "Colloids .txt", "text": "The solid portion of the colloid is called dispersed phase."}, {"title": "Colloids .txt", "text": "Now, when water is a solvent, classification occurs in two ways."}, {"title": "Colloids .txt", "text": "Lyophilicaloids are those colloids that have strong attractions between continuous and dispersed phases."}, {"title": "Colloids .txt", "text": "Examples include protein water, which is found in blood."}, {"title": "Colloids .txt", "text": "Protein is a dispersed phase."}, {"title": "Colloids .txt", "text": "Water is a continuous phase and they mix very well."}, {"title": "Colloids .txt", "text": "Biophobic colloids are those colloids that lack attraction between continuous and dispersed phases."}, {"title": "Colloids .txt", "text": "And examples include fat and water mixtures."}, {"title": "Colloids .txt", "text": "We know that fat, the dispersed phase and water continuous days don't mix very well."}, {"title": "Colloids .txt", "text": "Now, there are two ways to filter colloids."}, {"title": "Colloids .txt", "text": "The first way is by heating and then filtration."}, {"title": "Colloids .txt", "text": "If you heat a colloid, this will cause the salute to coagulate and then you could filter it by simple filtration."}, {"title": "Colloids .txt", "text": "The second way is via dialysis."}, {"title": "Colloids .txt", "text": "Dialysis is a separation using a semi permeable membrane."}, {"title": "Colloids .txt", "text": "For example, you have a semi permeable membrane here."}, {"title": "Colloids .txt", "text": "Red blood cells mixed with water."}, {"title": "Colloids .txt", "text": "The red blood cells are the dispersed phase."}, {"title": "Colloids .txt", "text": "The water is a continuous phase."}, {"title": "Colloids .txt", "text": "Water will flow easily for one side is next."}, {"title": "Colloids .txt", "text": "The red blood cells are too big to pass so they will be left behind on this side."}, {"title": "Cell voltage example .txt", "text": "So we begin with a certain electrochemical cell that's composed of cadmium and zinc."}, {"title": "Cell voltage example .txt", "text": "Now, we are given the cell voltage or the electromotive force around cells, and it's given to be zero point 36 volts."}, {"title": "Cell voltage example .txt", "text": "Under standard conditions, that means 1 bar pressure and one molar concentration."}, {"title": "Cell voltage example .txt", "text": "Now, this guy is also at 25 degrees Celsius."}, {"title": "Cell voltage example .txt", "text": "So we are also given the cell voltage for one of the two half reactions, one of the two half cells."}, {"title": "Cell voltage example .txt", "text": "And the zinc half reaction is given negative zero point 76 volts."}, {"title": "Cell voltage example .txt", "text": "We want to find our goal is to find the cell voltage for the other half cell for the other half reaction."}, {"title": "Cell voltage example .txt", "text": "So, in the first step, we begin our problem by writing their reduction reaction for the entire equation for the entire process."}, {"title": "Cell voltage example .txt", "text": "So, solid zinc reacts with cadmium ions to produce aqueous zinc and solid cadmium."}, {"title": "Cell voltage example .txt", "text": "So let's figure out which one is oxidized and which one is reduced."}, {"title": "Cell voltage example .txt", "text": "This will help us place the metal that belongs to the anode and the metal that belongs to the cathode."}, {"title": "Cell voltage example .txt", "text": "So, zinc solid goes from a neutral charge to a plus two charge."}, {"title": "Cell voltage example .txt", "text": "That means it loses electrons."}, {"title": "Cell voltage example .txt", "text": "So that means it is oxidized."}, {"title": "Cell voltage example .txt", "text": "It's a reducing agent."}, {"title": "Cell voltage example .txt", "text": "Now, this guy cadmium ion goes from an ion to a neutral charge, and that means this guy is reduced."}, {"title": "Cell voltage example .txt", "text": "So it's the oxidizing agent."}, {"title": "Cell voltage example .txt", "text": "It gains those electrons that are released by this zinc solid metal."}, {"title": "Cell voltage example .txt", "text": "So that means in step two, when we draw our electrochemical cell, the first half cell will contain our zinc solid."}, {"title": "Cell voltage example .txt", "text": "And that's because zinc is oxidized, and the anode always contains the oxidation reaction."}, {"title": "Cell voltage example .txt", "text": "So this is our zinc metal."}, {"title": "Cell voltage example .txt", "text": "That means this must be our cadmium metal."}, {"title": "Cell voltage example .txt", "text": "And so electrons will travel via the conductor, via this volt meter and into this cathode, into this electrode."}, {"title": "Cell voltage example .txt", "text": "The volt meter, by the way, is the thing that reads zero point 36 volts."}, {"title": "Cell voltage example .txt", "text": "So this sold bridge is placed here because it plays the role of closing the circuit."}, {"title": "Cell voltage example .txt", "text": "Without the sole bridge, this guy would not function."}, {"title": "Cell voltage example .txt", "text": "Electrons would not flow, and it's very important."}, {"title": "Cell voltage example .txt", "text": "So, once again, our anode, our place where oxidation occurs, and our cathode, the place where reduction occurs."}, {"title": "Cell voltage example .txt", "text": "So electrons travel from this way, from this electrode to this electrode."}, {"title": "Cell voltage example .txt", "text": "So when they leave this cell, this solid zinc releases electrons, right?"}, {"title": "Cell voltage example .txt", "text": "Electrons begin to flow here."}, {"title": "Cell voltage example .txt", "text": "It also releases a zinc ion into this solution."}, {"title": "Cell voltage example .txt", "text": "And when the electrons travel this way, they combine."}, {"title": "Cell voltage example .txt", "text": "When they reach this metal, they combine with the cadmium ions forming our cadmium solid."}, {"title": "Cell voltage example .txt", "text": "So, in the third step, we basically want to use this cell voltage formula to find our cell voltage for the cathode."}, {"title": "Cell voltage example .txt", "text": "Remember?"}, {"title": "Cell voltage example .txt", "text": "Now, we know that this guy, this value of negative zero point 76 represents the value for the anode."}, {"title": "Cell voltage example .txt", "text": "So we use this formula to solve for our cathode."}, {"title": "Cell voltage example .txt", "text": "So we know our 0.36 volts, which is told by the voltmeter."}, {"title": "Cell voltage example .txt", "text": "Now, this we don't know."}, {"title": "Cell voltage example .txt", "text": "So we let a DX minus now in parentheses we have a negative 0.76 volts, right?"}, {"title": "Cell voltage example .txt", "text": "So negative and negative becomes a positive."}, {"title": "Cell voltage example .txt", "text": "Then we subtract both sides by this guy and we get x to be 0.36\n-0.76 volts gives us negative 0.4 volts."}, {"title": "Cell voltage example .txt", "text": "So this is our cell voltage for the cathode cell for the cadmium for that reduction reaction of cadmium."}, {"title": "Charles Law .txt", "text": "Now we already spoke about a concept called the Kinetic Molecular Theory of Gases."}, {"title": "Charles Law .txt", "text": "And what this theory did for us is it helped us gain more intuition about how individual gas molecules interact on a very small microscopic level."}, {"title": "Charles Law .txt", "text": "Now we also spoke about a law called Boils Law."}, {"title": "Charles Law .txt", "text": "And what Boils Law did for us is it helps help us gain more intuition about the macroscopic behavior of gases."}, {"title": "Charles Law .txt", "text": "In other words, what happens at constant temperature when we take a balloon filled with air and squeeze it."}, {"title": "Charles Law .txt", "text": "Well, we said that, and Boyle's Law explained this, that when we squeeze the balloon, we decrease volume, increase pressure, and eventually our balloon will pop."}, {"title": "Charles Law .txt", "text": "Now we're going to look at another law called Charles Law which also helps us explain the macroscopic large scale behavior of many gas molecules and how they interact with one another and with our system."}, {"title": "Charles Law .txt", "text": "So for Charles Law to work, two conditions must hold."}, {"title": "Charles Law .txt", "text": "We must have constant pressure and we must have constant number of molecules."}, {"title": "Charles Law .txt", "text": "So our N number of moles stays the same."}, {"title": "Charles Law .txt", "text": "And what Charles Law does is it relates volume and temperature."}, {"title": "Charles Law .txt", "text": "Remember Boyle's Law related volume and pressure?"}, {"title": "Charles Law .txt", "text": "Well, Charles Law relates temperature and volume when pressure is constant."}, {"title": "Charles Law .txt", "text": "And what it says is that volume is directly proportional to temperature."}, {"title": "Charles Law .txt", "text": "And this means if we bring the T over or if we multiply a constant by T and we bring T over, what we get is the following v divided by T is equal to a constant."}, {"title": "Charles Law .txt", "text": "Remember, in Boyle's Law we saw that P times V gave us a constant and that if we increase pressure, our volume must decrease while keeping the constant the same."}, {"title": "Charles Law .txt", "text": "Well, in this case, we have the same kind of situation, except now we have volume divided by temperature."}, {"title": "Charles Law .txt", "text": "In other words."}, {"title": "Charles Law .txt", "text": "Now for this constant to remain a constant and not change if we increase volume, say by two, our temperature also must increase by the same amount by two."}, {"title": "Charles Law .txt", "text": "So whenever we increase volume, we increase temperature."}, {"title": "Charles Law .txt", "text": "Or if we decrease volume, we must decrease the temperature for this guy to remain constant."}, {"title": "Charles Law .txt", "text": "Now notice this constant remains or depends on two things on the pressure and on the number of molecules."}, {"title": "Charles Law .txt", "text": "For example, if we have more molecules, our constant will be higher."}, {"title": "Charles Law .txt", "text": "And we'll learn more about that when we talk about the ideal gas law."}, {"title": "Charles Law .txt", "text": "For now, it's sufficient to say that our cost depends on both of these guys."}, {"title": "Charles Law .txt", "text": "So the same way we did for Boyle's Law, for Charles Law, we can rewrite this relation or this relation in the following manner."}, {"title": "Charles Law .txt", "text": "Now, suppose I have some system, some gas system and I have two sets of different conditions for this gas system."}, {"title": "Charles Law .txt", "text": "Well, I can relate them in the following manner."}, {"title": "Charles Law .txt", "text": "Assuming that these guys are both constant."}, {"title": "Charles Law .txt", "text": "In other words, note that the constant always stays the same when our pressure number of moles stays the same."}, {"title": "Charles Law .txt", "text": "That means if we have some conditions, v one and T one and a second condition of V two and T two."}, {"title": "Charles Law .txt", "text": "And these two conditions are under the same pressure and number of moles, that means our constant will be the same."}, {"title": "Charles Law .txt", "text": "And so I can say V one over T one equals V two over t two equals that same constant."}, {"title": "Charles Law .txt", "text": "So once again, for a gas sample with two different sets of T's and Vs for two different conditions, this is our law."}, {"title": "Charles Law .txt", "text": "This is our Charles Law."}, {"title": "Charles Law .txt", "text": "Now, whenever we talk about gases, and we talk about these different laws that revolve around gases, our temperature is never in Celsius, it's only in Kelvin."}, {"title": "Charles Law .txt", "text": "And that means we have to convert Celsius to Kelvin."}, {"title": "Charles Law .txt", "text": "And this is how you do it."}, {"title": "Charles Law .txt", "text": "To get the Kelvin temperature, you take the Celsius temperature and you add 273.15 to it."}, {"title": "Charles Law .txt", "text": "For example, if our Celsius temperature is ten degrees Celsius, I simply add 273.15 and I get 283.15 Kelvin."}, {"title": "Charles Law .txt", "text": "That's our temperature in Kelvin."}, {"title": "Charles Law .txt", "text": "So let's think of an example where Charles Law is evident."}, {"title": "Charles Law .txt", "text": "So suppose it's someone's birthday and it's winter."}, {"title": "Charles Law .txt", "text": "So it's cold outside and you need to go and buy somebody a present."}, {"title": "Charles Law .txt", "text": "So he decides to buy a balloon."}, {"title": "Charles Law .txt", "text": "So you go inside the store, you fill up the balloon with some helium."}, {"title": "Charles Law .txt", "text": "Now suppose once you fill the balloon up, there are no holes in the balloon."}, {"title": "Charles Law .txt", "text": "So the number of moles or number of molecules inside our balloon remains constant."}, {"title": "Charles Law .txt", "text": "Also, let's suppose that our pressure inside the store and outside is one ATM atmospheric pressure."}, {"title": "Charles Law .txt", "text": "So let's suppose that our pressure is also constant."}, {"title": "Charles Law .txt", "text": "Now, obviously, if it's winter, it's much colder outside than inside."}, {"title": "Charles Law .txt", "text": "So suppose I fill up my balloon with N number of moles of helium, and suppose now I go outside with that balloon."}, {"title": "Charles Law .txt", "text": "Well, on the inside, inside the store, we were at one condition."}, {"title": "Charles Law .txt", "text": "We had some D two and t two, right?"}, {"title": "Charles Law .txt", "text": "Once we step outside, our temperature drops."}, {"title": "Charles Law .txt", "text": "So what happens to volume?"}, {"title": "Charles Law .txt", "text": "Well, according to Charles Law, this guy states that if we go outside and my temperature drops, then my volume must drop as well to make sure that our constant stays the same."}, {"title": "Charles Law .txt", "text": "That means if I go outside with my balloon, my balloon will shrivel, it will become smaller, and that's because of Charles Law."}, {"title": "Charles Law .txt", "text": "So once again, we see how macro scale events are explained by Charles Law, just like they were explained by Boyle's Law."}, {"title": "Charles Law .txt", "text": "So we have yet another law that helps us explain how gas molecules behave when we have a lot of them together, not simply individual gas molecules."}, {"title": "Charles Law .txt", "text": "Now, we can, of course, explain how Charles Law functions on an individual level using the kinetic theory."}, {"title": "Charles Law .txt", "text": "Now, kinetic theory explains Charles Law on a microscopic level at constant pressure."}, {"title": "Charles Law .txt", "text": "So we have constant pressure, right?"}, {"title": "Charles Law .txt", "text": "Our pressure doesn't change."}, {"title": "Charles Law .txt", "text": "So if our temperature increases, what happens to the molecules?"}, {"title": "Charles Law .txt", "text": "The molecules gain more kinetic energy."}, {"title": "Charles Law .txt", "text": "And if they gain more kinetic energy, they gain more speed."}, {"title": "Charles Law .txt", "text": "They become quicker."}, {"title": "Charles Law .txt", "text": "And that means the only way that our pressure stays constant with higher kinetic energy is if the volume expands."}, {"title": "Charles Law .txt", "text": "So that's exactly what happens."}, {"title": "Charles Law .txt", "text": "In order to ensure that there is constant pressure."}, {"title": "Charles Law .txt", "text": "An increase in temperature means there's an increase in kinetic energy."}, {"title": "Charles Law .txt", "text": "And this increase in kinetic energy means that there are more molecules, or the molecules are pushing against the wall of the container with greater force."}, {"title": "Charles Law .txt", "text": "And so they must expand container, increase the volume."}, {"title": "Charles Law .txt", "text": "So let's look at the graph of volume times our temperature."}, {"title": "Charles Law .txt", "text": "Now."}, {"title": "Charles Law .txt", "text": "Temperature here is in Kelvin."}, {"title": "Charles Law .txt", "text": "So our origin is at zero."}, {"title": "Charles Law .txt", "text": "Zero?"}, {"title": "Charles Law .txt", "text": "Remember, we can't have negative volume."}, {"title": "Charles Law .txt", "text": "Our small volume of zero is zero, so can't go below this."}, {"title": "Charles Law .txt", "text": "Now our temperature in Kelvin is zero."}, {"title": "Charles Law .txt", "text": "So we saw it as zero."}, {"title": "Charles Law .txt", "text": "Zero?"}, {"title": "Charles Law .txt", "text": "At zero volume."}, {"title": "Charles Law .txt", "text": "We have zero Kelvin."}, {"title": "Charles Law .txt", "text": "But remember, zero Kelvin is unattainable."}, {"title": "Charles Law .txt", "text": "Everything has volume."}, {"title": "Charles Law .txt", "text": "And that means our temperature must be somewhere above zero."}, {"title": "Charles Law .txt", "text": "Also notice that v one over t one means that our t one can't be zero."}, {"title": "Charles Law .txt", "text": "Otherwise, we get an undefined number, a number that has infinity as its answer."}, {"title": "Charles Law .txt", "text": "Because any number over zero is infinity."}, {"title": "Charles Law .txt", "text": "So let's look at this law."}, {"title": "Charles Law .txt", "text": "Why is it that we have a linear function?"}, {"title": "Charles Law .txt", "text": "Linear line?"}, {"title": "Charles Law .txt", "text": "Well, that's because this is our slope."}, {"title": "Charles Law .txt", "text": "A constant slope."}, {"title": "Charles Law .txt", "text": "So this guy's constant."}, {"title": "Charles Law .txt", "text": "Whenever D increases, team must increase by the same amount."}, {"title": "Charles Law .txt", "text": "If this is doubled, this is doubled."}, {"title": "Charles Law .txt", "text": "If this is tripled, this is tripled and so on."}, {"title": "Charles Law .txt", "text": "That's why there is a linear relationship between D and T.\nAnd this is how our graph for Charles Law will look when we grab volume versus temperature."}, {"title": "Sp Hybridization.txt", "text": "So, in this lecture, we're going to begin a discussion on a process in organic chemistry known as orbital hybridization."}, {"title": "Sp Hybridization.txt", "text": "So let's begin with the following depiction."}, {"title": "Sp Hybridization.txt", "text": "In our first case, let's suppose we have two different atoms."}, {"title": "Sp Hybridization.txt", "text": "The first atom donates an S orbital, and the second atom donates a p orbital."}, {"title": "Sp Hybridization.txt", "text": "So these two orbitals will combine in a way to form the following molecular orbitals."}, {"title": "Sp Hybridization.txt", "text": "So, because we input two, we should get back to orbitals."}, {"title": "Sp Hybridization.txt", "text": "And that's exactly what we get."}, {"title": "Sp Hybridization.txt", "text": "The first molecular orbital is known as the bonding molecular orbital."}, {"title": "Sp Hybridization.txt", "text": "It's lower in energy."}, {"title": "Sp Hybridization.txt", "text": "And the second one is known as the anti bonding molecular orbital."}, {"title": "Sp Hybridization.txt", "text": "It's the one higher in energy."}, {"title": "Sp Hybridization.txt", "text": "So that's the first case."}, {"title": "Sp Hybridization.txt", "text": "That's the normal case that we're used to seeing."}, {"title": "Sp Hybridization.txt", "text": "So let's suppose we try a different thing."}, {"title": "Sp Hybridization.txt", "text": "Now, let's suppose we have a single atom."}, {"title": "Sp Hybridization.txt", "text": "And that single atom has both an S orbital as well as a p orbital."}, {"title": "Sp Hybridization.txt", "text": "What happens is, within that single atom, these two orbitals can combine in such a way to produce something that we know as hybridized orbitals."}, {"title": "Sp Hybridization.txt", "text": "In other words, we have a single atom."}, {"title": "Sp Hybridization.txt", "text": "Within that single atom, an S orbital interacts with a p orbital to produce two hybridized orbitals."}, {"title": "Sp Hybridization.txt", "text": "Now, once again, we input two orbitals."}, {"title": "Sp Hybridization.txt", "text": "So we should get back to hybridized orbitals."}, {"title": "Sp Hybridization.txt", "text": "And that's exactly what we see happen here."}, {"title": "Sp Hybridization.txt", "text": "Now, when this S combines with this positive P, we get the following hybridized orbitals."}, {"title": "Sp Hybridization.txt", "text": "In other words, this positive region simply combines with this positive region, and this becomes smaller."}, {"title": "Sp Hybridization.txt", "text": "So a positive S orbital combines with a positive p orbital."}, {"title": "Sp Hybridization.txt", "text": "The two greens combine, the blue becomes smaller to form an enlarged positive green lobe and a smaller or thinner negative blue lobe."}, {"title": "Sp Hybridization.txt", "text": "And the same happens when this part is negative."}, {"title": "Sp Hybridization.txt", "text": "We get the following because two negative lobes combine to form this enlarged negative section, enlarged negative lobe, and the smaller positive green lobe."}, {"title": "Sp Hybridization.txt", "text": "Now, in this lecture, we're going to only talk about SP hypersized orbitals."}, {"title": "Sp Hybridization.txt", "text": "In future lectures, we're also going to talk about SP two and SP three hyperze orbitals."}, {"title": "Sp Hybridization.txt", "text": "So, what is an SP hyperized orbital?"}, {"title": "Sp Hybridization.txt", "text": "Well, this is simply an orbital produced using 50% S orbitals and 50% P orbitals."}, {"title": "Sp Hybridization.txt", "text": "In other words, when we're combining our orbitals within that given atom, 50% comes from S and 50% comes from P. And this is known as an SP hyper dice orbital."}, {"title": "Sp Hybridization.txt", "text": "That's exactly what we have in this situation here."}, {"title": "Sp Hybridization.txt", "text": "So let's look at an example in nature."}, {"title": "Sp Hybridization.txt", "text": "So where is this evidence?"}, {"title": "Sp Hybridization.txt", "text": "So let's look at one particular example in which a Beryllium atom combines with two H atoms."}, {"title": "Sp Hybridization.txt", "text": "So let's examine the electron configuration of Beryllium."}, {"title": "Sp Hybridization.txt", "text": "So, Beryllium, in its neutral state, has four electrons, four protons, four neutrons."}, {"title": "Sp Hybridization.txt", "text": "So the electron configuration goes like this."}, {"title": "Sp Hybridization.txt", "text": "We have two electrons that go into our one S, and we have two electrons that go into the two S. Now, we also have the two p orbitals."}, {"title": "Sp Hybridization.txt", "text": "But since we have no more electrons, there are zero electrons in the two P orbital."}, {"title": "Sp Hybridization.txt", "text": "So we can either represent it this way, or we can simply remove the two P. Now, for my purposes, I'm going to leave it in this way, and we'll see why."}, {"title": "Sp Hybridization.txt", "text": "So my question is the following will this Be donate a two P orbital to bind with the H, or will it donate a hybrid orbital?"}, {"title": "Sp Hybridization.txt", "text": "In other words, which situation is more stable?"}, {"title": "Sp Hybridization.txt", "text": "So let's examine it this way."}, {"title": "Sp Hybridization.txt", "text": "Let's draw out our pictures."}, {"title": "Sp Hybridization.txt", "text": "Let's suppose that Be forms this hybridized orbital, and then this hybridized orbital interacts with the H atom to form our covalent bond."}, {"title": "Sp Hybridization.txt", "text": "And let's also suppose that we have a Beryllium atom that donates a simple two P orbital to interact with that H atom."}, {"title": "Sp Hybridization.txt", "text": "Let's see which one is more stable."}, {"title": "Sp Hybridization.txt", "text": "Well, recall that whenever bonds are formed, bonds or covalent bonds are formed by the overlap of atomic orbitals, as we see here."}, {"title": "Sp Hybridization.txt", "text": "And we know that the better the overlap, the larger the lobes, the more stable our compound is, the more stable our bond is."}, {"title": "Sp Hybridization.txt", "text": "So in which situation do we have a more stabilized overlap?"}, {"title": "Sp Hybridization.txt", "text": "A larger overlap?"}, {"title": "Sp Hybridization.txt", "text": "Well, clearly this case has a much bigger lobe."}, {"title": "Sp Hybridization.txt", "text": "And that means the interaction will be much better in this hybridized interaction."}, {"title": "Sp Hybridization.txt", "text": "In other words, this hybridized lobe creates a larger lobe."}, {"title": "Sp Hybridization.txt", "text": "And that means, because we have a larger lobe, we have a better overlap."}, {"title": "Sp Hybridization.txt", "text": "And so that means this is much more stable."}, {"title": "Sp Hybridization.txt", "text": "And so this will not occur."}, {"title": "Sp Hybridization.txt", "text": "We're going to have this type of bond."}, {"title": "Sp Hybridization.txt", "text": "In other words, within this benh, when Be bonds to H, it creates a hybridized orbital, which then bonds to the one S of the H. And let's see exactly that in this energy diagram."}, {"title": "Sp Hybridization.txt", "text": "So we can imagine this being the energy diagram."}, {"title": "Sp Hybridization.txt", "text": "So the higher up we go, the more energy we have."}, {"title": "Sp Hybridization.txt", "text": "The lower we go, the less energy we have."}, {"title": "Sp Hybridization.txt", "text": "What happens is the following."}, {"title": "Sp Hybridization.txt", "text": "The Beryllium creates this hybridized orbital SD hybridized which comes from one S and one P an St hybridized orbital."}, {"title": "Sp Hybridization.txt", "text": "And that orbital, which is a bit slightly higher in energy than our one S of the H atom."}, {"title": "Sp Hybridization.txt", "text": "So this is the H atom, and this is the one S orbital."}, {"title": "Sp Hybridization.txt", "text": "And this is the SP hybridized orbital of our Beryllium."}, {"title": "Sp Hybridization.txt", "text": "They will interact."}, {"title": "Sp Hybridization.txt", "text": "So we input two atomic orbitals, and we get two molecular orbitals."}, {"title": "Sp Hybridization.txt", "text": "So we get the one lower in energy and the one higher in energy."}, {"title": "Sp Hybridization.txt", "text": "So, once again, let's recap."}, {"title": "Sp Hybridization.txt", "text": "So hybridization is simply a process that occurs within an atom."}, {"title": "Sp Hybridization.txt", "text": "Within an atom, the orbitals can interact in a way to produce these hybridized orbitals that contain larger sections and smaller sections."}, {"title": "Sp Hybridization.txt", "text": "The largest sections are able to better interact with other orbitals found on other atoms as they produce better, more stable bonds."}, {"title": "Sp Hybridization.txt", "text": "Now, we've only spoken about SP hybridized orbitals in the next lecture we're going to look at the SP two and SP three hybridized orbitals."}, {"title": "Sp Hybridization.txt", "text": "You."}, {"title": "Mass percent example.txt", "text": "Mass percentage is simply another way of finding the concentration of the solution."}, {"title": "Mass percent example.txt", "text": "Mass percentage is equal to mass of some compound x divided by the total mass of the solution times 100."}, {"title": "Mass percent example.txt", "text": "The 100 gives you the percentage."}, {"title": "Mass percent example.txt", "text": "This is a fraction, so you divide mass by mass, so the units cancel out."}, {"title": "Mass percent example.txt", "text": "So mass percent is unitless."}, {"title": "Mass percent example.txt", "text": "Now let's do a problem with mass percentage."}, {"title": "Mass percent example.txt", "text": "The question tells us that we have 49 grams of gold, 25 grams of carbon, .5 water."}, {"title": "Mass percent example.txt", "text": "We need to find the mass percent of carbon, water and gold in our solution."}, {"title": "Mass percent example.txt", "text": "The first step is to find the mass percentage of gold."}, {"title": "Mass percent example.txt", "text": "To find the mass percentage of gold, we simply use the formula."}, {"title": "Mass percent example.txt", "text": "So 49 grams of gold divided by the total mass of the solution, 49 grams plus 25 grams plus now we can't add kilograms to grams."}, {"title": "Mass percent example.txt", "text": "So the first step is to convert this to grams."}, {"title": "Mass percent example.txt", "text": "We get plus 500 grams."}, {"title": "Mass percent example.txt", "text": "Now we multiply the whole thing by 100 to find the percentage, and we get 8.5%."}, {"title": "Mass percent example.txt", "text": "The mass perceptive of gold is 8.5."}, {"title": "Mass percent example.txt", "text": "To find the mass perceptive carbon, we follow the same exact formula."}, {"title": "Mass percent example.txt", "text": "25 grams of carbon divided by the total grams of the solution multiplied by 100 gives us 4.4%."}, {"title": "Mass percent example.txt", "text": "So the max percent of carbon is 4.4."}, {"title": "Mass percent example.txt", "text": "The last step could be done in two ways."}, {"title": "Mass percent example.txt", "text": "One way, you simply use the formula."}, {"title": "Mass percent example.txt", "text": "You plug things in, you find the result."}, {"title": "Mass percent example.txt", "text": "A quicker way would be simply to realize that if you add these guys up and subtracted from 100, we get the mass percent of the final thing final compound within our solution."}, {"title": "Mass percent example.txt", "text": "Namely water."}, {"title": "Mass percent example.txt", "text": "So 100 -8.5 plus 4.5 gives you 87."}, {"title": "Mass percent example.txt", "text": "1% the mass percent of water within our solution is 80 is 87.1%."}, {"title": "Second Law of Thermodynamics .txt", "text": "The second law of thermodynamics comes from the idea of the heat engine."}, {"title": "Second Law of Thermodynamics .txt", "text": "And what it basically says is that heat cannot be completely converted into work."}, {"title": "Second Law of Thermodynamics .txt", "text": "From the side ramp here of the heat engine, we can see that that's the case."}, {"title": "Second Law of Thermodynamics .txt", "text": "The energy that comes from the hot body, some of that energy goes into doing work, expanding the piston increase, increasing the volume."}, {"title": "Second Law of Thermodynamics .txt", "text": "And some of that goes into the cold body, decreasing the temperature as the piston moves back into its original position, thereby keeping the temperature constant."}, {"title": "Second Law of Thermodynamics .txt", "text": "Okay, we know by conservation of energy that the input energy equals the output energy."}, {"title": "Second Law of Thermodynamics .txt", "text": "That means QH, which means the energy input is equal to QC, the energy transferred into the cold body plus the work done by the system or by the molecules within the system."}, {"title": "Second Law of Thermodynamics .txt", "text": "And this directly correlates the first law of thermodynamics."}, {"title": "Second Law of Thermodynamics .txt", "text": "And in fact, it's the same thing."}, {"title": "Second Law of Thermodynamics .txt", "text": "It's basically this."}, {"title": "Second Law of Thermodynamics .txt", "text": "Okay, so we basically are saying that engines, heat engines aren't completely 100% efficient in converting heat into work."}, {"title": "Second Law of Thermodynamics .txt", "text": "So how efficient are they?"}, {"title": "Second Law of Thermodynamics .txt", "text": "Well, this formula here where E stands for efficiency or engine efficiency, can basically tell you how efficient an engine is."}, {"title": "Second Law of Thermodynamics .txt", "text": "If you know the temperature of the cold body and the temperature of the hot body, you can find the efficiency."}, {"title": "Second Law of Thermodynamics .txt", "text": "And this also shows you can see from algebra and basic calculus that ends, this becomes zero or tenths of zero."}, {"title": "Second Law of Thermodynamics .txt", "text": "That is, as TC decreases and Th increases or the difference between these two guys increases, the efficiency also increases."}, {"title": "Second Law of Thermodynamics .txt", "text": "Okay?"}, {"title": "Second Law of Thermodynamics .txt", "text": "You can pluck some values in and you'll see that as this becomes smaller and this becomes larger, that E becomes more efficient."}, {"title": "Second Law of Thermodynamics .txt", "text": "Okay, finally, let's talk about refrigerators and air conditioners."}, {"title": "Second Law of Thermodynamics .txt", "text": "So refrigerators and air conditioners are basically reverse heat engines."}, {"title": "Second Law of Thermodynamics .txt", "text": "What actually happens is work is inputted so that heat can be transferred from a cold body to a hot body or energy can be transferred from a cold body to a hot body."}, {"title": "Second Law of Thermodynamics .txt", "text": "This decreases the temperature of the system but increases the temperature of the outside."}, {"title": "Second Law of Thermodynamics .txt", "text": "For example, in this room in the summer, if I have an air conditioner and I plug it into the outlet, the energy that goes into the air conditioner basically does work on the inside room."}, {"title": "Second Law of Thermodynamics .txt", "text": "And what it does is it takes away energy from the inside room and throws the energy to the outside."}, {"title": "Second Law of Thermodynamics .txt", "text": "So what happens is the inside of the room is cooled, but the outside is heated or the temperature on the outside increases because on top of the work that's inputting, there is this QC that's input as well."}, {"title": "Second Law of Thermodynamics .txt", "text": "And this addition means that the outside temperature must increase."}, {"title": "Homo-Lumo interactions.txt", "text": "In this lecture, I'd like to examine the homoluma interaction between compounds."}, {"title": "Homo-Lumo interactions.txt", "text": "So let's look at the following example."}, {"title": "Homo-Lumo interactions.txt", "text": "Let's suppose we have compound one and alkane reacting with compound two, our hydrochloric acid."}, {"title": "Homo-Lumo interactions.txt", "text": "So this is a simple additional reaction."}, {"title": "Homo-Lumo interactions.txt", "text": "So in this reaction, this alkin actively lowers based base."}, {"title": "Homo-Lumo interactions.txt", "text": "This acts as a lewis acid."}, {"title": "Homo-Lumo interactions.txt", "text": "So this donates a pair of electrons."}, {"title": "Homo-Lumo interactions.txt", "text": "This accepts a pair of electrons."}, {"title": "Homo-Lumo interactions.txt", "text": "So our intermediate reactants are the intermediate carbocation that has a positive charge on this carbon and has an extra h that it got from the hydrochloric acid."}, {"title": "Homo-Lumo interactions.txt", "text": "Now, this chlorine, or chloride atom now has an extra pair of non bonding electrons, and so it develops a negative charge."}, {"title": "Homo-Lumo interactions.txt", "text": "In the second step of this addiction reaction, we have the chloride ion donating a pair of non bombing electrons."}, {"title": "Homo-Lumo interactions.txt", "text": "So this is our lewis base and our lewis acid."}, {"title": "Homo-Lumo interactions.txt", "text": "And so we form the following final product."}, {"title": "Homo-Lumo interactions.txt", "text": "So, let's examine this picture more closely using molecular and atomic orbitals."}, {"title": "Homo-Lumo interactions.txt", "text": "So let's draw our molecular orbitals or atomic orbitals for this reaction."}, {"title": "Homo-Lumo interactions.txt", "text": "So, here's our alkane."}, {"title": "Homo-Lumo interactions.txt", "text": "So our sigma bond and our pi bond, creating the double bond."}, {"title": "Homo-Lumo interactions.txt", "text": "What happens is this pair of electrons."}, {"title": "Homo-Lumo interactions.txt", "text": "So, this bond is composed of a pair of electrons, one electron in this two p orbital and the second electron in this two p orbital."}, {"title": "Homo-Lumo interactions.txt", "text": "So these two electrons attack this h atom, taking that h atom away from this chlorine atom."}, {"title": "Homo-Lumo interactions.txt", "text": "And we develop the following diagram."}, {"title": "Homo-Lumo interactions.txt", "text": "So, this is our intermediate cargo cation."}, {"title": "Homo-Lumo interactions.txt", "text": "So, this bond has been formed, this cobalt sigma ch bond."}, {"title": "Homo-Lumo interactions.txt", "text": "And now we have a positive charge on this twopie orbital because we have 1233 electrons."}, {"title": "Homo-Lumo interactions.txt", "text": "And that means we have a positive charge on the two p orbital."}, {"title": "Homo-Lumo interactions.txt", "text": "So, once again, this is SP two hybridized, and this is a planar molecule."}, {"title": "Homo-Lumo interactions.txt", "text": "So what happens next?"}, {"title": "Homo-Lumo interactions.txt", "text": "Well, next we have this lewis base."}, {"title": "Homo-Lumo interactions.txt", "text": "We have our chloride atom."}, {"title": "Homo-Lumo interactions.txt", "text": "And this non bonding pair of electrons attacks or attaches overlaps with this two p orbital, forming our spinal product."}, {"title": "Homo-Lumo interactions.txt", "text": "So, in the first step, this pi bond acted as a lewis base, donating this pair of electrons and this h atom on this compound on the hydrochloric acid active as a lewis acid, donating that h, donating that empty one s orbital."}, {"title": "Homo-Lumo interactions.txt", "text": "And likewise, here, this is the lewis acid because it has an empty two p orbital."}, {"title": "Homo-Lumo interactions.txt", "text": "And this is the lewis base because it has a pair of non bonding electrons."}, {"title": "Homo-Lumo interactions.txt", "text": "So, what exactly is a lewis athens based reaction?"}, {"title": "Homo-Lumo interactions.txt", "text": "So, a lewis athens based reaction is the interaction between a filled molecular orbital, as we saw here, and an antimolecular orbital."}, {"title": "Homo-Lumo interactions.txt", "text": "And this is known as a homolumo interaction."}, {"title": "Homo-Lumo interactions.txt", "text": "Homo simply meaning highest occupied molecular orbital, and lumo, meaning lowest unoccupied molecular orbital."}, {"title": "Homo-Lumo interactions.txt", "text": "So if we go back to the first step in this additional reaction, we see that our homo, the highest occupied molecular orbital, is the pi bond."}, {"title": "Homo-Lumo interactions.txt", "text": "So this is our lowest base."}, {"title": "Homo-Lumo interactions.txt", "text": "And in this case, our lowest unoccupied molecular orbital is the antibonding Sigma Bond."}, {"title": "Homo-Lumo interactions.txt", "text": "Remember, the bonding Sigma Bond is completely filled."}, {"title": "Homo-Lumo interactions.txt", "text": "The antibonding has no electrons, and so that means it must be the lowest unoccupied molecular orbital."}, {"title": "Homo-Lumo interactions.txt", "text": "Likewise, in this step, this was our lumo lowest unoccupied molecular orbital."}, {"title": "Homo-Lumo interactions.txt", "text": "And this was our homo, the Lewis base."}, {"title": "Homo-Lumo interactions.txt", "text": "So let's look at the second more closely in terms of energy."}, {"title": "Homo-Lumo interactions.txt", "text": "So, our homo is the lowest base."}, {"title": "Homo-Lumo interactions.txt", "text": "It's the highest occupied molecular orbital that has the non bonding pair of electrons."}, {"title": "Homo-Lumo interactions.txt", "text": "And this is our lumo lowest unoccupied molecular orbital."}, {"title": "Homo-Lumo interactions.txt", "text": "It's the two p orbital, and it's a bit higher in energy than our homo."}, {"title": "Homo-Lumo interactions.txt", "text": "So they interact."}, {"title": "Homo-Lumo interactions.txt", "text": "They overlap to form our molecular Sigma Bond."}, {"title": "Homo-Lumo interactions.txt", "text": "And the two electrons go into this bonding molecular orbital."}, {"title": "Homo-Lumo interactions.txt", "text": "And no electrons go into the antibinding molecular orbital because it's higher in energy."}, {"title": "Homo-Lumo interactions.txt", "text": "So, once again, as an overview, a Lewis acidbased reaction is simply a reaction between a filled orbital of one compound and an empty orbital of second compound."}, {"title": "Homo-Lumo interactions.txt", "text": "And this is actually a homoloomo interaction."}, {"title": "Electrolytic cells .txt", "text": "So far, we have spoken about three types of electrochemical cells, namely voltaic cells, concentration cells, and fuel cells."}, {"title": "Electrolytic cells .txt", "text": "Now, in this lecture, we're going to discuss a fourth type of electrochemical cell called an electrolytic cell."}, {"title": "Electrolytic cells .txt", "text": "Now, electrolytic cells are electrochemical cells that are supplied with an outside source of electrons, which allows reactant favorite redox reactions to occur."}, {"title": "Electrolytic cells .txt", "text": "Now, recall that voltaic cells convert chemical energy into electrical work via the process of moving electrons in a spontaneous product favorite reaction."}, {"title": "Electrolytic cells .txt", "text": "So, unlike voltaic cells, electrolytic cells do the opposite."}, {"title": "Electrolytic cells .txt", "text": "They use up electrical work to power reactant favorite non spontaneous reactions."}, {"title": "Electrolytic cells .txt", "text": "Now, let's look at an example."}, {"title": "Electrolytic cells .txt", "text": "Let's look at the decomposition of molten sodium chloride."}, {"title": "Electrolytic cells .txt", "text": "Now, what molten means is that it's heated to a certain temperature so that it goes from a solid state to a liquid state."}, {"title": "Electrolytic cells .txt", "text": "This is not an aqueous state."}, {"title": "Electrolytic cells .txt", "text": "It's a liquid state of sodium chloride, meaning these guys dissociate, but there is no water in our mixture."}, {"title": "Electrolytic cells .txt", "text": "There's no solvent."}, {"title": "Electrolytic cells .txt", "text": "So let's look at our electrolytic electrochemical cell."}, {"title": "Electrolytic cells .txt", "text": "So it's composed of not two half cells, but one half cell."}, {"title": "Electrolytic cells .txt", "text": "So one beaker."}, {"title": "Electrolytic cells .txt", "text": "Now, within this beaker, we have melted or liquid sodium chloride."}, {"title": "Electrolytic cells .txt", "text": "So we have a bunch of sodium molecules or sodium ions chloride ions."}, {"title": "Electrolytic cells .txt", "text": "So these two electrodes are in there, so they're made from the same exact material."}, {"title": "Electrolytic cells .txt", "text": "And what happens is we connect these guards to an outside power source, like a battery or a voltage cell."}, {"title": "Electrolytic cells .txt", "text": "Now, what happens is this battery powers."}, {"title": "Electrolytic cells .txt", "text": "It allows electrons to transfer in this direction."}, {"title": "Electrolytic cells .txt", "text": "So if they transfer this way, that means this metal obtains these electrons."}, {"title": "Electrolytic cells .txt", "text": "So this metal or electrode forms a negative charge, while this electrode forms a positive charge, because electrons will be taken away from this electrode."}, {"title": "Electrolytic cells .txt", "text": "So, since this develops a negative charge, let's see what happens with the portion that's immersed into our liquid."}, {"title": "Electrolytic cells .txt", "text": "Well, we said some of the sodium molecules will be moving around, and since they are positively charged, they will be attracted to this negatively charged electrode."}, {"title": "Electrolytic cells .txt", "text": "Likewise, these chloride atoms are negatively charged, so they will be attracted to this positively charged electrode."}, {"title": "Electrolytic cells .txt", "text": "So we'll have a separation of sodium and chloride in our liquid."}, {"title": "Electrolytic cells .txt", "text": "Now, what happens when our sodium positively charged ion hits this negatively charged electron?"}, {"title": "Electrolytic cells .txt", "text": "Well, some of the electrons will transfer into our sodium molecule, and that means our sodium will be reduced."}, {"title": "Electrolytic cells .txt", "text": "So this section is where reduction occurs."}, {"title": "Electrolytic cells .txt", "text": "And that means by definition, it must be our cathode."}, {"title": "Electrolytic cells .txt", "text": "Now, likewise, when these molecules or ions hit this little electrode, they give off some of these electrons, because electrons want to move from a negative charge to a positive charge."}, {"title": "Electrolytic cells .txt", "text": "So when this hits it, electrons travel inside this electrode, and they enter our circuit and travel all the way down here."}, {"title": "Electrolytic cells .txt", "text": "So what happens when electrons leave?"}, {"title": "Electrolytic cells .txt", "text": "Well, this guy is oxidized into diatomic gas, and so it evaporates into our environment."}, {"title": "Electrolytic cells .txt", "text": "And this is where oxidation takes place."}, {"title": "Electrolytic cells .txt", "text": "And so, by definition, this guy is our anode."}, {"title": "Electrolytic cells .txt", "text": "So notice two important differences between voltaic cells and electrolytic cells."}, {"title": "Electrolytic cells .txt", "text": "Our cathode in this situation is negative, and our anode is positive."}, {"title": "Electrolytic cells .txt", "text": "But in voltaic cells, it's reversed."}, {"title": "Electrolytic cells .txt", "text": "Our cathode is positive and our Amote is negative."}, {"title": "Electrolytic cells .txt", "text": "And that's because this electron doesn't travel this way like it does in voltaic cells, but it travels this way due to this outside battery source."}, {"title": "Electrolytic cells .txt", "text": "Another important difference, obviously, is the fact that in electrolytic cells, we have outside battery source."}, {"title": "Electrolytic cells .txt", "text": "We have an outside power source."}, {"title": "Electrolytic cells .txt", "text": "But in this will take cells."}, {"title": "Electrolytic cells .txt", "text": "We don't have it."}, {"title": "Electrolytic cells .txt", "text": "Now, so let's look at the oxidation reaction that occurs in our anode."}, {"title": "Electrolytic cells .txt", "text": "So two of these molecules, two of these ions give off those two electrons, forming our diatomic gas molecule, and the diatomic gas molecule evaporates into our environment."}, {"title": "Electrolytic cells .txt", "text": "Now, let's look at a reduction reaction."}, {"title": "Electrolytic cells .txt", "text": "This reduction reaction occurs in the following manner."}, {"title": "Electrolytic cells .txt", "text": "Two sodium ions react with two electrons."}, {"title": "Electrolytic cells .txt", "text": "When they hit this metal, they take up those two electrons, forming two sodium solid molecules or two moles of sodium solid molecules."}, {"title": "Electrolytic cells .txt", "text": "Now, our net reaction is just an addition of this guy to this guy."}, {"title": "Electrolytic cells .txt", "text": "Notice that electrons cancel, and we simply get the following net reduction reaction."}, {"title": "Electrolytic cells .txt", "text": "Now, if we were to look up the electron potentials or the cell potentials for this reaction and this reaction, we would get the following voltages."}, {"title": "Electrolytic cells .txt", "text": "Now, to find the net or the final cell voltage, we simply add these guys up, and we get negative 4.0\n72 volts."}, {"title": "Electrolytic cells .txt", "text": "So that means that this much voltage must be supplied to our electrolytic cell by this battery to power this reaction."}, {"title": "Electrolytic cells .txt", "text": "So decomposition of this guy required energy."}, {"title": "Electrolytic cells .txt", "text": "Now, other decomposition reactions are very popular."}, {"title": "Electrolytic cells .txt", "text": "For example, decomposition of water."}, {"title": "Electrolytic cells .txt", "text": "Now, in the next lecture, we're going to look at the decomposition of aqueous sodium chloride."}, {"title": "Electrolytic cells .txt", "text": "Now, that's a little bit different, and we'll see how."}, {"title": "Neuron Cells Part I .txt", "text": "Well, there are many different examples of concentration cells."}, {"title": "Neuron Cells Part I .txt", "text": "Today we're going to look at a very important biological example of a concentration cell called a neuron cell."}, {"title": "Neuron Cells Part I .txt", "text": "Now, neuron cells are simply specialized concentration cells found within our nervous system, within our body that communicate with one another via changes in ion concentration."}, {"title": "Neuron Cells Part I .txt", "text": "Now, these changes in ion concentration create a difference in voltage or something called a cell voltage."}, {"title": "Neuron Cells Part I .txt", "text": "And this difference in voltage creates electrical signals."}, {"title": "Neuron Cells Part I .txt", "text": "Now, these electrical signals travel from one cell to another, and this is how cells communicate."}, {"title": "Neuron Cells Part I .txt", "text": "Now let's look at something called a resting electrical potential resell."}, {"title": "Neuron Cells Part I .txt", "text": "Now, our cells within our body, specifically neuron cells, establish electrical potentials or cell voltages at rest."}, {"title": "Neuron Cells Part I .txt", "text": "And what this guy simply means, it's the cell voltage produced by our cell when no signals are being transducted or conducted from one cell to another."}, {"title": "Neuron Cells Part I .txt", "text": "Now let's look at a portion of our cell membrane found at the exxon hillock."}, {"title": "Neuron Cells Part I .txt", "text": "The exxon hillock is simply the portion of the neuron where our signal is generated."}, {"title": "Neuron Cells Part I .txt", "text": "But remember, we're talking about the resting potential."}, {"title": "Neuron Cells Part I .txt", "text": "That means no signals are being generated just yet."}, {"title": "Neuron Cells Part I .txt", "text": "So let's examine the different types of ions that are present within our body, within our cells."}, {"title": "Neuron Cells Part I .txt", "text": "So we see that we have calcium, we have potassium, we have sodium, and we have chloride."}, {"title": "Neuron Cells Part I .txt", "text": "Now, when we're at our resting potential, we have a lower concentration of calcium, sodium chloride inside the cell."}, {"title": "Neuron Cells Part I .txt", "text": "This is the inside than the outside."}, {"title": "Neuron Cells Part I .txt", "text": "On the contrary, we have a higher concentration of potassium ions on the inside than the outside."}, {"title": "Neuron Cells Part I .txt", "text": "Now notice we have a semipermandal membrane."}, {"title": "Neuron Cells Part I .txt", "text": "So we have hydrophilic heads and hydrophobic tails."}, {"title": "Neuron Cells Part I .txt", "text": "These guys are transport membranes or transport proteins."}, {"title": "Neuron Cells Part I .txt", "text": "And these proteins allow ions to flow in or as a cell, the active transport or passive transport."}, {"title": "Neuron Cells Part I .txt", "text": "Now, so today we're only going to look at this guy here, potassium ion."}, {"title": "Neuron Cells Part I .txt", "text": "But notice that our resting electrical potential, the cell or our cell voltage, is generated by simply adding up the cell voltages of all these four ions."}, {"title": "Neuron Cells Part I .txt", "text": "When we add all these guys up, we get our final cell voltage or the resting electrical potential."}, {"title": "Neuron Cells Part I .txt", "text": "Now, today, to save time, I'm only going to show you for this potassium ion."}, {"title": "Neuron Cells Part I .txt", "text": "You can do these on your own."}, {"title": "Neuron Cells Part I .txt", "text": "So let's take this potassium ion and let's create a concentration cell or a specialized concentration cell called a neuron cell."}, {"title": "Neuron Cells Part I .txt", "text": "So this is our electrochemical concentration cell for potassium."}, {"title": "Neuron Cells Part I .txt", "text": "This is our negatively charged anode and our positively charged cathode."}, {"title": "Neuron Cells Part I .txt", "text": "Now, this is where oxidation of potassium takes place."}, {"title": "Neuron Cells Part I .txt", "text": "And this is where reduction of potassium takes place."}, {"title": "Neuron Cells Part I .txt", "text": "You could think of this conductor, that electrodes and a sulfbridge, as representing the cell membrane."}, {"title": "Neuron Cells Part I .txt", "text": "And the solution on this in this anode is the outside solution and the cathode is the inside solution."}, {"title": "Neuron Cells Part I .txt", "text": "And that's because initially in a concentration cell, this guy is more dilute."}, {"title": "Neuron Cells Part I .txt", "text": "That means it's the outside, because remember, we have less potassium on the outside than on the inside."}, {"title": "Neuron Cells Part I .txt", "text": "So this guy must be the inside."}, {"title": "Neuron Cells Part I .txt", "text": "So now let's see what happens."}, {"title": "Neuron Cells Part I .txt", "text": "Well, electrons leave this potassium ion or leave the potassium solid ion this electrode and travel via the conductor, via the cell membrane onto this electrode."}, {"title": "Neuron Cells Part I .txt", "text": "At the same time, they release these potassium ions into our solution."}, {"title": "Neuron Cells Part I .txt", "text": "So the concentration of this guy on the outside becomes greater."}, {"title": "Neuron Cells Part I .txt", "text": "Likewise, these guys on the inside here are taken up because they react with the electrons to form our K solid."}, {"title": "Neuron Cells Part I .txt", "text": "And this changes the concentration of our inside and outside."}, {"title": "Neuron Cells Part I .txt", "text": "So this is our oxidation reaction, where our potassium is oxidized, and our reduction reaction, where the potassium accepts the electrons form of the solid."}, {"title": "Neuron Cells Part I .txt", "text": "Now, if we if we want to find the net rebus reaction, we simply add these two guys up the east cancel, the K solids cancel, and we are left with K plus inside and K plus outside."}, {"title": "Neuron Cells Part I .txt", "text": "Notice the reactants is the inside."}, {"title": "Neuron Cells Part I .txt", "text": "This is where we begin, and this guy is the outside."}, {"title": "Neuron Cells Part I .txt", "text": "This is where we end because electrons travel this way, but the ions want to travel this way because we have more ions on the outside on the inside than the outside."}, {"title": "Neuron Cells Part I .txt", "text": "So, once again, in the electrochemical cell setup, electrons travel this way, but C plus atoms travel this way because this concentration increases while this guy decreases."}, {"title": "Neuron Cells Part I .txt", "text": "Now, if we look up the cell voltage of this oxidation reaction and this reduction reaction, we find that they're the same magnitude but different signs."}, {"title": "Neuron Cells Part I .txt", "text": "So if we add them up, that means they will be zero."}, {"title": "Neuron Cells Part I .txt", "text": "And that's exactly what we have in any concentration cell."}, {"title": "Neuron Cells Part I .txt", "text": "And we'll see what that means in a second."}, {"title": "Calculating the equivalence point .txt", "text": "In this lecture, I will show you a way of finding the equivalence point of a buffer system."}, {"title": "Calculating the equivalence point .txt", "text": "Now, if you don't know what the equivalence point is, check out the link below."}, {"title": "Calculating the equivalence point .txt", "text": "So in the beginning, we have a buffer solution of some known asset."}, {"title": "Calculating the equivalence point .txt", "text": "So if we know the asset, that means we know the asset amortization constant."}, {"title": "Calculating the equivalence point .txt", "text": "We can simply look that up."}, {"title": "Calculating the equivalence point .txt", "text": "So in my first step, I basically want to find a KB."}, {"title": "Calculating the equivalence point .txt", "text": "And I want to find a KB using this formula here."}, {"title": "Calculating the equivalence point .txt", "text": "Now, if you don't know what this formula is or where it comes from, check out the link above and I'll tell you why in a second."}, {"title": "Calculating the equivalence point .txt", "text": "We want to find the KB."}, {"title": "Calculating the equivalence point .txt", "text": "Well, kw, something we know at some given temperature at a 25 degree celsius, kw is tens of negative 14."}, {"title": "Calculating the equivalence point .txt", "text": "It's the ionization constant of water."}, {"title": "Calculating the equivalence point .txt", "text": "Now, this guy equals ka, something we know times KB."}, {"title": "Calculating the equivalence point .txt", "text": "So we find KB by simply dividing kw by ka."}, {"title": "Calculating the equivalence point .txt", "text": "Now, why do we need the KB?"}, {"title": "Calculating the equivalence point .txt", "text": "Well, remember what the equivalent point is."}, {"title": "Calculating the equivalence point .txt", "text": "It's the point at which all the asset has been neutralized by some base, right?"}, {"title": "Calculating the equivalence point .txt", "text": "So I can use the KB to find the amount of base needed to neutralize our acid completely."}, {"title": "Calculating the equivalence point .txt", "text": "And then if I know my concentration of base, I could find the poh."}, {"title": "Calculating the equivalence point .txt", "text": "And using the poh, I can find the PH."}, {"title": "Calculating the equivalence point .txt", "text": "And that's exactly what we do."}, {"title": "Calculating the equivalence point .txt", "text": "So in my second step, I basically use the KB or the base annette and constant."}, {"title": "Calculating the equivalence point .txt", "text": "I equate that to my equilibrium expression, which states that the concentration of hydroxide, what I'm looking for, equals the concentration of the conjugate acid over the concentration of the conjugate base."}, {"title": "Calculating the equivalence point .txt", "text": "Now, I could get this guy in this side and divide by this guy and get the concentration that I'm looking at equals a known constant, unknown amount, and a known amount."}, {"title": "Calculating the equivalence point .txt", "text": "Now I solve and I find my concentration."}, {"title": "Calculating the equivalence point .txt", "text": "Next, I find my poh by using the formula which is negative lot of the concentration found here in step three."}, {"title": "Calculating the equivalence point .txt", "text": "And finally, in the final step, I solve for that PH by using the formula 14 equals poh plus PH."}, {"title": "Calculating the equivalence point .txt", "text": "Now, if you don't know where this formula comes from, check out the link right there."}, {"title": "Calculating the equivalence point .txt", "text": "So basically rearrange and find my PH."}, {"title": "Calculating the equivalence point .txt", "text": "Now, remember, the PH represents the equivalence point, right?"}, {"title": "Calculating the equivalence point .txt", "text": "It's the point at which all my asset has been completely neutralized by the base that I just found, the amount of base."}, {"title": "Calculating the equivalence point .txt", "text": "And that's how you find the equivalence point of a buffer solution."}, {"title": "The Cage Effect of Solvents .txt", "text": "On average, molecules found in the liquid state collide 100 times more frequently than the same molecules found in the gas state."}, {"title": "The Cage Effect of Solvents .txt", "text": "That means we should be able to assume that reactions occur quicker in the liquid state than in the gas state because reactions require collisions."}, {"title": "The Cage Effect of Solvents .txt", "text": "Now, this is not actually the case, and this is because of an effect called the effect of solvent molecules or Cage effect of solvent molecules."}, {"title": "The Cage Effect of Solvents .txt", "text": "Now let's look at the following reaction."}, {"title": "The Cage Effect of Solvents .txt", "text": "Suppose a red molecule must react with an orange molecule to produce a red orange product."}, {"title": "The Cage Effect of Solvents .txt", "text": "Now, suppose we dissolve these guys in a liquid."}, {"title": "The Cage Effect of Solvents .txt", "text": "So in liquid reactants are dissolved in a solvent, like, for example, water, which ends up predominating the solution."}, {"title": "The Cage Effect of Solvents .txt", "text": "Therefore, most of the collisions in liquids occur between solvent and solute."}, {"title": "The Cage Effect of Solvents .txt", "text": "And this means that even though the collisions occur more frequently in liquid than acoustic solutions, a lot of those collisions are between solvent and soluble molecules."}, {"title": "The Cage Effect of Solvents .txt", "text": "And the only way you react molecules is if the reactive molecules react."}, {"title": "The Cage Effect of Solvents .txt", "text": "So, because most of the collisions occur between solid molecules and solid molecules, that means, on average, reactions in the gas state and liquid state will be approximately the same."}, {"title": "The Cage Effect of Solvents .txt", "text": "Now let's look at this Cage effect."}, {"title": "The Cage Effect of Solvents .txt", "text": "Suppose we have our system where the red molecules are water solid molecules and the red and orange molecules or the molecules spoken about here, are the reactants."}, {"title": "The Cage Effect of Solvents .txt", "text": "So notice that the red molecule is in a cage of solid molecules and before it leaves, they make many collisions with the water cage."}, {"title": "The Cage Effect of Solvents .txt", "text": "Eventually, however, it will bounce out."}, {"title": "The Cage Effect of Solvents .txt", "text": "And if it bounces into another cage where this origin molecule is present, then it will react to former products."}, {"title": "The Cage Effect of Solvents .txt", "text": "But otherwise, if it jumps into another cage that doesn't have another reactor molecule, it will continue balancing."}, {"title": "The Cage Effect of Solvents .txt", "text": "And this greatly slows down our reaction in liquid and increased space."}, {"title": "The Cage Effect of Solvents .txt", "text": "And that's exactly why, at the end, even though on average, molecules in a liquid state make 100 times more collisions than molecules in a gas state, because of this Cage effect, the rates in a gas state and liquid state are about the same."}, {"title": "Carbon Dioxide vs Water Phase Diagrams .txt", "text": "Let's examine the two different phase diagrams for water and for carbon dioxide."}, {"title": "Carbon Dioxide vs Water Phase Diagrams .txt", "text": "First, notice that the y axis in both cases is pressure given ATMs."}, {"title": "Carbon Dioxide vs Water Phase Diagrams .txt", "text": "Second the X axis is temperature."}, {"title": "Carbon Dioxide vs Water Phase Diagrams .txt", "text": "Now two main differences exist between the two phase diagrams."}, {"title": "Carbon Dioxide vs Water Phase Diagrams .txt", "text": "First at one atmospheric pressure."}, {"title": "Carbon Dioxide vs Water Phase Diagrams .txt", "text": "Water exists in all three phases."}, {"title": "Carbon Dioxide vs Water Phase Diagrams .txt", "text": "However, for the carbon dioxide diagram, we see that carbon dioxide exists only in the solid phase and in the gas days."}, {"title": "Carbon Dioxide vs Water Phase Diagrams .txt", "text": "Let's look at the water diagram first."}, {"title": "Carbon Dioxide vs Water Phase Diagrams .txt", "text": "So at low temperatures, from here to here, we can find water in the solid state."}, {"title": "Carbon Dioxide vs Water Phase Diagrams .txt", "text": "At medium temperatures, from here to here, we can find water in the liquid state."}, {"title": "Carbon Dioxide vs Water Phase Diagrams .txt", "text": "And finally, at high temperatures above this temperature, we can find water in the gas state."}, {"title": "Carbon Dioxide vs Water Phase Diagrams .txt", "text": "For carbon dioxide."}, {"title": "Carbon Dioxide vs Water Phase Diagrams .txt", "text": "However, at one ATM, at low temperatures, below this temperature, we find that in the solid base and then we see that above this temperature, our solid sublons directly into the gas state."}, {"title": "Carbon Dioxide vs Water Phase Diagrams .txt", "text": "And so we could only find carbon dioxide in a solid and gas state at 180 m. The only way we could get into the liquid state is if we increase pressure and then increase temperature."}, {"title": "Carbon Dioxide vs Water Phase Diagrams .txt", "text": "The second main difference, and perhaps the more important difference, is the following."}, {"title": "Carbon Dioxide vs Water Phase Diagrams .txt", "text": "For the phase diagram of water."}, {"title": "Carbon Dioxide vs Water Phase Diagrams .txt", "text": "The boundary between the solid and the liquid line."}, {"title": "Carbon Dioxide vs Water Phase Diagrams .txt", "text": "This line has a negative slope."}, {"title": "Carbon Dioxide vs Water Phase Diagrams .txt", "text": "While for the carbon dioxide phase diagram, the boundary between the solid and liquid is positive."}, {"title": "Carbon Dioxide vs Water Phase Diagrams .txt", "text": "It has a positive slope."}, {"title": "Carbon Dioxide vs Water Phase Diagrams .txt", "text": "So it's increasing here."}, {"title": "Carbon Dioxide vs Water Phase Diagrams .txt", "text": "And it's decreasing here."}, {"title": "Carbon Dioxide vs Water Phase Diagrams .txt", "text": "And this happens because water has special properties."}, {"title": "Carbon Dioxide vs Water Phase Diagrams .txt", "text": "As a solid."}, {"title": "Carbon Dioxide vs Water Phase Diagrams .txt", "text": "The molecules in the solid states are very far apart or further apart than they are in the liquid water states."}, {"title": "Carbon Dioxide vs Water Phase Diagrams .txt", "text": "And that means liquid."}, {"title": "Carbon Dioxide vs Water Phase Diagrams .txt", "text": "The molecules are closer."}, {"title": "Carbon Dioxide vs Water Phase Diagrams .txt", "text": "So for some given volume water, liquid or liquid water is more dense than solid water."}, {"title": "Carbon Dioxide vs Water Phase Diagrams .txt", "text": "And that's why ice states a float."}, {"title": "Carbon Dioxide vs Water Phase Diagrams .txt", "text": "Because ice is less dense than water."}, {"title": "Carbon Dioxide vs Water Phase Diagrams .txt", "text": "So for this guy, however, the solid is more dense than the liquid, and therefore, this slope is positive."}, {"title": "Carbon Dioxide vs Water Phase Diagrams .txt", "text": "So if you place a solid carbon dioxide into the liquid, it's going to sink straight down."}, {"title": "Carbon Dioxide vs Water Phase Diagrams .txt", "text": "Now, one more effect because of this negative slope is the following Because the slope is negative."}, {"title": "Carbon Dioxide vs Water Phase Diagrams .txt", "text": "If we keep our temperature constant, say, somewhere right here."}, {"title": "Carbon Dioxide vs Water Phase Diagrams .txt", "text": "So if we keep this temperature constant, we see that we can actually make the solid become a liquid by simply increasing our pressure."}, {"title": "Carbon Dioxide vs Water Phase Diagrams .txt", "text": "So at constant temperature, we can make a solid become a liquid by simply compressing it, increasing the pressure."}, {"title": "Carbon Dioxide vs Water Phase Diagrams .txt", "text": "But for this situation, we can't."}, {"title": "Carbon Dioxide vs Water Phase Diagrams .txt", "text": "The only way we get a solid to become a liquid is if we increase temperature."}, {"title": "Carbon Dioxide vs Water Phase Diagrams .txt", "text": "Now, for the most part, most substances follow this phase than eye grab."}, {"title": "Carbon Dioxide vs Water Phase Diagrams .txt", "text": "Now, some substances such as water follow this phase that I grab."}, {"title": "Carbon Dioxide vs Water Phase Diagrams .txt", "text": "This is less common."}, {"title": "Phase Change of Water .txt", "text": "In this lecture, we're going to look at the phase change of water at constant pressure at one ATM when it goes from a very low temperature to a very high temperature."}, {"title": "Phase Change of Water .txt", "text": "So the Y axis is temperature in Celsius."}, {"title": "Phase Change of Water .txt", "text": "The X axis is energy input."}, {"title": "Phase Change of Water .txt", "text": "And Joules, let's begin at negative 60 Celsius."}, {"title": "Phase Change of Water .txt", "text": "So we want to go from negative negative 60 celsius to zero celsius."}, {"title": "Phase Change of Water .txt", "text": "And we do so by heating our system."}, {"title": "Phase Change of Water .txt", "text": "So what happens on a microscopic level when we heat the system?"}, {"title": "Phase Change of Water .txt", "text": "Well, on a microscopic level, we increase the kinetic energy of our molecules because kinetic energy is what's responsible for increasing temperature."}, {"title": "Phase Change of Water .txt", "text": "So our potential energy stays the same from this point to this point."}, {"title": "Phase Change of Water .txt", "text": "But our kinetic energy increases."}, {"title": "Phase Change of Water .txt", "text": "Now, when we get to zero degrees Celsius, a phase change occurs."}, {"title": "Phase Change of Water .txt", "text": "So solid becomes a liquid and the change in temperature notice is zero."}, {"title": "Phase Change of Water .txt", "text": "So the slope is zero."}, {"title": "Phase Change of Water .txt", "text": "So from this point to this point, the temperature is the same."}, {"title": "Phase Change of Water .txt", "text": "It's zero degrees Celsius."}, {"title": "Phase Change of Water .txt", "text": "And that's because all the energy input goes into increasing potential energy of our substance."}, {"title": "Phase Change of Water .txt", "text": "And potential energy increase is what causes the change in phase."}, {"title": "Phase Change of Water .txt", "text": "When we finish the phase change, we want to increase temperature once again."}, {"title": "Phase Change of Water .txt", "text": "So once again, all the energy input goes into increasing our kinetic energy of our molecules."}, {"title": "Phase Change of Water .txt", "text": "Because kinetic energy is what's responsible for increasing temperature."}, {"title": "Phase Change of Water .txt", "text": "So when we get to 100 degrees Celsius, once again, our slope is zero."}, {"title": "Phase Change of Water .txt", "text": "That means our temperature change is zero."}, {"title": "Phase Change of Water .txt", "text": "All the energy goes into increasing potential energy of our bonds found within the liquid and gas phase."}, {"title": "Phase Change of Water .txt", "text": "So eventually all the liquid becomes gas."}, {"title": "Phase Change of Water .txt", "text": "And once again, we follow a linear graph here."}, {"title": "Phase Change of Water .txt", "text": "So any increase in energy will increase kinetic energy of our molecules."}, {"title": "Phase Change of Water .txt", "text": "So, once again, let's review."}, {"title": "Phase Change of Water .txt", "text": "So when the slope is zero, we deal with phase changes."}, {"title": "Phase Change of Water .txt", "text": "And here all energy input goes into increasing potential energy of the system."}, {"title": "Phase Change of Water .txt", "text": "No change in kinetic energy is observed."}, {"title": "Phase Change of Water .txt", "text": "And so the change in temperature in both cases is zero."}, {"title": "Phase Change of Water .txt", "text": "When we talk about going from this guy to this guy or from this guy to this guy, the intermediate phases between the phase changes, we talk about energy input that goes into increasing kinetic energy of the system because kinetic energy of the system is what increases temperature."}, {"title": "Phase Change of Water .txt", "text": "Because we want to go from zero to 100 and from negative 60 to zero."}, {"title": "Phase Change of Water .txt", "text": "We want to increase temperature and not the potential energy of the system."}, {"title": "Phase Change of Water .txt", "text": "So let's talk about one last thing."}, {"title": "Phase Change of Water .txt", "text": "So when we go from solid to liquid, that's called melting."}, {"title": "Phase Change of Water .txt", "text": "Okay?"}, {"title": "Phase Change of Water .txt", "text": "And melting according to this graph is endothermic."}, {"title": "Phase Change of Water .txt", "text": "And that's because our final energy level is somewhere here."}, {"title": "Phase Change of Water .txt", "text": "Our initial energy level is somewhere here."}, {"title": "Phase Change of Water .txt", "text": "So a larger amount of energy minus a smaller amount of energy gives us a positive number."}, {"title": "Phase Change of Water .txt", "text": "So the change in enthalpy of fusion is positive."}, {"title": "Phase Change of Water .txt", "text": "Melting is endothermic."}, {"title": "Phase Change of Water .txt", "text": "Likewise, going backward or freezing is exothermic because we're taking this number and we're subtracting this number from this number."}, {"title": "Phase Change of Water .txt", "text": "A smaller number minus a larger number gives you a negative number, and that means freezing."}, {"title": "Phase Change of Water .txt", "text": "Going this way is exothermic."}, {"title": "Phase Change of Water .txt", "text": "And so it releases energy into the environment, heating the environment and cooling our system."}, {"title": "Phase Change of Water .txt", "text": "So let's look at vaporization."}, {"title": "Phase Change of Water .txt", "text": "Vaporization is the process by which liquid molecules go into the gas state."}, {"title": "Phase Change of Water .txt", "text": "So it's going from here to here."}, {"title": "Phase Change of Water .txt", "text": "Once again, just like the change in enthalpy of fusion, change in enthalpy of vaporization is also positive."}, {"title": "Phase Change of Water .txt", "text": "It's endothermic because we take a large number and we subtract a small number from the large number and we get a positive number."}, {"title": "Phase Change of Water .txt", "text": "And once again, going from this stage to this stage, or from a gas to a liquid, which is called condensation, well, that's exothermic."}, {"title": "Phase Change of Water .txt", "text": "That's negative, because we take this number, subtracted from this number, and we get a negative number."}, {"title": "Phase Change of Water .txt", "text": "So vaporization and freezing is exothermic while melting, and vaporization is exothermic."}, {"title": "Acid Ionization Constant .txt", "text": "In this lecture we're going to talk about the ionization constants of acids known as KAS."}, {"title": "Acid Ionization Constant .txt", "text": "But before we talk about KAS, let's look at the ionization reaction of water."}, {"title": "Acid Ionization Constant .txt", "text": "Remember, water molecules can act as both acids and bases."}, {"title": "Acid Ionization Constant .txt", "text": "And in fact, if you add two water molecules together, one will act as an acid and the second one will act as a base, creating a conjugate acid and a conjugate base."}, {"title": "Acid Ionization Constant .txt", "text": "In other words, if this is our acid, it will donate the H, creating an oh ion."}, {"title": "Acid Ionization Constant .txt", "text": "And if this is our base, it will accept that H creating a hydronium ion."}, {"title": "Acid Ionization Constant .txt", "text": "So now, if we wanted to, we can also write the equilibrium equation for this reaction."}, {"title": "Acid Ionization Constant .txt", "text": "In other words, kw, our ionization constant for water is equal to hydronium concentration times the hydroxide concentration."}, {"title": "Acid Ionization Constant .txt", "text": "And at 25 degrees Celsius, this equals 10 times ten to negative 14."}, {"title": "Acid Ionization Constant .txt", "text": "Now, this process is called the autoimilization reaction."}, {"title": "Acid Ionization Constant .txt", "text": "And if you want to learn more about this reaction, check out the link below."}, {"title": "Acid Ionization Constant .txt", "text": "Now, in the same way that we talk about ionization constants of water, we can also talk about ionization constants of acids."}, {"title": "Acid Ionization Constant .txt", "text": "Except now they're not Kw, they're ka, where A is for our acid."}, {"title": "Acid Ionization Constant .txt", "text": "So let's suppose we have a hypothetical acid Ha reacting with a water molecule in a liquid state."}, {"title": "Acid Ionization Constant .txt", "text": "Now, what will happen?"}, {"title": "Acid Ionization Constant .txt", "text": "Well, this acid will donate the H, releasing the H, while the base will accept that age, creating a hydronium ion and a conjugate base."}, {"title": "Acid Ionization Constant .txt", "text": "So this is our conjugate acid, our conjugate base and our conjugate base and our conjugate acid."}, {"title": "Acid Ionization Constant .txt", "text": "Now, let's write the equilibrium constant stress in the same way we did for water for this acid."}, {"title": "Acid Ionization Constant .txt", "text": "So ka, our acid annetzation constant is equal to our concentration of our hydronium times, the concentration of the conjugate base."}, {"title": "Acid Ionization Constant .txt", "text": "Now, in this case, our conjugate base is simply this guy here."}, {"title": "Acid Ionization Constant .txt", "text": "Now, both guys are included in our numerator because both guys are in aqueous form."}, {"title": "Acid Ionization Constant .txt", "text": "Remember, liquids and solids are not included."}, {"title": "Acid Ionization Constant .txt", "text": "And that's why we didn't include these two water molecules."}, {"title": "Acid Ionization Constant .txt", "text": "Now, on the bottom, since we have an Ha in the Aqueous state, our conjugate acid, we must include the conjugate acid as well."}, {"title": "Acid Ionization Constant .txt", "text": "So Ha gets incorporated into our equilibrium constant expression."}, {"title": "Acid Ionization Constant .txt", "text": "Now, what is a k value or Ka value?"}, {"title": "Acid Ionization Constant .txt", "text": "Well, the ionization constant is simply a ratio from a mathematical perspective."}, {"title": "Acid Ionization Constant .txt", "text": "And what the Ka is, it's the amount of product formed over the amount of reactants left over."}, {"title": "Acid Ionization Constant .txt", "text": "So if this number is very large, then that means a lot of product was formed and very little reactants left over."}, {"title": "Acid Ionization Constant .txt", "text": "So what does that tell us about the Ha?"}, {"title": "Acid Ionization Constant .txt", "text": "Well, if this reaction is favored this way, if a lot of product is formed and very little reactor is left over, that means this acid is very good at giving off that age."}, {"title": "Acid Ionization Constant .txt", "text": "So it must be a very good acid by definition of an acid."}, {"title": "Acid Ionization Constant .txt", "text": "So that means if our Ka is large, we have a good acid."}, {"title": "Acid Ionization Constant .txt", "text": "Likewise, if our Ka is small, that means very little product is formed and a lot of reactors left over."}, {"title": "Acid Ionization Constant .txt", "text": "That means this asset is very bad at releasing that age, so it's a bad asset."}, {"title": "Acid Ionization Constant .txt", "text": "Now, we can deduce that if the Ka is greater than one, then that means it's a strong acid."}, {"title": "Acid Ionization Constant .txt", "text": "And if the Ka is less than one, that means it's a weak acid."}, {"title": "Acid Ionization Constant .txt", "text": "Now let's look at one more thing."}, {"title": "Acid Ionization Constant .txt", "text": "So what happens if our Ka is less than one?"}, {"title": "Acid Ionization Constant .txt", "text": "Then this guy must be a weak acid."}, {"title": "Acid Ionization Constant .txt", "text": "But that means our conjugate base must be a good base."}, {"title": "Acid Ionization Constant .txt", "text": "Likewise, if this was a good acid and our Ka was above one, that means this was a bad conjugate base."}, {"title": "Acid Ionization Constant .txt", "text": "Now let's look at a few examples."}, {"title": "Acid Ionization Constant .txt", "text": "Nitric acid in aqueous state could act with water to produce hydronium ion plus nitrate ion."}, {"title": "Acid Ionization Constant .txt", "text": "Now, the ka for this reaction for this acid is 20."}, {"title": "Acid Ionization Constant .txt", "text": "And that means, according to this theory, it's a very good acid."}, {"title": "Acid Ionization Constant .txt", "text": "And indeed it is."}, {"title": "Acid Ionization Constant .txt", "text": "Now let's look at hydrofluoric acid."}, {"title": "Acid Ionization Constant .txt", "text": "So hydrofluoric acid in the equated states react with water in the liquid state to produce hydronium plus the fion."}, {"title": "Acid Ionization Constant .txt", "text": "Now, the Ka for this reaction for this particular acid is very low."}, {"title": "Acid Ionization Constant .txt", "text": "It's 7.2 times ten to negative four."}, {"title": "Acid Ionization Constant .txt", "text": "And that means, according to this theory, it's a bad acid."}, {"title": "Acid Ionization Constant .txt", "text": "And in fact, it is a bad acid."}, {"title": "Acid Ionization Constant .txt", "text": "It's a weak acid."}, {"title": "Acid Ionization Constant .txt", "text": "So now we can use this ka value to determine whether or not an acid is a good acid or a bad asset."}, {"title": "Acid Ionization Constant .txt", "text": "Now, before we have to look at the polarity of the bond, we have to look at the bond strength and we have to look at the conjugate base."}, {"title": "Acid Ionization Constant .txt", "text": "Now, these values are still important, but now we have a fourth component."}, {"title": "Acid Ionization Constant .txt", "text": "We can use the ka value to determine if an acid is a good acid or a bad acid."}, {"title": "Ion Pairing .txt", "text": "In this lecture, I'm going to really quickly talk about a concept called ion pairing."}, {"title": "Ion Pairing .txt", "text": "Now, ion Pairing is A Momentary aggregation of Electrically charged ions found In A Concentrated solution Of Two Or More compounds."}, {"title": "Ion Pairing .txt", "text": "Now to really grasp what we mean by Ion pairing, let's create a solution and see what happens with the natural solution."}, {"title": "Ion Pairing .txt", "text": "So let's mix liquid water and solid sodium chloride and see what happens."}, {"title": "Ion Pairing .txt", "text": "Well, once we mix them, the sodium chloride dissociates and forms ions."}, {"title": "Ion Pairing .txt", "text": "So we have a bunch of polar water molecules separated by ions."}, {"title": "Ion Pairing .txt", "text": "At any given time, two of these ions might be separated by a solvent water molecule, and at this point, they can't interact with one another because of this separation."}, {"title": "Ion Pairing .txt", "text": "However, at another place, the solid molecule, the water molecule, might not separate them."}, {"title": "Ion Pairing .txt", "text": "And at this point, because of their proximity, the ions will form an ion pair."}, {"title": "Ion Pairing .txt", "text": "And this is only for the moment."}, {"title": "Ion Pairing .txt", "text": "Imagine two ions floating or flying around in the liquid, right?"}, {"title": "Ion Pairing .txt", "text": "Eventually they will get close to each other."}, {"title": "Ion Pairing .txt", "text": "And when they get close to each other, they will form that momentary bond."}, {"title": "Ion Pairing .txt", "text": "But it's only for the moment."}, {"title": "Ion Pairing .txt", "text": "Because if they're traveling, they will attract and will continue to travel."}, {"title": "Ion Pairing .txt", "text": "So eventually they will break."}, {"title": "Ion Pairing .txt", "text": "So they travel, attract and break."}, {"title": "Ion Pairing .txt", "text": "And it's only for the moment."}, {"title": "Ion Pairing .txt", "text": "And that's the difference between an Ion pair and an ionic bond."}, {"title": "Ion Pairing .txt", "text": "An ionic bond is not for the moment."}, {"title": "Ion Pairing .txt", "text": "It Stays."}, {"title": "Ion Pairing .txt", "text": "It Exists."}, {"title": "Ion Pairing .txt", "text": "If this sodium chloride is left untouched, it will continue."}, {"title": "Ion Pairing .txt", "text": "The ionic bond will continue to exist."}, {"title": "Ion Pairing .txt", "text": "But in this case, the Ion pair only exists for a moment."}, {"title": "Ion Pairing .txt", "text": "Now Ion Pairing does not exist in an ideal solution."}, {"title": "Ion Pairing .txt", "text": "And that's because in an ideal solution, by definition, all the ions are separated from one another by solvent molecules."}, {"title": "Ion Pairing .txt", "text": "So no attraction between two ions exists."}, {"title": "Ion Pairing .txt", "text": "So Ion pairing only exists in nonideal conditions."}, {"title": "Ion Pairing .txt", "text": "Now, if you want to see why Ion Pairing is important and where it's applied, check out the video below."}, {"title": "Ion Pairing .txt", "text": "In that video, I talk about something called boiling point elevation and melting point depression."}, {"title": "Ion Pairing .txt", "text": "And in this situation, something called BONHA factor experiences ion Pairing And because of ion pairing, the value of the Bonhot factor decreases."}, {"title": "Introduction to Gibbs Free Energy .txt", "text": "In this lecture, I will give an introduction to Gibbs free energy."}, {"title": "Introduction to Gibbs Free Energy .txt", "text": "So what is Gibbs free energy?"}, {"title": "Introduction to Gibbs Free Energy .txt", "text": "Well, Gibbs free energy, just like enthalpy, is a manmade concept, which means it cannot be measured."}, {"title": "Introduction to Gibbs Free Energy .txt", "text": "So you cannot use an instrument to measure Gibbs free energy of some object."}, {"title": "Introduction to Gibbs Free Energy .txt", "text": "Gibbs free energy could only measure expansion fundamentally."}, {"title": "Introduction to Gibbs Free Energy .txt", "text": "Now, that's because Gibbs free energy is defined by a formula."}, {"title": "Introduction to Gibbs Free Energy .txt", "text": "And this formula only holds under certain conditions."}, {"title": "Introduction to Gibbs Free Energy .txt", "text": "If these conditions aren't met, Gibbs free energy breaks down."}, {"title": "Introduction to Gibbs Free Energy .txt", "text": "Now, let's look at these conditions."}, {"title": "Introduction to Gibbs Free Energy .txt", "text": "These conditions are constant temperature and pressure."}, {"title": "Introduction to Gibbs Free Energy .txt", "text": "The reaction must be reversible, and there is no mechanical work done."}, {"title": "Introduction to Gibbs Free Energy .txt", "text": "Only TV work is allowed to be done."}, {"title": "Introduction to Gibbs Free Energy .txt", "text": "Now, let's see the result of constant temperature and pressure."}, {"title": "Introduction to Gibbs Free Energy .txt", "text": "In an isolated system, the number of moles stays the same."}, {"title": "Introduction to Gibbs Free Energy .txt", "text": "And that's because there is no exchange in mass."}, {"title": "Introduction to Gibbs Free Energy .txt", "text": "So, if the number of moles stay the same, if the temperature is constant and pressure is constant, and according to the ideal gas law, the volume remains constant, so there is no volume change."}, {"title": "Introduction to Gibbs Free Energy .txt", "text": "So, according to the formula for change in enthalpy, if there's no volume change, then this guy, the PV work done, is zero."}, {"title": "Introduction to Gibbs Free Energy .txt", "text": "And so we can approximate the change in enthalpy to simply equaling change in internal energy or change in energy or heat."}, {"title": "Introduction to Gibbs Free Energy .txt", "text": "Now, before we jump into the formula, let's look at entropy and entropy."}, {"title": "Introduction to Gibbs Free Energy .txt", "text": "So what is entropy?"}, {"title": "Introduction to Gibbs Free Energy .txt", "text": "Well, entropy tells us if the reaction is exothermic or endothermic."}, {"title": "Introduction to Gibbs Free Energy .txt", "text": "It does not tell us if the reaction is spontaneous."}, {"title": "Introduction to Gibbs Free Energy .txt", "text": "Okay?"}, {"title": "Introduction to Gibbs Free Energy .txt", "text": "That's important."}, {"title": "Introduction to Gibbs Free Energy .txt", "text": "Now let's look at entropy."}, {"title": "Introduction to Gibbs Free Energy .txt", "text": "Now, from another video, we learned that entropy is nature's tendency to create the most probable system, okay?"}, {"title": "Introduction to Gibbs Free Energy .txt", "text": "So, for example, if we have this isolated system, we have four molecules on this side."}, {"title": "Introduction to Gibbs Free Energy .txt", "text": "Entropy, by definition, will tell us that two of the molecules will want to go here and will want to create this system here."}, {"title": "Introduction to Gibbs Free Energy .txt", "text": "In other words, this system is more probable."}, {"title": "Introduction to Gibbs Free Energy .txt", "text": "Okay?"}, {"title": "Introduction to Gibbs Free Energy .txt", "text": "So we see that entropy and not enthalpy tells us if the reaction is spontaneous."}, {"title": "Introduction to Gibbs Free Energy .txt", "text": "Therefore, entropy determines spontaneity and not enthalpy."}, {"title": "Introduction to Gibbs Free Energy .txt", "text": "Okay?"}, {"title": "Introduction to Gibbs Free Energy .txt", "text": "Now let's look at Gibbs free energy."}, {"title": "Introduction to Gibbs Free Energy .txt", "text": "So, gifts free energy combines entropy and enthalpy the same way that enthalpy combines internal energy and change in volume."}, {"title": "Introduction to Gibbs Free Energy .txt", "text": "The formula for Gibbs free energy is as follows."}, {"title": "Introduction to Gibbs Free Energy .txt", "text": "The change in Gibbs free energy is equal to the change in entropy minus temperature times change in entropy."}, {"title": "Introduction to Gibbs Free Energy .txt", "text": "Now, when the change in Gibbs free energy is zero, the reaction is said to be at equilibrium."}, {"title": "Introduction to Gibbs Free Energy .txt", "text": "Okay?"}, {"title": "Introduction to Gibbs Free Energy .txt", "text": "The rate of the full reaction is the same as the rate of the reverse reaction."}, {"title": "Introduction to Gibbs Free Energy .txt", "text": "Now, when GIBS free energy is negative, the reaction is said to be spontaneous."}, {"title": "Introduction to Gibbs Free Energy .txt", "text": "If it's positive, it's said to be non spontaneous or non spontaneous."}, {"title": "Introduction to Gibbs Free Energy .txt", "text": "Okay?"}, {"title": "Introduction to Gibbs Free Energy .txt", "text": "Now, what git speed energy basically tells us is that even an exothermic reaction can be non spontaneous if this portion, if the change in entropy is negative, enough."}, {"title": "Introduction to Gibbs Free Energy .txt", "text": "And what?"}, {"title": "Introduction to Gibbs Free Energy .txt", "text": "It also tells us that an endothermic reaction could be spontaneous if this guy if the increase in entropy is large enough."}, {"title": "Introduction to Gibbs Free Energy .txt", "text": "So what gifts the energy tells us is that Spontaneity is determined solely by entropy."}, {"title": "Half Reactions .txt", "text": "So recall that redox reactions are chemical reactions that involve the transfer of electrons from one atom to another atom."}, {"title": "Half Reactions .txt", "text": "Now, this means one atom is oxidized and one atom is reduced."}, {"title": "Half Reactions .txt", "text": "So that means any redox reaction can be broken down into two types of reactions an oxidation reactions, in which an atom loses electrons and a reduction reaction, in which atoms gain electrons."}, {"title": "Half Reactions .txt", "text": "So let's look at a very simple redox reaction."}, {"title": "Half Reactions .txt", "text": "So, zinc metal reacts with aqueous copper to produce aqueous zinc and metal copper."}, {"title": "Half Reactions .txt", "text": "So let's break this reaction into an oxidation and a reduction reaction."}, {"title": "Half Reactions .txt", "text": "So, what gets oxidized?"}, {"title": "Half Reactions .txt", "text": "Well, our zinc solid goes from a neutral charge to a plus two charge."}, {"title": "Half Reactions .txt", "text": "That means our zinc loses two electrons."}, {"title": "Half Reactions .txt", "text": "So let's write the equation for that."}, {"title": "Half Reactions .txt", "text": "So, let's write the oxidation equation."}, {"title": "Half Reactions .txt", "text": "So, zinc solid becomes zinc plus two because it loses two electrons."}, {"title": "Half Reactions .txt", "text": "So our oxidation reaction involves the loss of electrons."}, {"title": "Half Reactions .txt", "text": "Now let's write the reduction reaction."}, {"title": "Half Reactions .txt", "text": "In our reduction reaction, our copper gets reduced because it gains those two electrons that are lost by the zinc."}, {"title": "Half Reactions .txt", "text": "So our copper plus two gains two electrons plus two electrons producing a neutral copper solid molecule."}, {"title": "Half Reactions .txt", "text": "So this is our oxidation and this is our reduction reactions."}, {"title": "Half Reactions .txt", "text": "Now, these two reactions are each called the half reaction."}, {"title": "Half Reactions .txt", "text": "And the half reaction is simply a way for us to visualize more clearly the transfer of electrons from one atom to another."}, {"title": "Half Reactions .txt", "text": "Because notice in this net reaction, there was no transfer of electrons."}, {"title": "Half Reactions .txt", "text": "We couldn't visualize the transfer electrons."}, {"title": "Half Reactions .txt", "text": "But in these half reactions, we have the plus two E and plus two e.\nSo this is simply a better way for us to see the movement of electrons."}, {"title": "Half Reactions .txt", "text": "Now, to go back to our net reaction net reduce reaction."}, {"title": "Half Reactions .txt", "text": "What we simply do is we add up the two half reactions."}, {"title": "Half Reactions .txt", "text": "So we add up the two half reactions by first adding up all the molecules on this side and then add up all the molecules on this side."}, {"title": "Half Reactions .txt", "text": "So zinc solid plus acreage copper plus two electrons gives us this produces everything on this side."}, {"title": "Half Reactions .txt", "text": "So zinc or acreage zinc plus copper solid plus our two electrons."}, {"title": "Half Reactions .txt", "text": "Now, notice one thing."}, {"title": "Half Reactions .txt", "text": "That two electrons up here on this side and on this side."}, {"title": "Half Reactions .txt", "text": "And that means by using simple algebra we just cross these guys out, we subtract two e, and what we get is our final net reaction."}, {"title": "Half Reactions .txt", "text": "So that means no electrons appear in the net reaction ever."}, {"title": "Half Reactions .txt", "text": "And that's because the number of electrons released by our oxidation reaction is equal to the number gained by our reduction reaction."}, {"title": "Half Reactions .txt", "text": "So whatever is gained must be lost somewhere."}, {"title": "Half Reactions .txt", "text": "And that's the conservation of energy."}, {"title": "Freezing Point depression Example .txt", "text": "In this example, I'm going to show you a very common way of finding the mobile mass of some unknown compound using the freezing point depression formula."}, {"title": "Freezing Point depression Example .txt", "text": "So in this example, we're given 2 grams of an unknown compound and we're given 100 grams of some solvent cyclohexane."}, {"title": "Freezing Point depression Example .txt", "text": "Now, our initial freezing point is six degrees Celsius."}, {"title": "Freezing Point depression Example .txt", "text": "Our final freezing point is 2.7 degrees Celsius."}, {"title": "Freezing Point depression Example .txt", "text": "Our constant for freezing is 20 Celsius times kilograms per mole."}, {"title": "Freezing Point depression Example .txt", "text": "Now, so we basically start with 100 grams of cyclohexane which freezes at six degrees Celsius."}, {"title": "Freezing Point depression Example .txt", "text": "We add 2 grams of unknown compound to our beaker of 100 grams of cyclohexane and that solution freezing point drops to 2.7 degrees Celsius."}, {"title": "Freezing Point depression Example .txt", "text": "Now, our goal is to use the freezing point depression formula to find the Molar mass."}, {"title": "Freezing Point depression Example .txt", "text": "In the first step we write our freezing depression formula and that basically state that's the change in temperature equal there constant times molarity times I I is a bond half factor and in this case it's one."}, {"title": "Freezing Point depression Example .txt", "text": "Because our unknown compound does not associate into anything, it stays the way it is."}, {"title": "Freezing Point depression Example .txt", "text": "So you plug in our values and we get six -20 or 2.7 degrees Celsius."}, {"title": "Freezing Point depression Example .txt", "text": "Divided by 20 our constant Celsius cancels moles goes on top and we get 0.165\nmoles per kilogram."}, {"title": "Freezing Point depression Example .txt", "text": "And this is our Molarity."}, {"title": "Freezing Point depression Example .txt", "text": "Now, in the second step, let's look at the formula for molality."}, {"title": "Freezing Point depression Example .txt", "text": "Molarity equals moles of compound divided by a kilogram of solids."}, {"title": "Freezing Point depression Example .txt", "text": "Now we're given kilogram of solids, so we know that we also know molality."}, {"title": "Freezing Point depression Example .txt", "text": "Now let's change our moles of compound formula to something else."}, {"title": "Freezing Point depression Example .txt", "text": "Let's see, how else can we represent the moles of compound?"}, {"title": "Freezing Point depression Example .txt", "text": "Now, whenever you want to find the moles of compound, we basically take our amount in grams divided by the molecular weight of that same compound and we get our moles."}, {"title": "Freezing Point depression Example .txt", "text": "So another way of finding or representing moles of compound is simply grams of compound divided by molecular weight."}, {"title": "Freezing Point depression Example .txt", "text": "But molecular weight and molar mass mean the same thing."}, {"title": "Freezing Point depression Example .txt", "text": "So we simply write molar mass and now we have this, we have Molarity and all we need is to find the Molar mass."}, {"title": "Freezing Point depression Example .txt", "text": "Remember, the grams of compound was given initially 2 grams of unknown compound and we can check using our units that this makes sense, grams divided by grams per mole."}, {"title": "Freezing Point depression Example .txt", "text": "The grams cancel moles goes on top and we're left with moles per kilogram."}, {"title": "Freezing Point depression Example .txt", "text": "And that's exactly what molality is."}, {"title": "Freezing Point depression Example .txt", "text": "Now, our third step."}, {"title": "Freezing Point depression Example .txt", "text": "In our last step, we basically plug in our values."}, {"title": "Freezing Point depression Example .txt", "text": "So for molality, which we got from the first step is zero point 65 equals two divided by x."}, {"title": "Freezing Point depression Example .txt", "text": "Our unknown."}, {"title": "Freezing Point depression Example .txt", "text": "The molar mass entire thing divided by 0.10.1\ncomes from 100 grams."}, {"title": "Freezing Point depression Example .txt", "text": "Remember, we want to deal with kilograms of our solid and we're given 100 grams."}, {"title": "Freezing Point depression Example .txt", "text": "So divide this by 1000, we get 0.1\nkg, bring this over, multiply this out, then bring it back and we at two divided by 0.165 equals x."}, {"title": "Freezing Point depression Example .txt", "text": "And so our x is 121.21\ngrams/mol."}, {"title": "Freezing Point depression Example .txt", "text": "And this is our molar mass."}, {"title": "Balancing Redox reactions example .txt", "text": "So, in this lecture, we want to go from an unbalanced reduction reaction."}, {"title": "Balancing Redox reactions example .txt", "text": "We want to follow seven steps that I've outlined in another lecture and want to get a final net balanced redox reaction."}, {"title": "Balancing Redox reactions example .txt", "text": "So let's follow these seven steps."}, {"title": "Balancing Redox reactions example .txt", "text": "In the first step, we want to find or determine the oxidized atom and the reduced atom."}, {"title": "Balancing Redox reactions example .txt", "text": "So let's find a reduced atom first."}, {"title": "Balancing Redox reactions example .txt", "text": "So, which atom gains electrons?"}, {"title": "Balancing Redox reactions example .txt", "text": "So I've written out the oxidation states for each atom."}, {"title": "Balancing Redox reactions example .txt", "text": "So let's see which atom becomes more negative."}, {"title": "Balancing Redox reactions example .txt", "text": "So, our Mm, or permanganate atom, goes from a plus seven to a plus two."}, {"title": "Balancing Redox reactions example .txt", "text": "That means it gains five electrons."}, {"title": "Balancing Redox reactions example .txt", "text": "So that means our Mm is reduced."}, {"title": "Balancing Redox reactions example .txt", "text": "Now, likewise, let's find an atom that loses those electrons."}, {"title": "Balancing Redox reactions example .txt", "text": "Well, our carbon atom is plus three on this side and plus four on that side."}, {"title": "Balancing Redox reactions example .txt", "text": "And that means when it goes from here to here, it is oxidized."}, {"title": "Balancing Redox reactions example .txt", "text": "It loses those electrons gained by this Mm."}, {"title": "Balancing Redox reactions example .txt", "text": "So our carbon is oxidized."}, {"title": "Balancing Redox reactions example .txt", "text": "We're double step one."}, {"title": "Balancing Redox reactions example .txt", "text": "Let's go to step two."}, {"title": "Balancing Redox reactions example .txt", "text": "And step two."}, {"title": "Balancing Redox reactions example .txt", "text": "We want to write out the two half reactions for our unbalanced equations."}, {"title": "Balancing Redox reactions example .txt", "text": "So we want to write out the oxidation reaction and the reduction reaction."}, {"title": "Balancing Redox reactions example .txt", "text": "So, oxidation basically states that this guy goes from this guy to this guy in here."}, {"title": "Balancing Redox reactions example .txt", "text": "And then the reduction reaction, our ion, goes to this ion."}, {"title": "Balancing Redox reactions example .txt", "text": "So this is our reduction reaction."}, {"title": "Balancing Redox reactions example .txt", "text": "Now, I combine steps three and four in steps."}, {"title": "Balancing Redox reactions example .txt", "text": "In step three, I basically want to balance out the atoms that are not oxygen atoms and not hydrogen atoms."}, {"title": "Balancing Redox reactions example .txt", "text": "So let's start with oxidation reaction."}, {"title": "Balancing Redox reactions example .txt", "text": "So, an oxidation health reaction."}, {"title": "Balancing Redox reactions example .txt", "text": "Let's balance out the carbon atoms."}, {"title": "Balancing Redox reactions example .txt", "text": "So, to balance this carbon atom out, there are two atoms on this side and only one atom on this side."}, {"title": "Balancing Redox reactions example .txt", "text": "That means I want to multiply this guy by two."}, {"title": "Balancing Redox reactions example .txt", "text": "And that's exactly what I do here."}, {"title": "Balancing Redox reactions example .txt", "text": "Now, I have two carbon atoms on this side and two carbon atoms on this side."}, {"title": "Balancing Redox reactions example .txt", "text": "Next, I want to balance out the carbon or the MN atoms on this side in this reduction reaction."}, {"title": "Balancing Redox reactions example .txt", "text": "So, since I have one MN here and one Amen here, it's already balanced."}, {"title": "Balancing Redox reactions example .txt", "text": "So, in the fourth step, let's balance out the oxygen molecules by adding water molecules."}, {"title": "Balancing Redox reactions example .txt", "text": "And let's balance the h atoms by adding H plus ions."}, {"title": "Balancing Redox reactions example .txt", "text": "So let's see our oxidation reaction."}, {"title": "Balancing Redox reactions example .txt", "text": "So, we have four O atoms on this side and only two atoms on this side."}, {"title": "Balancing Redox reactions example .txt", "text": "But I already multiply this carbon dioxide by two."}, {"title": "Balancing Redox reactions example .txt", "text": "That means our oxygens already bounced out."}, {"title": "Balancing Redox reactions example .txt", "text": "So I have four here and four here."}, {"title": "Balancing Redox reactions example .txt", "text": "Two times two."}, {"title": "Balancing Redox reactions example .txt", "text": "So the oxygen is bounced out."}, {"title": "Balancing Redox reactions example .txt", "text": "Let's balance out the h atoms."}, {"title": "Balancing Redox reactions example .txt", "text": "I have two atoms on this side and no h atoms on that side, right?"}, {"title": "Balancing Redox reactions example .txt", "text": "So in order to balance this, I have to add two h atoms on this side."}, {"title": "Balancing Redox reactions example .txt", "text": "That's exactly what I do."}, {"title": "Balancing Redox reactions example .txt", "text": "So I'm done with my oxidation half reaction."}, {"title": "Balancing Redox reactions example .txt", "text": "Let's look at the reduction half reaction."}, {"title": "Balancing Redox reactions example .txt", "text": "Remember, the MNS are already balanced out, so let's balance out oxygen."}, {"title": "Balancing Redox reactions example .txt", "text": "I have four oxygen this side, so that means you have to add four water molecules on this side."}, {"title": "Balancing Redox reactions example .txt", "text": "If I add four water molecules on this side, I balance out the O."}, {"title": "Balancing Redox reactions example .txt", "text": "But now I have to balance out the H, because now I have four times two, eight H ions on this side or atoms on this side."}, {"title": "Balancing Redox reactions example .txt", "text": "That means I balance this guy out by adding eight H plus ions to this side, and I get this following reaction."}, {"title": "Balancing Redox reactions example .txt", "text": "So I'm done with steps three and four."}, {"title": "Balancing Redox reactions example .txt", "text": "Now let's go to step five."}, {"title": "Balancing Redox reactions example .txt", "text": "In step five, you basically want to balance out the entire charge down on this side and this side, and then the entire charge down on this side and this side."}, {"title": "Balancing Redox reactions example .txt", "text": "In other words, on this side of the oxidation half reaction, our charge is neutral."}, {"title": "Balancing Redox reactions example .txt", "text": "On this side, it's not neutral because we have two positive charges."}, {"title": "Balancing Redox reactions example .txt", "text": "So this side is neutral."}, {"title": "Balancing Redox reactions example .txt", "text": "This side is plus two."}, {"title": "Balancing Redox reactions example .txt", "text": "So to make this side zero, I have to add two electrons."}, {"title": "Balancing Redox reactions example .txt", "text": "That's exactly what I do."}, {"title": "Balancing Redox reactions example .txt", "text": "And now my charge is neutral and neutral because these two pluses cancel these two minuses."}, {"title": "Balancing Redox reactions example .txt", "text": "Now let's follow the same steps for this reduction reaction."}, {"title": "Balancing Redox reactions example .txt", "text": "So on this side, I have a minus one and eight pluses."}, {"title": "Balancing Redox reactions example .txt", "text": "That means our charge on this side is plus seven."}, {"title": "Balancing Redox reactions example .txt", "text": "Now on this side, my charge is plus two."}, {"title": "Balancing Redox reactions example .txt", "text": "So I want to neutralize my charges."}, {"title": "Balancing Redox reactions example .txt", "text": "That means if I have plus seven here, I have to add seven electrons, and that's exactly what I do."}, {"title": "Balancing Redox reactions example .txt", "text": "Now, on this side, to neutralize this charge, I have to add two electrons."}, {"title": "Balancing Redox reactions example .txt", "text": "That's exactly what I do."}, {"title": "Balancing Redox reactions example .txt", "text": "I add two electrons."}, {"title": "Balancing Redox reactions example .txt", "text": "But now notice that I have two electrons here and seven electrons here."}, {"title": "Balancing Redox reactions example .txt", "text": "That means I could subtract two electrons from both sides."}, {"title": "Balancing Redox reactions example .txt", "text": "And what happens is this guy cancels out and this guy becomes a five, because seven minus five is seven minus two is five."}, {"title": "Balancing Redox reactions example .txt", "text": "So I'm done."}, {"title": "Balancing Redox reactions example .txt", "text": "Step five."}, {"title": "Balancing Redox reactions example .txt", "text": "In step six, I want to consider the fact that energy or charge is concerned, like mass is concerned."}, {"title": "Balancing Redox reactions example .txt", "text": "And that means I have to whatever amount of electrons lost by one atom or by one side has to be gained by another side."}, {"title": "Balancing Redox reactions example .txt", "text": "So notice on this side, I have two electrons, on this side, I have five electrons."}, {"title": "Balancing Redox reactions example .txt", "text": "That means I want to find a factor or a common factor of five and two."}, {"title": "Balancing Redox reactions example .txt", "text": "And this factor is ten, because two goes into ten five times, and five goes into ten two times."}, {"title": "Balancing Redox reactions example .txt", "text": "So I basically multiply this whole guy out by five, and I multiply this whole guy out by two, and I get the following."}, {"title": "Balancing Redox reactions example .txt", "text": "So five times this guy gives me this, five times this guy gives me this guy five times, two H gives me ten H, and five times this guy gives me ten electrons."}, {"title": "Balancing Redox reactions example .txt", "text": "I multiply this whole guy by two."}, {"title": "Balancing Redox reactions example .txt", "text": "I get two of these guys plus 16 of H pluses plus ten of east equals two of these guys and eight of these guys."}, {"title": "Balancing Redox reactions example .txt", "text": "Now, when I go from step six to seven, I basically want to add these equations up, right?"}, {"title": "Balancing Redox reactions example .txt", "text": "I want to add my two half reactions."}, {"title": "Balancing Redox reactions example .txt", "text": "So I add all the guys on the left side, and then I add all the guys on the right side."}, {"title": "Balancing Redox reactions example .txt", "text": "So I get this whole guy plus nothing more on this side."}, {"title": "Balancing Redox reactions example .txt", "text": "So I go down to my other reactions, plus two of these guys, plus 16 of these guys, plus ten electrons."}, {"title": "Balancing Redox reactions example .txt", "text": "And now I'm done with everything on the left side."}, {"title": "Balancing Redox reactions example .txt", "text": "Now I move on to the right side."}, {"title": "Balancing Redox reactions example .txt", "text": "This guy equals ten carbon dioxide molecules plus two Mm, two plus molecules, right?"}, {"title": "Balancing Redox reactions example .txt", "text": "Plus ten H plus molecules, plus eight water molecules plus ten electrons."}, {"title": "Balancing Redox reactions example .txt", "text": "So this is my equation."}, {"title": "Balancing Redox reactions example .txt", "text": "Now, my next goal before I get to my finalized answer, I have to cross out some things."}, {"title": "Balancing Redox reactions example .txt", "text": "The first thing I crossed out is a ten electron."}, {"title": "Balancing Redox reactions example .txt", "text": "So we have ten electrons here and seven electrons here."}, {"title": "Balancing Redox reactions example .txt", "text": "That cancels out."}, {"title": "Balancing Redox reactions example .txt", "text": "Next, notice that I have 16 H plus ions on this side and ten plus H ions on this side."}, {"title": "Balancing Redox reactions example .txt", "text": "That means I could cancel out this guy by subtracting ten H plus from this side and ten H plus from this side."}, {"title": "Balancing Redox reactions example .txt", "text": "So I canceled out, and 16 minus ten is six."}, {"title": "Balancing Redox reactions example .txt", "text": "So my final equation, my final balanced redox equation, is five H, two C, two four plus two M and minus one four plus six of these guys."}, {"title": "Balancing Redox reactions example .txt", "text": "Subtracting gives me these guys cancel ten carbon dioxide plus two of these guys and eight water molecules."}, {"title": "Balancing Redox reactions example .txt", "text": "And this is my final net redox reaction."}, {"title": "Balancing Redox reactions example .txt", "text": "And it's balanced."}, {"title": "Raoul\u2019s Law for Ideal Fluids .txt", "text": "Today we're going to talk about roll slaw for ideal fluids."}, {"title": "Raoul\u2019s Law for Ideal Fluids .txt", "text": "So what is a pure liquid?"}, {"title": "Raoul\u2019s Law for Ideal Fluids .txt", "text": "A pure liquid is simply a liquid that is not contaminated by any other compound or molecule."}, {"title": "Raoul\u2019s Law for Ideal Fluids .txt", "text": "For example, suppose we have a closed system, a closed container, and inside this container we have pure water."}, {"title": "Raoul\u2019s Law for Ideal Fluids .txt", "text": "But that simply means that the only types of molecules found within our system or water molecules."}, {"title": "Raoul\u2019s Law for Ideal Fluids .txt", "text": "Now, what will happen to our system if it's left untouched?"}, {"title": "Raoul\u2019s Law for Ideal Fluids .txt", "text": "Well, eventually, some of the water molecules found on the surface of the liquid will escape into the gas state and will become gas molecules."}, {"title": "Raoul\u2019s Law for Ideal Fluids .txt", "text": "And this is called evaporation."}, {"title": "Raoul\u2019s Law for Ideal Fluids .txt", "text": "Now, on the rate of evaporation and condensation are equal."}, {"title": "Raoul\u2019s Law for Ideal Fluids .txt", "text": "The system is said to be in dynamic equilibrium."}, {"title": "Raoul\u2019s Law for Ideal Fluids .txt", "text": "At this point, we could measure something called vapor pressure."}, {"title": "Raoul\u2019s Law for Ideal Fluids .txt", "text": "Vapor pressure is the pressure exerted by evaporating molecules or gas molecules found in dynamic equilibrium with the pure liquid molecules."}, {"title": "Raoul\u2019s Law for Ideal Fluids .txt", "text": "Now, what will happen to our system if we add a non volatile compound to our pure substance?"}, {"title": "Raoul\u2019s Law for Ideal Fluids .txt", "text": "Remember, a non volatile compound is a compound that will not evaporate."}, {"title": "Raoul\u2019s Law for Ideal Fluids .txt", "text": "And remember, evaporation only occurs on the surface area of the liquid."}, {"title": "Raoul\u2019s Law for Ideal Fluids .txt", "text": "So therefore, let's look at what happens to our surface area after we add this substance."}, {"title": "Raoul\u2019s Law for Ideal Fluids .txt", "text": "The surface area of the liquid is constant, it remains the same."}, {"title": "Raoul\u2019s Law for Ideal Fluids .txt", "text": "And that's because our system, our container, remains constant."}, {"title": "Raoul\u2019s Law for Ideal Fluids .txt", "text": "It will not change in shape or size."}, {"title": "Raoul\u2019s Law for Ideal Fluids .txt", "text": "So if you take the crosssectional before addition and after addition, the crosssectional area will remain the same."}, {"title": "Raoul\u2019s Law for Ideal Fluids .txt", "text": "What will change however, is the number of pure liquid molecules found on the surface area and this number will decrease."}, {"title": "Raoul\u2019s Law for Ideal Fluids .txt", "text": "And this is because of the presence of nonvolatile compounds."}, {"title": "Raoul\u2019s Law for Ideal Fluids .txt", "text": "Now for example, let's look at the before picture."}, {"title": "Raoul\u2019s Law for Ideal Fluids .txt", "text": "Before addition, we have water molecules found on the surface area."}, {"title": "Raoul\u2019s Law for Ideal Fluids .txt", "text": "And these water molecules will escape and they're going to condense back into the liquid state."}, {"title": "Raoul\u2019s Law for Ideal Fluids .txt", "text": "Now, after the addition, we're going to have some non volatile compounds replacing these molecules."}, {"title": "Raoul\u2019s Law for Ideal Fluids .txt", "text": "And that means less molecules or less pure molecules present on the surface."}, {"title": "Raoul\u2019s Law for Ideal Fluids .txt", "text": "And remember, evaporation occurs on the surface of the liquid."}, {"title": "Raoul\u2019s Law for Ideal Fluids .txt", "text": "So there are less volatile molecules, less molecules that evaporate, less gas molecules will be present at equilibrium."}, {"title": "Raoul\u2019s Law for Ideal Fluids .txt", "text": "And this means the pressure of the vapor pressure is less."}, {"title": "Raoul\u2019s Law for Ideal Fluids .txt", "text": "And this is Rolls law."}, {"title": "Raoul\u2019s Law for Ideal Fluids .txt", "text": "Rolt's law gives us the following equation."}, {"title": "Raoul\u2019s Law for Ideal Fluids .txt", "text": "The vapor pressure after the addition is equal to the mole fraction of the pure substance times the vapor pressure before addition."}, {"title": "Raoul\u2019s Law for Ideal Fluids .txt", "text": "And this is known as Rolls law."}, {"title": "Raoul\u2019s Law for Ideal Fluids .txt", "text": "Now let's look at the addition of a volatile compound to a pure mixture."}, {"title": "Raoul\u2019s Law for Ideal Fluids .txt", "text": "A volatile compound is simply a compound that will evaporate."}, {"title": "Raoul\u2019s Law for Ideal Fluids .txt", "text": "So what happens to our surface area?"}, {"title": "Raoul\u2019s Law for Ideal Fluids .txt", "text": "Well, the surface area remains the same, and that's because once again, our container does not change in shape or size."}, {"title": "Raoul\u2019s Law for Ideal Fluids .txt", "text": "Its cross sectional area remains constant."}, {"title": "Raoul\u2019s Law for Ideal Fluids .txt", "text": "And once again, we have a less pure molecules found on the surface."}, {"title": "Raoul\u2019s Law for Ideal Fluids .txt", "text": "And that's because they're replaced by the new volatile content."}, {"title": "Raoul\u2019s Law for Ideal Fluids .txt", "text": "But now there's a major difference."}, {"title": "Raoul\u2019s Law for Ideal Fluids .txt", "text": "Now we're dealing with a content that is allowed to evaporate."}, {"title": "Raoul\u2019s Law for Ideal Fluids .txt", "text": "So let's look at the difference."}, {"title": "Raoul\u2019s Law for Ideal Fluids .txt", "text": "The before picture, before addition, we only have water molecules or pure molecules found on a surface."}, {"title": "Raoul\u2019s Law for Ideal Fluids .txt", "text": "And these guys will evaporate and will create a certain vapor pressure."}, {"title": "Raoul\u2019s Law for Ideal Fluids .txt", "text": "The vapor pressure is this the after picture?"}, {"title": "Raoul\u2019s Law for Ideal Fluids .txt", "text": "After we add the volatile compound, we're going to have a mixture of the new compound and the old compound found on the surface area."}, {"title": "Raoul\u2019s Law for Ideal Fluids .txt", "text": "But now the red guys, the new compound, are allowed to evaporate."}, {"title": "Raoul\u2019s Law for Ideal Fluids .txt", "text": "So now the vapor pressure will be due to these molecules and these molecules."}, {"title": "Raoul\u2019s Law for Ideal Fluids .txt", "text": "So Roth's law will tell us that the final vapor pressure of our system will be the vapor pressure due to the new guys, plus the vapor pressure due to the old guys."}, {"title": "Raoul\u2019s Law for Ideal Fluids .txt", "text": "So the final pressure is the sum of the two pressures."}, {"title": "Osmosis and Osmotic Pressure.txt", "text": "In this lecture we're going to look at a concept called osmosis."}, {"title": "Osmosis and Osmotic Pressure.txt", "text": "Now, before we talk about osmosis, it's very important to know what entropy is."}, {"title": "Osmosis and Osmotic Pressure.txt", "text": "So if you're not sure about entropy, check out the link below."}, {"title": "Osmosis and Osmotic Pressure.txt", "text": "So one of the most basic definitions of entropy is that entropy is the tendency of a system to even out."}, {"title": "Osmosis and Osmotic Pressure.txt", "text": "For example, let's look at system."}, {"title": "Osmosis and Osmotic Pressure.txt", "text": "This system is composed of two sections connected by a bridge and we have two molecules on this side and eight molecules on this side."}, {"title": "Osmosis and Osmotic Pressure.txt", "text": "What entropy tells us is that eventually three of these molecules will end up on this side and that this system will be the most probable system."}, {"title": "Osmosis and Osmotic Pressure.txt", "text": "So we want a system that's even not uneven or balanced, not on balance, in which we have five molecules here and five molecules here."}, {"title": "Osmosis and Osmotic Pressure.txt", "text": "Let's look at system C.\nNow, in system C we basically have a cell."}, {"title": "Osmosis and Osmotic Pressure.txt", "text": "And this cell is surrounded by semipermeable membrane that allows water molecules in and out but does not allow any size molecules to go in or out."}, {"title": "Osmosis and Osmotic Pressure.txt", "text": "Now, in this cell, however, we have a small hole in the membrane and this hole is large enough to allow the molecules in and out."}, {"title": "Osmosis and Osmotic Pressure.txt", "text": "So water is going to travel in and out and so will the molecules."}, {"title": "Osmosis and Osmotic Pressure.txt", "text": "So eventually, according to what entropy tells us, we're going to want to go from system C to system D. That is, we want to travel from this system to this even system in which we have five molecules on this side on the inside and five molecules on the outside."}, {"title": "Osmosis and Osmotic Pressure.txt", "text": "Now let's look at a third system."}, {"title": "Osmosis and Osmotic Pressure.txt", "text": "Let's look at system E. Now, in system E, we basically have the same system as above, except now our hole is filled in."}, {"title": "Osmosis and Osmotic Pressure.txt", "text": "So we have a continuous circular membrane."}, {"title": "Osmosis and Osmotic Pressure.txt", "text": "So now we can't talk about the side molecules going in and out because side molecules can't go in and out."}, {"title": "Osmosis and Osmotic Pressure.txt", "text": "And that's because of the membrane."}, {"title": "Osmosis and Osmotic Pressure.txt", "text": "The membrane is a barrier to the side molecules."}, {"title": "Osmosis and Osmotic Pressure.txt", "text": "So we must talk about something else."}, {"title": "Osmosis and Osmotic Pressure.txt", "text": "We must talk about the amount of solid molecules per some given volume."}, {"title": "Osmosis and Osmotic Pressure.txt", "text": "And in fact, that's concentration."}, {"title": "Osmosis and Osmotic Pressure.txt", "text": "So our concentration on the outside, because we have more molecules, is higher than the concentration on the inside."}, {"title": "Osmosis and Osmotic Pressure.txt", "text": "So what will happen?"}, {"title": "Osmosis and Osmotic Pressure.txt", "text": "Well, entropy tells us that in this case, the only thing that can move, which is a solvent and the water will move and water will travel from the inside to the outside."}, {"title": "Osmosis and Osmotic Pressure.txt", "text": "So our cell will shrink in size and our concentration will increase in size because now we have less volume."}, {"title": "Osmosis and Osmotic Pressure.txt", "text": "But the same amount of solution, now the concentration on the outside will decrease because now we have the same amount, but a larger volume, a larger amount of water."}, {"title": "Osmosis and Osmotic Pressure.txt", "text": "And that means eventually our concentrations will equal out."}, {"title": "Osmosis and Osmotic Pressure.txt", "text": "So now let's define osmosis."}, {"title": "Osmosis and Osmotic Pressure.txt", "text": "Osmosis is the movement of solvent."}, {"title": "Osmosis and Osmotic Pressure.txt", "text": "In our case, water from an area of a lower side concentration to an area of a higher sized concentration."}, {"title": "Osmosis and Osmotic Pressure.txt", "text": "So in the system above, osmosis occurred from the inside the cell into the outside, because water moves from a lower concentration to a higher concentration."}, {"title": "Osmosis and Osmotic Pressure.txt", "text": "Okay?"}, {"title": "Osmosis and Osmotic Pressure.txt", "text": "Now, we can also talk about something called osmotic pressure."}, {"title": "Osmosis and Osmotic Pressure.txt", "text": "Osmotic pressure is the pressure required to stop osmosis."}, {"title": "Osmosis and Osmotic Pressure.txt", "text": "So, for example, suppose we apply some pressure to our cell membrane, and if this pressure equals asthmatic pressure, well, then no osmosis will occur, no movement of water will occur."}, {"title": "Osmosis and Osmotic Pressure.txt", "text": "And this becomes very important when you're talking about hydrostatic pressure and asthmatic pressure in the capillaries of our body."}, {"title": "Osmosis and Osmotic Pressure.txt", "text": "So the last thing I want to talk about is a formula."}, {"title": "Osmosis and Osmotic Pressure.txt", "text": "And this formula could be only used when we talk about ideal conditions."}, {"title": "Osmosis and Osmotic Pressure.txt", "text": "So ideal solutions and solutions that have very low or small concentrations."}, {"title": "Osmosis and Osmotic Pressure.txt", "text": "Now, if you want to look at a problem using this formula, check out the link below."}, {"title": "Osmosis and Osmotic Pressure.txt", "text": "Now let's look at the formula."}, {"title": "Osmosis and Osmotic Pressure.txt", "text": "The formula basically states that osmotic pressure is equal to molarity of solution times our gas constants r times our temperature in Kelvin times I."}, {"title": "Osmosis and Osmotic Pressure.txt", "text": "Now, I is called a vant half factor."}, {"title": "Osmosis and Osmotic Pressure.txt", "text": "And basically, that's the number of particles a single sided molecule breaks into."}, {"title": "Osmosis and Osmotic Pressure.txt", "text": "So, for example, sodium chloride breaks into two particles."}, {"title": "Osmosis and Osmotic Pressure.txt", "text": "So for an ideal for an ideal solution, this I would be two."}, {"title": "Methyl Compounds .txt", "text": "So let's discuss methyl compounds."}, {"title": "Methyl Compounds .txt", "text": "Now, methyl compounds are simply compounds that have a side chain or side group ch three."}, {"title": "Methyl Compounds .txt", "text": "And that ch three is attached covalently to some other atomyl chloride compound given here, x."}, {"title": "Methyl Compounds .txt", "text": "Now, this x could be anything, and here are a few examples."}, {"title": "Methyl Compounds .txt", "text": "We have methyl chloride, methyl alcohol, or methanol."}, {"title": "Methyl Compounds .txt", "text": "We have methylamine, and we have methylcyanide."}, {"title": "Methyl Compounds .txt", "text": "So let's compare methyl compounds to something that we already spoke about methane."}, {"title": "Methyl Compounds .txt", "text": "In fact, methane is methyl compound where the x has been replaced with an H. Now, methane is the simplest alkane, and methane has symmetry."}, {"title": "Methyl Compounds .txt", "text": "And that's because the carbon, the central carbon, is attached to four identical H atoms, 1234."}, {"title": "Methyl Compounds .txt", "text": "And that means all the ch bonds will be exactly the same as the other."}, {"title": "Methyl Compounds .txt", "text": "All these ch bonds will be SP three hybridized, and the angles between a two bonds will be 109.5\ndegrees."}, {"title": "Methyl Compounds .txt", "text": "So, once again, each bond is identical because we have a single carbon atom attached to four identical H atoms."}, {"title": "Methyl Compounds .txt", "text": "Hence, our bonds are all SP three hybridized."}, {"title": "Methyl Compounds .txt", "text": "So let's take this methane and compare it to a methylcogddam."}, {"title": "Methyl Compounds .txt", "text": "So here we have a methylcogdam, where we replace the H with an x."}, {"title": "Methyl Compounds .txt", "text": "This X could be any atom."}, {"title": "Methyl Compounds .txt", "text": "Now, we have bonds that are not all identical."}, {"title": "Methyl Compounds .txt", "text": "In other words, we still have three of these ch bonds, but now we have a different CX bond."}, {"title": "Methyl Compounds .txt", "text": "For example, if I replace this x with a chloride atom, so this is a chloride."}, {"title": "Methyl Compounds .txt", "text": "That means the chloride, since the chloride is more electronegative than either the carbon or the H atoms, that means that chloride will pull electrons more strongly than either of the H atom."}, {"title": "Methyl Compounds .txt", "text": "And so there will be an unequal electron density in this bond."}, {"title": "Methyl Compounds .txt", "text": "Electrons will be closer to this x atom, to this CL atom than to the carbon atom."}, {"title": "Methyl Compounds .txt", "text": "And that means that this will be a slightly asymmetrical molecule, asymmetrical compound."}, {"title": "Methyl Compounds .txt", "text": "And so it will slightly deviate from this methane compound."}, {"title": "Methyl Compounds .txt", "text": "Therefore, the bonds won't be exactly SP three hybridized."}, {"title": "Methyl Compounds .txt", "text": "However, the difference is so slight that for the most part, we can approximate these bonds to be SP three hybridized."}, {"title": "Methyl Compounds .txt", "text": "But you should know that because of the difference in electronegativity, because this CX bond is not the same as the ch bond, there will be slight differences or deviations from this methane compound."}, {"title": "Class Clapeyron Example .txt", "text": "So we are given alcohol, and we know that our alcohol at 20 degrees Celsius has a vapor pressure of 40 mercury."}, {"title": "Class Clapeyron Example .txt", "text": "And at 61 degrees Celsius, it has a vapor pressure of 360 millimeters of mercury."}, {"title": "Class Clapeyron Example .txt", "text": "And our goal is to find a change in entropy of vaporization of 1 mol of alcohol."}, {"title": "Class Clapeyron Example .txt", "text": "So to find that, we have to use something called a class here to clay for an equation."}, {"title": "Class Clapeyron Example .txt", "text": "Now, if you want to learn more about this equation, where it comes from, and why it's important, check out the link below."}, {"title": "Class Clapeyron Example .txt", "text": "So let's look at our equation."}, {"title": "Class Clapeyron Example .txt", "text": "Notice that in this equation we have three knowns and two unknowns."}, {"title": "Class Clapeyron Example .txt", "text": "So we have a constant R, it's a gas constant."}, {"title": "Class Clapeyron Example .txt", "text": "We know that."}, {"title": "Class Clapeyron Example .txt", "text": "Now we have the pressure and we have a temperature."}, {"title": "Class Clapeyron Example .txt", "text": "What we don't have is this C constant and this entropy of vaporization."}, {"title": "Class Clapeyron Example .txt", "text": "In fact, that's exactly what we want to find."}, {"title": "Class Clapeyron Example .txt", "text": "So if we somehow know this, we can find that."}, {"title": "Class Clapeyron Example .txt", "text": "But an even better tactic would be to get rid of this."}, {"title": "Class Clapeyron Example .txt", "text": "So notice we have a single equation and two unknowns."}, {"title": "Class Clapeyron Example .txt", "text": "So mathematically we can't solve this."}, {"title": "Class Clapeyron Example .txt", "text": "But if we come up with a system of equations, two equations and two unknowns, we could somehow manipulate the two equations, get rid of that C, and solve for our unknown."}, {"title": "Class Clapeyron Example .txt", "text": "And in fact, that's exactly what we're going to do."}, {"title": "Class Clapeyron Example .txt", "text": "Notice we have initial conditions and final conditions."}, {"title": "Class Clapeyron Example .txt", "text": "So why not come up with two of these equations, one for the initial condition and one for the final condition."}, {"title": "Class Clapeyron Example .txt", "text": "That's exactly what we do here."}, {"title": "Class Clapeyron Example .txt", "text": "This one is for our final conditions, where PF and TF are P final and T final."}, {"title": "Class Clapeyron Example .txt", "text": "And this guy is for our initial conditions, p initial and T initial."}, {"title": "Class Clapeyron Example .txt", "text": "And in order to get rid of these two C's, let's subtract this guy from this guy."}, {"title": "Class Clapeyron Example .txt", "text": "Okay, that's exactly what we do right here."}, {"title": "Class Clapeyron Example .txt", "text": "So this guy minus this guy."}, {"title": "Class Clapeyron Example .txt", "text": "Now notice we have the equal sign here."}, {"title": "Class Clapeyron Example .txt", "text": "We're going to subtract everything on this side first, then everything on this side next."}, {"title": "Class Clapeyron Example .txt", "text": "So natural log of P final, minus natural log of P initial, and we get exactly this."}, {"title": "Class Clapeyron Example .txt", "text": "Next, we subtract this whole section from this whole section."}, {"title": "Class Clapeyron Example .txt", "text": "So first we take this and we put it here."}, {"title": "Class Clapeyron Example .txt", "text": "That's exactly what we did."}, {"title": "Class Clapeyron Example .txt", "text": "Next, we subtract this guy from this guy."}, {"title": "Class Clapeyron Example .txt", "text": "But notice we have a negative sign here, and that means we have to distribute this negative sign to here and here."}, {"title": "Class Clapeyron Example .txt", "text": "So this guy becomes positive."}, {"title": "Class Clapeyron Example .txt", "text": "So we get plus this guy, and this negative makes this positive a negative."}, {"title": "Class Clapeyron Example .txt", "text": "So this guy becomes a negative."}, {"title": "Class Clapeyron Example .txt", "text": "And now notice we have a plus C and a minus C. So the C's cancel and we get just this guy plus this guy."}, {"title": "Class Clapeyron Example .txt", "text": "And that's exactly what we have right here."}, {"title": "Class Clapeyron Example .txt", "text": "Now our next step is to basically equate this guy, to simply this guy and rewrite the equations to a better looking formula so this guy, using the logs of logs, we can rewrite in this format."}, {"title": "Class Clapeyron Example .txt", "text": "So natural log of P final divided by P initial equals."}, {"title": "Class Clapeyron Example .txt", "text": "Now, notice on this side, we have two common terms or one common term."}, {"title": "Class Clapeyron Example .txt", "text": "This guy and this guy are two of the same term."}, {"title": "Class Clapeyron Example .txt", "text": "It's the same term."}, {"title": "Class Clapeyron Example .txt", "text": "So basically, you want to take this guy out of our equation and leave this guy and this guy alone."}, {"title": "Class Clapeyron Example .txt", "text": "So negative change in anthropy vaporization over r, our common term, times one over t, final minus one over T initial."}, {"title": "Class Clapeyron Example .txt", "text": "Notice that here this was a positive."}, {"title": "Class Clapeyron Example .txt", "text": "But since we're taking a negative out, this becomes a negative."}, {"title": "Class Clapeyron Example .txt", "text": "And to check that, we multiply this out and we should get this form."}, {"title": "Class Clapeyron Example .txt", "text": "And, in fact, we do."}, {"title": "Class Clapeyron Example .txt", "text": "Now, our final step before we plug in chug is simply to rewrite this so that we have this thing on one side and everything else, all the knowns on the other side."}, {"title": "Class Clapeyron Example .txt", "text": "So you want the unknown on one side and the knowns on the other side."}, {"title": "Class Clapeyron Example .txt", "text": "And this is what we get."}, {"title": "Class Clapeyron Example .txt", "text": "So what we do is we find the common denominator here, multiply this by Ti and this by TF, bring everything over, bring the R over, and then bring the negative over, and we get this."}, {"title": "Class Clapeyron Example .txt", "text": "Finally, we plug in all our information."}, {"title": "Class Clapeyron Example .txt", "text": "So our R, it's 8.31\njoules per mole times Kelvin, times natural log of 360 or 40, which is simply nine times."}, {"title": "Class Clapeyron Example .txt", "text": "Now, we have to use our temperature in Kelvin, and that means we have to convert from celebrates to Kelvin by simply adding 273 to each temperature."}, {"title": "Class Clapeyron Example .txt", "text": "So this is what we get."}, {"title": "Class Clapeyron Example .txt", "text": "We basically plug this into our calculator."}, {"title": "Class Clapeyron Example .txt", "text": "We solve, and we get approximately 44 kilojoules per mole."}, {"title": "Class Clapeyron Example .txt", "text": "So this is how much energy is required or how much enthalpy is required to basically vaporize liquid alcohol into gas alcohol."}, {"title": "Alkenes and Double Bonds .txt", "text": "So let's begin our discussion on alkines."}, {"title": "Alkenes and Double Bonds .txt", "text": "Now, alkanes, like alkanes, are simply hydrocarbons."}, {"title": "Alkenes and Double Bonds .txt", "text": "But unlike alkanes, alkines contain a double bond."}, {"title": "Alkenes and Double Bonds .txt", "text": "And in this lecture, we're going to examine exactly what a double bond is."}, {"title": "Alkenes and Double Bonds .txt", "text": "So let's begin by looking at the simplest alkhine, known as ethylene, also known as ethylene."}, {"title": "Alkenes and Double Bonds .txt", "text": "Now, ethylene is composed of two carbons connected by a double bond and two H atoms found on both sides of those carbons."}, {"title": "Alkenes and Double Bonds .txt", "text": "So let's begin by building or creating this ethylene molecule."}, {"title": "Alkenes and Double Bonds .txt", "text": "So let's create it using a methylratical."}, {"title": "Alkenes and Double Bonds .txt", "text": "Recall that a methylradical is simply a carbon atom attached to three H bonds or three H atoms via SP two hybridized orbitals."}, {"title": "Alkenes and Double Bonds .txt", "text": "So each of these sigma bonds, covalent sigma bonds, are SP two hybridized."}, {"title": "Alkenes and Double Bonds .txt", "text": "And we also have a pure two p orbital that contains a single electron within that two p orbital."}, {"title": "Alkenes and Double Bonds .txt", "text": "So, to build this ethylene, let's simply replace the H atom here with a methylene atom with a ch two atom, or a ch two molecule."}, {"title": "Alkenes and Double Bonds .txt", "text": "Sorry."}, {"title": "Alkenes and Double Bonds .txt", "text": "What do we get?"}, {"title": "Alkenes and Double Bonds .txt", "text": "Well, if we say if we replace this with a ch two molecule, we get the following picture."}, {"title": "Alkenes and Double Bonds .txt", "text": "So, we get a carbon carbon bond."}, {"title": "Alkenes and Double Bonds .txt", "text": "We get four PH bonds, two on each side."}, {"title": "Alkenes and Double Bonds .txt", "text": "And we have a two p orbital on both of these carbons that has an electron in each orbital."}, {"title": "Alkenes and Double Bonds .txt", "text": "So first, we let's examine what type of bond this carbon carbon bond is."}, {"title": "Alkenes and Double Bonds .txt", "text": "So this carbon donates an SP two hybridized orbital."}, {"title": "Alkenes and Double Bonds .txt", "text": "Remember, these guys are SP two hybridized."}, {"title": "Alkenes and Double Bonds .txt", "text": "And this carbon also donates an SP two hybridized orbital."}, {"title": "Alkenes and Double Bonds .txt", "text": "So when we combine two atomic orbitals, we must form two molecular orbitals according to quantum mechanics."}, {"title": "Alkenes and Double Bonds .txt", "text": "And so our lower end energy more stable molecular orbital will be due to the overlap of these green regions."}, {"title": "Alkenes and Double Bonds .txt", "text": "And we will get the following SP two, SP two sigma bonding molecular orbital, or simply mo."}, {"title": "Alkenes and Double Bonds .txt", "text": "So the two electrons, one electron in each of this carbon in each of these SP two hybridized orbitals will go into this lower in energy bonding molecular orbital."}, {"title": "Alkenes and Double Bonds .txt", "text": "Now, we're also going to have this antibonding molecular orbital."}, {"title": "Alkenes and Double Bonds .txt", "text": "But since it's high in energy and it's morphed and it's less stable, the electrons will not go into that orbital."}, {"title": "Alkenes and Double Bonds .txt", "text": "So both electrons will be in this molecular orbital."}, {"title": "Alkenes and Double Bonds .txt", "text": "And so this covalent bond is SP two SP two hybridized sigma bonding molecular orbital."}, {"title": "Alkenes and Double Bonds .txt", "text": "And now notice one more thing."}, {"title": "Alkenes and Double Bonds .txt", "text": "Notice we have these two two p orbitals, and they're both parallel to one another."}, {"title": "Alkenes and Double Bonds .txt", "text": "In other words, these two guides are parallel to one another, and they're perpendicular to either of these ch bonds."}, {"title": "Alkenes and Double Bonds .txt", "text": "And so, because these guides are parallel and because they have the same exact energy as one another, they will create an overlapping condition."}, {"title": "Alkenes and Double Bonds .txt", "text": "So, once again, just like we have an overlap here, we're going to have an overlap here."}, {"title": "Alkenes and Double Bonds .txt", "text": "So let's combine these two p orbitals."}, {"title": "Alkenes and Double Bonds .txt", "text": "So here we have a two p orbital from this carbon combined with a two P orbital from this carbon."}, {"title": "Alkenes and Double Bonds .txt", "text": "Once again, we're combining two atomic orbitals to form two different molecular orbitals."}, {"title": "Alkenes and Double Bonds .txt", "text": "However, now they're no longer Sigma."}, {"title": "Alkenes and Double Bonds .txt", "text": "They're called pi."}, {"title": "Alkenes and Double Bonds .txt", "text": "Okay?"}, {"title": "Alkenes and Double Bonds .txt", "text": "So one is a pi, or two P, two pi bonding molecular orbital."}, {"title": "Alkenes and Double Bonds .txt", "text": "And the second one is a two P two pi antibonding molecular orbital."}, {"title": "Alkenes and Double Bonds .txt", "text": "So, there will be one known between these two orbitals."}, {"title": "Alkenes and Double Bonds .txt", "text": "And that means this guy will be higher in energy and less stable."}, {"title": "Alkenes and Double Bonds .txt", "text": "And so electrons will tend to go into the lower in energy more stable bond."}, {"title": "Alkenes and Double Bonds .txt", "text": "So this pi bond here."}, {"title": "Alkenes and Double Bonds .txt", "text": "Now, notice one difference between our Sigma and our Pi bonds."}, {"title": "Alkenes and Double Bonds .txt", "text": "Both of these SP two hybridized orbitals contain 33% or 33.3% as character, while these two p orbitals contain no as character."}, {"title": "Alkenes and Double Bonds .txt", "text": "So that means, because these guys contain the more stable S character, these are more stable."}, {"title": "Alkenes and Double Bonds .txt", "text": "So that means they're lower in energy than these two P orbitals."}, {"title": "Alkenes and Double Bonds .txt", "text": "So when these two orbitals, when these two p orbitals combine to form a pi orbital, this pi orbital is higher in energy than this SP two SP two Sigma bonding molecular orbital."}, {"title": "Alkenes and Double Bonds .txt", "text": "And that means this will be more stable than our Pi bond."}, {"title": "Alkenes and Double Bonds .txt", "text": "So now let's redraw our diagram for this silent molecule."}, {"title": "Alkenes and Double Bonds .txt", "text": "So here we have our two carbons, and they create an SP two hybridized molecular orbital given here."}, {"title": "Alkenes and Double Bonds .txt", "text": "And it also creates this interaction here between our pure two P orbitals."}, {"title": "Alkenes and Double Bonds .txt", "text": "Remember, this electron is found at the same time in this region, as well as in this region."}, {"title": "Alkenes and Double Bonds .txt", "text": "So that means there will be interaction between these two lobes here."}, {"title": "Alkenes and Double Bonds .txt", "text": "And so this is known as our Pi bond, and this is known as our Sigma Bond."}, {"title": "Alkenes and Double Bonds .txt", "text": "And once again, this pi bond will be higher in energy than this Sigma Bond."}, {"title": "Alkenes and Double Bonds .txt", "text": "Another way of drawing this a more simpler way is simply with two bonds here, two dashes here."}, {"title": "Alkenes and Double Bonds .txt", "text": "Now, notice that this is a Sigma bond, and the top one is a Pi bond."}, {"title": "Alkenes and Double Bonds .txt", "text": "So let's review."}, {"title": "Alkenes and Double Bonds .txt", "text": "The Sigma bond contains more S character and is therefore lower in energy and more stable or stronger."}, {"title": "Alkenes and Double Bonds .txt", "text": "Because remember, the more stable something is, the more stronger it is then the Pi bond."}, {"title": "Alkenes and Double Bonds .txt", "text": "Therefore, the Pi bond is less stable because it's higher in energy, and therefore it's more reactive."}, {"title": "Alkenes and Double Bonds .txt", "text": "Now, whenever we input energy to break our Pi bond or to break our double bond, our pi bonds break first."}, {"title": "Alkenes and Double Bonds .txt", "text": "So let's look at one more important detail about our double bonds."}, {"title": "Alkenes and Double Bonds .txt", "text": "So, this is a single bond."}, {"title": "Alkenes and Double Bonds .txt", "text": "This is an ethylene molecule."}, {"title": "Alkenes and Double Bonds .txt", "text": "So notice that in an ethylene molecule, we have one Sigma bond, and the Sigma bond is able to rotate."}, {"title": "Alkenes and Double Bonds .txt", "text": "So we create confirmations or confirmations of ethane."}, {"title": "Alkenes and Double Bonds .txt", "text": "So we could have an eclipse confirm, and we could have a staggered confirm."}, {"title": "Alkenes and Double Bonds .txt", "text": "Now, notice what happens in our double bond molecule."}, {"title": "Alkenes and Double Bonds .txt", "text": "So here we have the following ethylene lean."}, {"title": "Alkenes and Double Bonds .txt", "text": "So, notice that these ch bonds on Ethylene lean are on the same plane."}, {"title": "Alkenes and Double Bonds .txt", "text": "And these two orbitals here, this Pi orbital is created by an overlap of two P orbitals down perpendicular to either of BCH bonds."}, {"title": "Alkenes and Double Bonds .txt", "text": "And notice what happens."}, {"title": "Alkenes and Double Bonds .txt", "text": "Notice now there is no rotation."}, {"title": "Alkenes and Double Bonds .txt", "text": "And that's because if there was rotation, these two P orbitals would no longer be in parallel."}, {"title": "Alkenes and Double Bonds .txt", "text": "When I rotate these, these guys would lose that overlap and therefore would destabilize the molecule."}, {"title": "Alkenes and Double Bonds .txt", "text": "So that means, because these two P orbitals like to stay in parallel to one another, they like to stay in the same plane."}, {"title": "Alkenes and Double Bonds .txt", "text": "This double bond will not allow rotation."}, {"title": "Alkenes and Double Bonds .txt", "text": "And so our ethylene molecule will not rotate in the same way that this molecule will rotate."}, {"title": "Kinetic Molecular Theory .txt", "text": "From everyday experience we know that gas molecules behave differently than liquid and solid molecules."}, {"title": "Kinetic Molecular Theory .txt", "text": "In order to understand the complex behavior of gas molecules scientists came up with four major assumptions about the way ideal gases behave."}, {"title": "Kinetic Molecular Theory .txt", "text": "And they call these assumptions the kinetic molecular theory."}, {"title": "Kinetic Molecular Theory .txt", "text": "Now, from the math, a Niagara point of view, this isn't really a theory because under real conditions these assumptions don't hold."}, {"title": "Kinetic Molecular Theory .txt", "text": "Yes, these assumptions are important to make because they allow us to come up with concrete conclusions about the behavior of gas molecules."}, {"title": "Kinetic Molecular Theory .txt", "text": "So let's begin."}, {"title": "Kinetic Molecular Theory .txt", "text": "The first assumption is the fact that volume of gas molecules is zero."}, {"title": "Kinetic Molecular Theory .txt", "text": "So where does this assumption come from?"}, {"title": "Kinetic Molecular Theory .txt", "text": "Well, it comes from the observation that gases are easily compressed and mixed very well."}, {"title": "Kinetic Molecular Theory .txt", "text": "And this is because the distance between the molecules is much larger than the size of the molecules."}, {"title": "Kinetic Molecular Theory .txt", "text": "Now let's look at our inflated ball."}, {"title": "Kinetic Molecular Theory .txt", "text": "Within our ball, we have lots of different molecules."}, {"title": "Kinetic Molecular Theory .txt", "text": "But the difference between any two molecules is much greater than the size of the molecule itself."}, {"title": "Kinetic Molecular Theory .txt", "text": "And that's why we can compress it because when we compress it, there's lots of space for the molecules to move."}, {"title": "Kinetic Molecular Theory .txt", "text": "On the contrary, on solids and liquids the density is much higher and so there is not too much space for them to move."}, {"title": "Kinetic Molecular Theory .txt", "text": "And that's why we can't compress them easily."}, {"title": "Kinetic Molecular Theory .txt", "text": "And that's exactly why when we take this inflated ball, we see that we can easily compress it because there's lots of space for the molecules to move."}, {"title": "Kinetic Molecular Theory .txt", "text": "But if this a ball was filled with solid or liquid, I would not be able to compress it without changing its shape or volume."}, {"title": "Kinetic Molecular Theory .txt", "text": "Let's look at the second assumption."}, {"title": "Kinetic Molecular Theory .txt", "text": "Gases move at high velocities in all different directions."}, {"title": "Kinetic Molecular Theory .txt", "text": "So what's the observation or what's the experience from everyday life that tells us that gas is, in fact move at high velocities?"}, {"title": "Kinetic Molecular Theory .txt", "text": "Well, for example, if you forgot to wash your feet or you've been wearing your shoes for way too long, you know that if you take off your shoes and there's a girl or a voice sitting across the room, they will definitely smell you instantaneously."}, {"title": "Kinetic Molecular Theory .txt", "text": "That's why you better keep your shoes on."}, {"title": "Kinetic Molecular Theory .txt", "text": "That's because when you take off your shoes the molecules of air trap in your socks and in your shoes escape and move at very high speeds in all different directions."}, {"title": "Kinetic Molecular Theory .txt", "text": "So the person sitting across the room from you will definitely smell you."}, {"title": "Kinetic Molecular Theory .txt", "text": "So you better keep those shoes on."}, {"title": "Kinetic Molecular Theory .txt", "text": "So the second assumption about high velocities also accounts for the fact that gases will expand into any container quickly and completely."}, {"title": "Kinetic Molecular Theory .txt", "text": "Let's look at our third assumption."}, {"title": "Kinetic Molecular Theory .txt", "text": "So, gas molecules exert no forces on one another due to mass and charge."}, {"title": "Kinetic Molecular Theory .txt", "text": "From everyday experience we know that if we take an object and drop it, it will slide down."}, {"title": "Kinetic Molecular Theory .txt", "text": "Well, why does it slide down?"}, {"title": "Kinetic Molecular Theory .txt", "text": "Because the Earth, a much greater mass, pulls the object and this object pulls the Earth as well."}, {"title": "Kinetic Molecular Theory .txt", "text": "But the Earth is so large, it doesn't really move too much."}, {"title": "Kinetic Molecular Theory .txt", "text": "And in fact, any two objects that have mass will exert a pulling force."}, {"title": "Kinetic Molecular Theory .txt", "text": "Now, the same way charge also exerts a pulling and an attraction force."}, {"title": "Kinetic Molecular Theory .txt", "text": "Now, all these pulling attraction forces can be neglected in a gas system."}, {"title": "Kinetic Molecular Theory .txt", "text": "Well, this fifth part is not really an assumption."}, {"title": "Kinetic Molecular Theory .txt", "text": "It's more of a conclusion."}, {"title": "Kinetic Molecular Theory .txt", "text": "Now, average kinetic energy of molecules is proportional to the temperature."}, {"title": "Kinetic Molecular Theory .txt", "text": "And that simply means if we increase our temperature, we have more kinetic energy."}, {"title": "Kinetic Molecular Theory .txt", "text": "And one observation regarding this assumption is that reactions occur quicker when our temperatures are higher."}, {"title": "Kinetic Molecular Theory .txt", "text": "And that's because there are more collisions between any molecules."}, {"title": "Kinetic Molecular Theory .txt", "text": "And so these colliding molecules are allowed to react, and so they create products."}, {"title": "Kinetic Molecular Theory .txt", "text": "And that's why our rates are higher."}, {"title": "Kinetic Molecular Theory .txt", "text": "Now, I want to mention one more thing."}, {"title": "Kinetic Molecular Theory .txt", "text": "Now, recall that kinetic energy is equal to one half mass times velocity squared."}, {"title": "Kinetic Molecular Theory .txt", "text": "So suppose I have two molecules, one heavy molecule and one light molecule with the same kinetic energy."}, {"title": "Kinetic Molecular Theory .txt", "text": "Well, according to this formula, if the kinetic energies are the same, then the higher or the heavier molecule will have a lower velocity, while the lighter molecule will have a higher velocity."}, {"title": "Kinetic Molecular Theory .txt", "text": "We could also talk about the average velocities of the molecules, and that's simply average of all the molecules found in our system."}, {"title": "Kinetic Molecular Theory .txt", "text": "So, on average, if you pull out a molecule from our system, it will have an average speed."}, {"title": "Kinetic Molecular Theory .txt", "text": "So this CIS assumption directly goes into a concept called Effusion and diffusion."}, {"title": "Elements and Isotopes.txt", "text": "Now we already spoke about atoms and atomic structure and we said that atoms are the building blocks of our world of mass and matter."}, {"title": "Elements and Isotopes.txt", "text": "Now there are many different types of atoms that exist and something called a periodic table represents all these atoms in a certain way."}, {"title": "Elements and Isotopes.txt", "text": "Now, over 100 different types of atoms exist and each atom is called an element."}, {"title": "Elements and Isotopes.txt", "text": "Now each element found on the periodic table of elements is represented in the following way where this x is the symbol of our atom."}, {"title": "Elements and Isotopes.txt", "text": "Now in this case it's just x."}, {"title": "Elements and Isotopes.txt", "text": "It's a hypothetical symbol."}, {"title": "Elements and Isotopes.txt", "text": "But for example, carbon has the letter C and oxygen has the letter O."}, {"title": "Elements and Isotopes.txt", "text": "Now this A and this C are usually numbers but in this case we're going to use letters."}, {"title": "Elements and Isotopes.txt", "text": "The A is the atomic mass and the Z is the atomic number of our element."}, {"title": "Elements and Isotopes.txt", "text": "Now the atomic mass is the mass of that element."}, {"title": "Elements and Isotopes.txt", "text": "It's the number of protons and the number of neutrons."}, {"title": "Elements and Isotopes.txt", "text": "Now note that electrons are not counted Naratomic mass because their mass is much smaller than that the proton or the neutron."}, {"title": "Elements and Isotopes.txt", "text": "Now the atomic number is the number of protons of our element."}, {"title": "Elements and Isotopes.txt", "text": "Now that number, the atomic number is the identity number of that element."}, {"title": "Elements and Isotopes.txt", "text": "It's used to identify our element."}, {"title": "Elements and Isotopes.txt", "text": "It's the fingerprint of that element."}, {"title": "Elements and Isotopes.txt", "text": "And that's because any element can have different number of electrons or neutrons but it will always have the same number of protons."}, {"title": "Elements and Isotopes.txt", "text": "And that's why you could use the atomic number to identify our x, our element."}, {"title": "Elements and Isotopes.txt", "text": "The second that the number of protons changes that means our element also changes."}, {"title": "Elements and Isotopes.txt", "text": "Now let's go into something called isotopes of elements."}, {"title": "Elements and Isotopes.txt", "text": "Now, two or more atoms that contain the same number of protons mean they're the same elements but have different number of neutrons, are called isotopes of that same."}, {"title": "Elements and Isotopes.txt", "text": "Let's look at a very common example of carbon."}, {"title": "Elements and Isotopes.txt", "text": "Now carbon has three isotopes."}, {"title": "Elements and Isotopes.txt", "text": "Now in each case because this is a carbon atom it must have the same number of Z."}, {"title": "Elements and Isotopes.txt", "text": "The atomic number must be the same."}, {"title": "Elements and Isotopes.txt", "text": "In other words, all three have six protons."}, {"title": "Elements and Isotopes.txt", "text": "But notice carbon twelve has six neutrons."}, {"title": "Elements and Isotopes.txt", "text": "Carbon 13 has seven neutrons and carbon 14 has eight neutrons thereby giving the atomic mass six plus 612, six plus 713 and six plus eight is 14."}, {"title": "Elements and Isotopes.txt", "text": "So that makes sense because to get the atomic mass to get the a you have to add up the protons and neutrons."}, {"title": "Elements and Isotopes.txt", "text": "Now there is a unit that scientists created to deal with very, very small amounts of atoms."}, {"title": "Elements and Isotopes.txt", "text": "Now the AMU, or atomic mass unit is the unit of mass used for elements and compounds."}, {"title": "Elements and Isotopes.txt", "text": "Now by definition we define that one atom, a single atom of carbon."}, {"title": "Elements and Isotopes.txt", "text": "Twelve is composed of twelve AMU and everything else is relative to this amount."}, {"title": "Elements and Isotopes.txt", "text": "For example, an H atom is one AMU and it's relative to this."}, {"title": "Elements and Isotopes.txt", "text": "In other words, this is twelve times that's heavier in terms of AMU than an H atom."}, {"title": "Elements and Isotopes.txt", "text": "A single h atom."}, {"title": "Elements and Isotopes.txt", "text": "Now, note that this is one atom of carbon."}, {"title": "Elements and Isotopes.txt", "text": "That's a very tiny amount."}, {"title": "Elements and Isotopes.txt", "text": "It's much, much smaller than grams or kilograms or pounds or anything else."}, {"title": "Elements and Isotopes.txt", "text": "This is a very small amount."}, {"title": "Elements and Isotopes.txt", "text": "So AMU is not a very large charge measurement."}, {"title": "Crystalline Solids and Amorphous Solids .txt", "text": "So, from experiencing the world around us, we know that solids come in many different forms, sizes and shapes."}, {"title": "Crystalline Solids and Amorphous Solids .txt", "text": "Now, in this lecture, we're going to look at exactly that."}, {"title": "Crystalline Solids and Amorphous Solids .txt", "text": "We're going to examine the different type of structures formed by solids."}, {"title": "Crystalline Solids and Amorphous Solids .txt", "text": "So two main types of structures exist, and we'll talk about Crystalline Solids or simply crystals and amorphous solids."}, {"title": "Crystalline Solids and Amorphous Solids .txt", "text": "So let's begin with the crystalline solids."}, {"title": "Crystalline Solids and Amorphous Solids .txt", "text": "So all Crystalline Solids or simply crystals have a very well ordered shape or structure."}, {"title": "Crystalline Solids and Amorphous Solids .txt", "text": "And because of that, they have a very sharp melting point."}, {"title": "Crystalline Solids and Amorphous Solids .txt", "text": "What that means is that the melting point's range is very small."}, {"title": "Crystalline Solids and Amorphous Solids .txt", "text": "It melts over a very, very small range of temperature."}, {"title": "Crystalline Solids and Amorphous Solids .txt", "text": "Now."}, {"title": "Crystalline Solids and Amorphous Solids .txt", "text": "Four main types of Crystalline solids or simply crystals exist."}, {"title": "Crystalline Solids and Amorphous Solids .txt", "text": "Ionic Crystalline solids."}, {"title": "Crystalline Solids and Amorphous Solids .txt", "text": "Metallic Crystalline solids."}, {"title": "Crystalline Solids and Amorphous Solids .txt", "text": "Molecular Crystalline solids and network covalent crystalline solids."}, {"title": "Crystalline Solids and Amorphous Solids .txt", "text": "Now, let's begin with our ionic crystals."}, {"title": "Crystalline Solids and Amorphous Solids .txt", "text": "Now, these crystals consist of ions that are held together by electrostatic forces."}, {"title": "Crystalline Solids and Amorphous Solids .txt", "text": "Electrostatic forces are forces between positively charged ions and negatively charged ions of different atoms."}, {"title": "Crystalline Solids and Amorphous Solids .txt", "text": "Now, let's see in some examples."}, {"title": "Crystalline Solids and Amorphous Solids .txt", "text": "Sodium chloride is an ionic crystal."}, {"title": "Crystalline Solids and Amorphous Solids .txt", "text": "Lithium chloride is also an ionic crystal."}, {"title": "Crystalline Solids and Amorphous Solids .txt", "text": "Calcium chloride or calcium dichloride is also an ionic crystal."}, {"title": "Crystalline Solids and Amorphous Solids .txt", "text": "And basically, whenever an alkaline metal or an alkaline earth metal reacts with a halogen, these guys will always produce, or will most of the time actually will always produce ionic crystals."}, {"title": "Crystalline Solids and Amorphous Solids .txt", "text": "Now let's look at metallic crystals."}, {"title": "Crystalline Solids and Amorphous Solids .txt", "text": "Now, these guys consist of single metal molecules that are held together by a sea of electrons."}, {"title": "Crystalline Solids and Amorphous Solids .txt", "text": "And examples include any type of alkali metal or alkaline earth metal."}, {"title": "Crystalline Solids and Amorphous Solids .txt", "text": "For example, a composite which actually isn't an alkaline or alkali metal, but is a transition metal, but still it's a metal that has a metallic solid structure."}, {"title": "Crystalline Solids and Amorphous Solids .txt", "text": "Other examples are sodium metal or potassium metal or leafy metal or calcium metal."}, {"title": "Crystalline Solids and Amorphous Solids .txt", "text": "Any of these guys have a metallic like structure or metallic crystal structure."}, {"title": "Crystalline Solids and Amorphous Solids .txt", "text": "So now let's look at the third type of Crystalline Solids known as molecular solids."}, {"title": "Crystalline Solids and Amorphous Solids .txt", "text": "Now, these crystals, or these Crystalline solids consist of molecules held together by intermolecular forces called down their balls forces."}, {"title": "Crystalline Solids and Amorphous Solids .txt", "text": "And examples include ice."}, {"title": "Crystalline Solids and Amorphous Solids .txt", "text": "In other words, when you freeze ice, when you take energy away from water and form ice, the water molecules form a very structured formation."}, {"title": "Crystalline Solids and Amorphous Solids .txt", "text": "And this creates what we know as ice."}, {"title": "Crystalline Solids and Amorphous Solids .txt", "text": "And ice are called molecular crystals or molecular solids."}, {"title": "Crystalline Solids and Amorphous Solids .txt", "text": "The fourth and final type of Crystalline Solids we're going to look at are network covalent crystals."}, {"title": "Crystalline Solids and Amorphous Solids .txt", "text": "Now, these consist of network of atoms or molecules held together by covalent bonds."}, {"title": "Crystalline Solids and Amorphous Solids .txt", "text": "These covalent bonds can be both non polar and polar covalent."}, {"title": "Crystalline Solids and Amorphous Solids .txt", "text": "Now, an example is diamonds."}, {"title": "Crystalline Solids and Amorphous Solids .txt", "text": "So what's the structure of a diamond?"}, {"title": "Crystalline Solids and Amorphous Solids .txt", "text": "Diamond consists of solely carbon atoms held together by covalent bonds."}, {"title": "Crystalline Solids and Amorphous Solids .txt", "text": "These Sigma covalent bonds are very strong, and that's exactly why our diamonds are so strong."}, {"title": "Crystalline Solids and Amorphous Solids .txt", "text": "It's very hard to break diamonds."}, {"title": "Crystalline Solids and Amorphous Solids .txt", "text": "Now let's look at the second type of structures of solids."}, {"title": "Crystalline Solids and Amorphous Solids .txt", "text": "And these guys are known as amorphous solids."}, {"title": "Crystalline Solids and Amorphous Solids .txt", "text": "Now, these guys don't really have a well structured shape and because of this, they melt over a very wide range of temperatures."}, {"title": "Crystalline Solids and Amorphous Solids .txt", "text": "Examples of this include some plastics and some glass."}, {"title": "Crystalline Solids and Amorphous Solids .txt", "text": "Now, we should also mention that there is another type of solid or another type of formations that solid solids form."}, {"title": "Crystalline Solids and Amorphous Solids .txt", "text": "And this is called polymers."}, {"title": "Crystalline Solids and Amorphous Solids .txt", "text": "Now, we can have both polymers of amorphous solids and polymers of crystalline solids."}, {"title": "Crystalline Solids and Amorphous Solids .txt", "text": "Now, when we melt polymer solids very quickly, we get amorphous solids."}, {"title": "Crystalline Solids and Amorphous Solids .txt", "text": "When we melt polymers very slowly over a very long range of time, we get crystalline solids."}, {"title": "Crystalline Solids and Amorphous Solids .txt", "text": "Now, some examples of biopolymers biological polymers include DNA proteins which are basically composed of many amino acids."}, {"title": "Crystalline Solids and Amorphous Solids .txt", "text": "Macromolecules such as carbohydrates glycogen, for example, starch."}, {"title": "Crystalline Solids and Amorphous Solids .txt", "text": "All these guys are examples of biological polymers."}, {"title": "Crystalline Solids and Amorphous Solids .txt", "text": "And, for example, this marker is composed of a plant plastic polymer."}, {"title": "Crystalline Solids and Amorphous Solids .txt", "text": "And in fact, many different plastics are composed of polymers of single units of molecules."}, {"title": "Electromotive force.txt", "text": "So just like an object will travel from an area of higher gravitational potential to a near year of low gravitational potential, so will an electron travel from an area of higher electric potential to a nearby of lower electric potential."}, {"title": "Electromotive force.txt", "text": "So that means in electrochemical cells called voltaic cells, electrons flow from the Higher electric potential electrode, the lower electric potential electrode."}, {"title": "Electromotive force.txt", "text": "So that means they travel from the anode electrode to the cathode electrode."}, {"title": "Electromotive force.txt", "text": "So we can define something called the electromotive force or simply EMF as the difference in this electric potential between the anode and the cathode."}, {"title": "Electromotive force.txt", "text": "So to really understand what the Electric Motor Force is, we have to explore a concept called Electric Potential Energy."}, {"title": "Electromotive force.txt", "text": "So electric potential energy, or simply electrical work is equal to the charge of an object times the change in electrical potential."}, {"title": "Electromotive force.txt", "text": "Now, we just said the change in electrical potential between the animal and the capital is simply EMF."}, {"title": "Electromotive force.txt", "text": "So this is our EMF."}, {"title": "Electromotive force.txt", "text": "So in order to understand what the EMF is, we have to really understand what charges and what electrical work or electrical potential energy is."}, {"title": "Electromotive force.txt", "text": "So let's look at electrical work first."}, {"title": "Electromotive force.txt", "text": "So electrical potential energy is similar to gravitational potential energy."}, {"title": "Electromotive force.txt", "text": "So we know that any two objects say this marker and this marker will pull each other and this pull will be due to their masses."}, {"title": "Electromotive force.txt", "text": "And the pull or the force is given by the gravitational constant."}, {"title": "Electromotive force.txt", "text": "Time mass one times mass two divided by the distance between them."}, {"title": "Electromotive force.txt", "text": "Now, the electrical potential energy is similar to this concept, except now they will pull each other not due to mass, but due to charge."}, {"title": "Electromotive force.txt", "text": "So if this object has a charge one and this object has charge two, and their charges are opposite, then they will pull each other."}, {"title": "Electromotive force.txt", "text": "Now, if the charge are the same charge, they will push away."}, {"title": "Electromotive force.txt", "text": "And that's the difference between electrical potential energy and gravitational potential energy."}, {"title": "Electromotive force.txt", "text": "So let's look at what charge is."}, {"title": "Electromotive force.txt", "text": "Charge is simply the amount of electrons found in some object."}, {"title": "Electromotive force.txt", "text": "And charge is measured in units called coulombs."}, {"title": "Electromotive force.txt", "text": "And one electron."}, {"title": "Electromotive force.txt", "text": "One electron has a charge of 1.622 times ten to the negative."}, {"title": "Electromotive force.txt", "text": "19 coulombs."}, {"title": "Electromotive force.txt", "text": "So that means two electrons will be two times this amount, three electrons, three times this amount, and so on."}, {"title": "Electromotive force.txt", "text": "Now, my question is, how many electrons are found in one coulomb of charge?"}, {"title": "Electromotive force.txt", "text": "Well, to find that answer, we must divide one coulomb by 1.622\ntimes ten to 19 coulombs per electron."}, {"title": "Electromotive force.txt", "text": "And that will give us 6.24 times 18 electrons."}, {"title": "Electromotive force.txt", "text": "So this many electrons will be found in one coulomb of charge."}, {"title": "Electromotive force.txt", "text": "That means a coulomb is a pretty big amount of charge."}, {"title": "Electromotive force.txt", "text": "So whenever someone says one coulem of charge moves from this position to this position, that means 6.24\ntimes ten to the 18 electrons move from this position to this position."}, {"title": "Electromotive force.txt", "text": "That's what a coulomb is."}, {"title": "Electromotive force.txt", "text": "That's what charges it's."}, {"title": "Electromotive force.txt", "text": "The movement of electrons from some point A to some point B."}, {"title": "Electromotive force.txt", "text": "So, now that we know what electrical work is and what charges, we can rearrange this formula to give us the change in electric potential."}, {"title": "Electromotive force.txt", "text": "So, by bringing this guy over to this side, we get electrical work divided by charge."}, {"title": "Electromotive force.txt", "text": "And by the way, electrical work, like any work, has the units of Joules."}, {"title": "Electromotive force.txt", "text": "So the units of electrical work divided by charge is Joules divided by Coulomb."}, {"title": "Electromotive force.txt", "text": "And this equals our changing electrical potential, which is also the voltage difference."}, {"title": "Electromotive force.txt", "text": "And which is also what we said before is the electromotive force or EMF."}, {"title": "Electromotive force.txt", "text": "Now, whenever we talk about the EMF of an electrochemical cell, we could also call our EMF the cell voltage because we're talking about an electrochemical cell."}, {"title": "Electromotive force.txt", "text": "And the cell voltage shows how much work can be done for every coulomb produced by a redox reaction in an electrochemical cell."}, {"title": "Electromotive force.txt", "text": "So that basically says that when in an electrochemical cell, one coolant of charge moves from the anode to the cathode, x amount of work can be done."}, {"title": "Electromotive force.txt", "text": "So let's now look at the difference between this battery or this electric chemical cell and this smaller electrochemical cell."}, {"title": "Electromotive force.txt", "text": "So let us examine the difference between this D battery and the AAA battery."}, {"title": "Electromotive force.txt", "text": "Well, according to this label, it says that our electromotive force of this deep battery is exactly 1.5 volts."}, {"title": "Electromotive force.txt", "text": "So EMF of D is 1.5\nvolts."}, {"title": "Electromotive force.txt", "text": "What is the EMF of the AAA battery?"}, {"title": "Electromotive force.txt", "text": "Well, the EMF of this guy is also 1.5 volts."}, {"title": "Electromotive force.txt", "text": "So EMF is 1.5 volts."}, {"title": "Electromotive force.txt", "text": "That's weird."}, {"title": "Electromotive force.txt", "text": "How come this more expensive larger battery has the same EMF as the smaller and cheaper battery?"}, {"title": "Electromotive force.txt", "text": "Well, let's examine exactly what EMF is."}, {"title": "Electromotive force.txt", "text": "Remember, EMF is the amount of energy produced when warm Coulomb travels from this anode to this cathode."}, {"title": "Electromotive force.txt", "text": "Or said another way, when 6.24\ntimes ten to the 18 electrons travel from this point to this point, they produce 1.5 joy or joules of work."}, {"title": "Electromotive force.txt", "text": "So what this means is that in this battery and in this battery, when one Coulomb charge travels from the animals to the cathode, both batteries produce the same amount of work."}, {"title": "Electromotive force.txt", "text": "The same energy is released to do work."}, {"title": "Electromotive force.txt", "text": "So what's the difference between the D and the AAA?"}, {"title": "Electromotive force.txt", "text": "Why is this more expensive?"}, {"title": "Electromotive force.txt", "text": "Well, it's more expensive because it's bigger."}, {"title": "Electromotive force.txt", "text": "It could hold more charge."}, {"title": "Electromotive force.txt", "text": "That's the difference."}, {"title": "Electromotive force.txt", "text": "This guy holds much more charge and eventually the charge here will run out."}, {"title": "Electromotive force.txt", "text": "But this guy will still have enough charge."}, {"title": "Electromotive force.txt", "text": "So the charge and electrons will continue traveling from here to here."}, {"title": "Electromotive force.txt", "text": "So this guy literally houses more electrons and that's why it's more expensive."}, {"title": "Electromotive force.txt", "text": "So, for example, this battery will be able to run a light bulb for say, 15 minutes, while this guy will run a light bulb for say, 4 hours."}, {"title": "Electromotive force.txt", "text": "So this guy literally has more electrons in it than this."}, {"title": "Electromotive force.txt", "text": "And that's the difference."}, {"title": "Electromotive force.txt", "text": "That's why this is more expensive than this."}, {"title": "Henderson Hasselbalch example .txt", "text": "In this example, we begin with 0.05 molar of Peruvic acid and 0.07 molar of sodium Peruvine."}, {"title": "Henderson Hasselbalch example .txt", "text": "Our ka for our acid is 3.1 times ten to negative three."}, {"title": "Henderson Hasselbalch example .txt", "text": "We want to find the PH of our buffer solution."}, {"title": "Henderson Hasselbalch example .txt", "text": "Once we mix these two guys, there are two methods we can use use to find the PH of the buffer solution."}, {"title": "Henderson Hasselbalch example .txt", "text": "Our first method involves the Henderson Hasselblack formula."}, {"title": "Henderson Hasselbalch example .txt", "text": "And if you haven't seen this formula before or you don't know where it comes from, check out the link below."}, {"title": "Henderson Hasselbalch example .txt", "text": "The second method is to simply use the Ka."}, {"title": "Henderson Hasselbalch example .txt", "text": "So let's do the first method first."}, {"title": "Henderson Hasselbalch example .txt", "text": "So our PH is equal to PKA plus or log of concentration of conjugate base divided by the concentration of conjugate acid."}, {"title": "Henderson Hasselbalch example .txt", "text": "This equals, remember, PKA is simply negative log of Ka."}, {"title": "Henderson Hasselbalch example .txt", "text": "So this equals negative log of Ka."}, {"title": "Henderson Hasselbalch example .txt", "text": "And our Ka is 3.1\ntimes tens of eight."}, {"title": "Henderson Hasselbalch example .txt", "text": "So we plug it into here plus log of this guy over this guy we get 0.07 over 0.05\napproximately equals we plug this into our calculator and we get 2.65."}, {"title": "Henderson Hasselbalch example .txt", "text": "So that's our PH."}, {"title": "Henderson Hasselbalch example .txt", "text": "Now let's find using the same PH using the Ka."}, {"title": "Henderson Hasselbalch example .txt", "text": "So remember, our equation for conjugate acid and conjugate base is conjugate acid plus our water gives us conjugate base plus our hydronium ion."}, {"title": "Henderson Hasselbalch example .txt", "text": "So let's write the equilibrium equation for this guy."}, {"title": "Henderson Hasselbalch example .txt", "text": "So, Ka, our acid ionization constant is equal to the concentration of hydronium times the concentration of Pyruvate divided by the concentration of pyruvic acid."}, {"title": "Henderson Hasselbalch example .txt", "text": "Now, initially we begin with some amount of this guy and some amount of this guy, right?"}, {"title": "Henderson Hasselbalch example .txt", "text": "We don't have any of this guy."}, {"title": "Henderson Hasselbalch example .txt", "text": "Or we approximate this guy to be zero."}, {"title": "Henderson Hasselbalch example .txt", "text": "At the end of our equilibrium, this guy is x."}, {"title": "Henderson Hasselbalch example .txt", "text": "And since this and this is a ratio of one to one, this guy must be x two."}, {"title": "Henderson Hasselbalch example .txt", "text": "So the concentration of this guy increases by x."}, {"title": "Henderson Hasselbalch example .txt", "text": "The concentration of this guy increases by x, and the concentration of this guy decreases by x because this guy dissociates into this guy."}, {"title": "Henderson Hasselbalch example .txt", "text": "So we get our hydronium concentration, we represent as x."}, {"title": "Henderson Hasselbalch example .txt", "text": "Our pyruvate concentration we present as x because we begin with this concentration divide by since we begin with this amount of Peruvic acid and then some dissociates into the conjugate base, we say that it's 0.5 minus x."}, {"title": "Henderson Hasselbalch example .txt", "text": "Now we approximate because the x is much smaller than 0.5 or 0.7 or 0.5."}, {"title": "Henderson Hasselbalch example .txt", "text": "We approximate this to be 0.7."}, {"title": "Henderson Hasselbalch example .txt", "text": "X divided by 0.5 equals our Ka."}, {"title": "Henderson Hasselbalch example .txt", "text": "So equals 3.1 times ten negative three."}, {"title": "Henderson Hasselbalch example .txt", "text": "We bring the 0.5\nover."}, {"title": "Henderson Hasselbalch example .txt", "text": "Then we divide by 0.7 and we get x equals 0.221."}, {"title": "Henderson Hasselbalch example .txt", "text": "And notice that this is indeed much smaller than 0.5 or zero point 75."}, {"title": "Henderson Hasselbalch example .txt", "text": "So our approximation was accurate."}, {"title": "Henderson Hasselbalch example .txt", "text": "Now, to find a PH, we basically plug in the concentration into our PH into our negative log."}, {"title": "Henderson Hasselbalch example .txt", "text": "And we get negative log 00221 approximates to 2.65."}, {"title": "Henderson Hasselbalch example .txt", "text": "And this equals this guy."}, {"title": "Henderson Hasselbalch example .txt", "text": "So these are two ways, two methods that you can use to calculate the PH of a buffer solution."}, {"title": "Avogadro\u2019s Number and Moles .txt", "text": "Today we're going to look at a very simple concept but one that's confused very often."}, {"title": "Avogadro\u2019s Number and Moles .txt", "text": "We're going to look at avocado's number and moles."}, {"title": "Avogadro\u2019s Number and Moles .txt", "text": "Now, avogadjo's number, just like any other number, is simply a number but it's a very large number."}, {"title": "Avogadro\u2019s Number and Moles .txt", "text": "More specifically, it's 6.022 times ten to 23."}, {"title": "Avogadro\u2019s Number and Moles .txt", "text": "So it's a very, very big number."}, {"title": "Avogadro\u2019s Number and Moles .txt", "text": "Now, avogatro number is usually used in relation with moles."}, {"title": "Avogadro\u2019s Number and Moles .txt", "text": "Now, a mole which is represented by lowercase N is a group that consists of an avogadro's number of anything."}, {"title": "Avogadro\u2019s Number and Moles .txt", "text": "Now, in the same way that a dozen represents a group of twelve, a mole represents a group of this many things."}, {"title": "Avogadro\u2019s Number and Moles .txt", "text": "Now, we could have a dozen roses, a dozen eggs, a dozen chickens, a dozen chairs, cars, books, people."}, {"title": "Avogadro\u2019s Number and Moles .txt", "text": "In the same way we can have a mole of anything."}, {"title": "Avogadro\u2019s Number and Moles .txt", "text": "Now, the only thing is a mole is usually used for very small things."}, {"title": "Avogadro\u2019s Number and Moles .txt", "text": "For example, we can talk about a mole of protons, a mole of electrons, a mole of atoms, a mole of molecules."}, {"title": "Avogadro\u2019s Number and Moles .txt", "text": "Because these things are very very small it usually doesn't make sense to say a mole of people because that's impossible."}, {"title": "Avogadro\u2019s Number and Moles .txt", "text": "We can't have a mole of people because we only have 7 billion people in the world."}, {"title": "Avogadro\u2019s Number and Moles .txt", "text": "So moles are used for very small quantities of something."}, {"title": "Avogadro\u2019s Number and Moles .txt", "text": "For example, we can talk about a mole of atoms which is 6.22 times ten to 23 atoms."}, {"title": "Avogadro\u2019s Number and Moles .txt", "text": "But we can't really or it doesn't make sense to talk about a mole of books or a mole of x because I don't think we have this many eggs in the world."}, {"title": "Avogadro\u2019s Number and Moles .txt", "text": "Maybe we do, but it's just a very large number."}, {"title": "Avogadro\u2019s Number and Moles .txt", "text": "Now, moles and a bogondo's number can be used to answer the following questions."}, {"title": "Avogadro\u2019s Number and Moles .txt", "text": "For example how many molecules of water are in 20 grams of water?"}, {"title": "Avogadro\u2019s Number and Moles .txt", "text": "Now, to answer this question we have to first figure out how many moles are in 20 grams of water."}, {"title": "Avogadro\u2019s Number and Moles .txt", "text": "And then we multiply that by our avocado's number remembering that 1 mol of anything is this many atoms or molecules in our case."}, {"title": "Avogadro\u2019s Number and Moles .txt", "text": "Now, let's take our amount in grams of water and divide it by our molecular weight of water which we can find on the periodic table which is 18 grams/mol."}, {"title": "Avogadro\u2019s Number and Moles .txt", "text": "The way we found that is we simply added up the atomic weight of oxygen plus two atomic weights of H because we have two H atoms."}, {"title": "Avogadro\u2019s Number and Moles .txt", "text": "So 16 for oxygen and two times one for H two gives us 18 grams/mol for a single water molecule."}, {"title": "Avogadro\u2019s Number and Moles .txt", "text": "So 20 grams of water divided by 18 grams/mol we see that the grams cancel, the moles go on top and we get one point moles of water."}, {"title": "Avogadro\u2019s Number and Moles .txt", "text": "So this means within our 20 grams of water there are one point eleven moles of water."}, {"title": "Avogadro\u2019s Number and Moles .txt", "text": "Now, we know that in 1 mol of anything there are this many molecules."}, {"title": "Avogadro\u2019s Number and Moles .txt", "text": "So to find the number of molecules in one point eleven moles of water we simply multiply this number by Avogastro's number."}, {"title": "Avogadro\u2019s Number and Moles .txt", "text": "So we get 6.22 times ten to the 23 atoms."}, {"title": "Avogadro\u2019s Number and Moles .txt", "text": "Or actually, in our case, this should be molecules."}, {"title": "Avogadro\u2019s Number and Moles .txt", "text": "Molecules per mole, times one point eleven moles of water."}, {"title": "Avogadro\u2019s Number and Moles .txt", "text": "So the moles cancel and we're left with 6.68 times tens of 23 molecules of water."}, {"title": "Avogadro\u2019s Number and Moles .txt", "text": "So this is how many molecules are found in 20 grams of water."}, {"title": "Avogadro\u2019s Number and Moles .txt", "text": "Now, suppose I asked the question, how many atoms are found in 20 grams of water?"}, {"title": "Avogadro\u2019s Number and Moles .txt", "text": "Well, that means we take this number and multiply it by three."}, {"title": "Avogadro\u2019s Number and Moles .txt", "text": "Why?"}, {"title": "Avogadro\u2019s Number and Moles .txt", "text": "Well, this is a molecule, but an atom represents a single atom within this molecule."}, {"title": "Avogadro\u2019s Number and Moles .txt", "text": "So we have one atom, two three atoms, one oxygen and two H atoms."}, {"title": "Avogadro\u2019s Number and Moles .txt", "text": "So we have three atoms."}, {"title": "Avogadro\u2019s Number and Moles .txt", "text": "So we take this number and multiply it by three to find the amount of atoms found in 20 grams of water."}, {"title": "Resonance Forms Example .txt", "text": "So in a previous lecture, we spoke about and defined what resident forms and resonance is."}, {"title": "Resonance Forms Example .txt", "text": "Now, this lecture we're going to do three examples shown here, and our goal will be to find as many resident forms as possible."}, {"title": "Resonance Forms Example .txt", "text": "So remember, whenever we're trying to do resonance and we're trying to find resonant forms, we're only moving electrons."}, {"title": "Resonance Forms Example .txt", "text": "The atoms never actually move."}, {"title": "Resonance Forms Example .txt", "text": "So let's redraw this molecule with the atoms being in the same exact place as shown here."}, {"title": "Resonance Forms Example .txt", "text": "So we have the H atom, the C, the H atom here."}, {"title": "Resonance Forms Example .txt", "text": "We have our N atom and the two H's here."}, {"title": "Resonance Forms Example .txt", "text": "So notice our atoms haven't actually moved."}, {"title": "Resonance Forms Example .txt", "text": "But what has happened?"}, {"title": "Resonance Forms Example .txt", "text": "Well, what can we do here?"}, {"title": "Resonance Forms Example .txt", "text": "Well, look at this plus charge here."}, {"title": "Resonance Forms Example .txt", "text": "We don't like having charges."}, {"title": "Resonance Forms Example .txt", "text": "Charges means destabilization."}, {"title": "Resonance Forms Example .txt", "text": "We want to stabilize this lowest dot structure by removing this plus one charge."}, {"title": "Resonance Forms Example .txt", "text": "The way we can do that is basically take this double bond here, or take these two electrons, a pair of electrons, and use arrow formulasm to move these electrons here."}, {"title": "Resonance Forms Example .txt", "text": "Remember, an arrow, a double headed arrow simply means that a pair of electrons is being moved."}, {"title": "Resonance Forms Example .txt", "text": "So these two electrons are being moved from here on to here."}, {"title": "Resonance Forms Example .txt", "text": "And so let's draw our two electrons here."}, {"title": "Resonance Forms Example .txt", "text": "Now, what has happened is this N now has five electrons, and that means this has been neutralized to a neutral charge."}, {"title": "Resonance Forms Example .txt", "text": "But now this carbon has a positive charge."}, {"title": "Resonance Forms Example .txt", "text": "And so let's draw a plus charge here."}, {"title": "Resonance Forms Example .txt", "text": "And this concludes our resonance forms."}, {"title": "Resonance Forms Example .txt", "text": "For this molecule, we have two major resonance forms."}, {"title": "Resonance Forms Example .txt", "text": "So let's go to part two."}, {"title": "Resonance Forms Example .txt", "text": "In part two, we have the following molecule, where we have two oxygen, carbon, carbon, and three HS."}, {"title": "Resonance Forms Example .txt", "text": "So our goal will be to draw as many resonance forms or as many major resin forms as possible."}, {"title": "Resonance Forms Example .txt", "text": "So let's begin by moving electrons."}, {"title": "Resonance Forms Example .txt", "text": "Well, what's one way that we can move electrons here?"}, {"title": "Resonance Forms Example .txt", "text": "Well, we can basically take a pair of electrons here."}, {"title": "Resonance Forms Example .txt", "text": "We can create a double bond here, and these two electrons can be moved onto this oxygen, and we will create the following molecule or compound."}, {"title": "Resonance Forms Example .txt", "text": "Remember, our atoms have not actually moved, so our atoms remain the same."}, {"title": "Resonance Forms Example .txt", "text": "What does move are electrons."}, {"title": "Resonance Forms Example .txt", "text": "So now this has essentially flipped."}, {"title": "Resonance Forms Example .txt", "text": "Now we have a negative charge on this upper oxygen and a neutral charge on the bottom."}, {"title": "Resonance Forms Example .txt", "text": "Well, what's another way that we can rearrange things?"}, {"title": "Resonance Forms Example .txt", "text": "Well, we can surely take this bond here, the double bond, the pair of electrons, and move it onto this oxygen here."}, {"title": "Resonance Forms Example .txt", "text": "So let's do that."}, {"title": "Resonance Forms Example .txt", "text": "So once again, keeping in mind that the resonant form represents an arrow that looks like this."}, {"title": "Resonance Forms Example .txt", "text": "And once again, no atoms are moved."}, {"title": "Resonance Forms Example .txt", "text": "Now, we have the following picture."}, {"title": "Resonance Forms Example .txt", "text": "In this picture, we have now developed a minus on top, a minus on the bottom, and we have a plus one on the carbon."}, {"title": "Resonance Forms Example .txt", "text": "So now we have the following species."}, {"title": "Resonance Forms Example .txt", "text": "Now, notice here we have only one negative charge, one negative charge."}, {"title": "Resonance Forms Example .txt", "text": "But in this rest and form, we have two negative charges and a positive charge."}, {"title": "Resonance Forms Example .txt", "text": "Remember, whenever we have a lot of charge, a lot of charge stabilizes the structure."}, {"title": "Resonance Forms Example .txt", "text": "And that basically means that these two resonant forms will be more important than this resin form."}, {"title": "Resonance Forms Example .txt", "text": "So these are our major resonant forms."}, {"title": "Resonance Forms Example .txt", "text": "Now let's jump to part three."}, {"title": "Resonance Forms Example .txt", "text": "In part three, we basically have a very similar structure to this, except now we have an H bonded to our oxygen, so we have a neutral atom."}, {"title": "Resonance Forms Example .txt", "text": "So let's continue and let's draw what's one other way that we can draw this in terms of resonance?"}, {"title": "Resonance Forms Example .txt", "text": "Well, we can surely take this pair of electron, place it here, and these electrons will move on to this oxygen, and we will develop the following lewis dot structure or resin four."}, {"title": "Resonance Forms Example .txt", "text": "Remember, our atoms don't actually move."}, {"title": "Resonance Forms Example .txt", "text": "Atoms stay the same."}, {"title": "Resonance Forms Example .txt", "text": "But now we have the following picture."}, {"title": "Resonance Forms Example .txt", "text": "So here we have an H two."}, {"title": "Resonance Forms Example .txt", "text": "Now, notice what happens."}, {"title": "Resonance Forms Example .txt", "text": "This has 12345."}, {"title": "Resonance Forms Example .txt", "text": "So this develops a plus one charge."}, {"title": "Resonance Forms Example .txt", "text": "This develops a negative one charge."}, {"title": "Resonance Forms Example .txt", "text": "And so an overall net charge on this higher molecule is still zero, just like it is here."}, {"title": "Resonance Forms Example .txt", "text": "So let's draw one other resin form for this molecule or compound."}, {"title": "Resonance Forms Example .txt", "text": "What's another way we can draw it?"}, {"title": "Resonance Forms Example .txt", "text": "Well, what if we just simply take this bond and move it back here?"}, {"title": "Resonance Forms Example .txt", "text": "Well, let's try that."}, {"title": "Resonance Forms Example .txt", "text": "So we will have the following picture."}, {"title": "Resonance Forms Example .txt", "text": "Now, this carbon will develop a plus one charge."}, {"title": "Resonance Forms Example .txt", "text": "This will be neutral."}, {"title": "Resonance Forms Example .txt", "text": "Let's build our electrons here."}, {"title": "Resonance Forms Example .txt", "text": "And this guy here will have a negative charge."}, {"title": "Resonance Forms Example .txt", "text": "So we're going to have an overall net charge of zero."}, {"title": "Resonance Forms Example .txt", "text": "So what happened here?"}, {"title": "Resonance Forms Example .txt", "text": "Well, here we have electrons that went onto here."}, {"title": "Resonance Forms Example .txt", "text": "So this concludes our major resonance structures."}, {"title": "Resonance Forms Example .txt", "text": "Now, of course, more resonant structures exist, but these guys are the major resonance structures for these compounds or molecules."}, {"title": "The pH scale .txt", "text": "So in solutions where water is our solvent, we can talk about measuring the concentration of hydrogen ions in our water."}, {"title": "The pH scale .txt", "text": "Even pure water has some concentration of hydrogen ions."}, {"title": "The pH scale .txt", "text": "And that's because pure water dissociates into H plus and hydroxide."}, {"title": "The pH scale .txt", "text": "So at any given time, we can measure the concentration of of this guy in terms of molar amount."}, {"title": "The pH scale .txt", "text": "Now, if you want to learn more about how H plus relates to acids and oh, Myers relates to bases, check out the link below."}, {"title": "The pH scale .txt", "text": "So what happens when we add some substance to our pure water, our PR substance?"}, {"title": "The pH scale .txt", "text": "Well, for example, suppose we add HDL to our water."}, {"title": "The pH scale .txt", "text": "What happens?"}, {"title": "The pH scale .txt", "text": "Well, Htl dissociates its a Hydride ion and a chloride ion."}, {"title": "The pH scale .txt", "text": "So our concentration or amount in molar of H plus will increase because we have the H coming from water and the H coming from HDL."}, {"title": "The pH scale .txt", "text": "And so our concentration of our solution will increase."}, {"title": "The pH scale .txt", "text": "Now we can measure the concentrations in terms of molar amount, but the values we get can range from anywhere from ten to the negative 14 molar."}, {"title": "The pH scale .txt", "text": "That's a very small number."}, {"title": "The pH scale .txt", "text": "That's one divided by 100 trillion."}, {"title": "The pH scale .txt", "text": "And they could become as large as ten molar."}, {"title": "The pH scale .txt", "text": "Okay, so this becomes a problem."}, {"title": "The pH scale .txt", "text": "This is very inconvenient because say if you want to graph concentration in molar versus temperature, a graph would not be possible because our y scale would be just too big."}, {"title": "The pH scale .txt", "text": "The range would be too big."}, {"title": "The pH scale .txt", "text": "So scientists came up with a way or a convenient way of expressing the concentration of our hydrogen ions in solution."}, {"title": "The pH scale .txt", "text": "And this convenient way is called a PH scale."}, {"title": "The pH scale .txt", "text": "The PH scale is defined by the following formula."}, {"title": "The pH scale .txt", "text": "PH of our solution is equal to negative log of the concentration of hydrogen ions."}, {"title": "The pH scale .txt", "text": "And that's equivalent to saying negative log of the concentration of hydronium ions."}, {"title": "The pH scale .txt", "text": "Because this guy and this guy are really one and the same."}, {"title": "The pH scale .txt", "text": "So let's see why logs are convenient."}, {"title": "The pH scale .txt", "text": "But first, let's see what logs are."}, {"title": "The pH scale .txt", "text": "Logs are simply another way of representing exponents."}, {"title": "The pH scale .txt", "text": "And if you want to find an exponent, you use logs."}, {"title": "The pH scale .txt", "text": "For example, suppose we're given this equation here."}, {"title": "The pH scale .txt", "text": "So ten to the negative four is equal to one over 10,000, which is another way of saying 0.1."}, {"title": "The pH scale .txt", "text": "Okay?"}, {"title": "The pH scale .txt", "text": "So on a lock scale, this can be represented in the following way."}, {"title": "The pH scale .txt", "text": "Where this is our base, our result and our exponent."}, {"title": "The pH scale .txt", "text": "We get log base ten, log base ten."}, {"title": "The pH scale .txt", "text": "In the inside we get our result."}, {"title": "The pH scale .txt", "text": "So 0.0001\nand that equals to our exponent negative four."}, {"title": "The pH scale .txt", "text": "Here, to make this positive, I simply multiply both sides by negative one and I brought the negative to this side."}, {"title": "The pH scale .txt", "text": "And that's why this guy is positive."}, {"title": "The pH scale .txt", "text": "So for example, suppose if I had the ten and I had this value, but this was my unknown, I could simply use this to find my exponent."}, {"title": "The pH scale .txt", "text": "That's why logs are convenient whenever you don't know our exponent, but you know the result and you know the base."}, {"title": "The pH scale .txt", "text": "You can use longs to find the exponent."}, {"title": "The pH scale .txt", "text": "That's why logs are used."}, {"title": "The pH scale .txt", "text": "So let's represent this guy as well."}, {"title": "The pH scale .txt", "text": "So this guy ten to negative five is equal to one over 100,000, which is 0.1\nand equivalently on the log scale if you're presented in terms of negative log of base ten of 0.0001, and that equals to five."}, {"title": "The pH scale .txt", "text": "Now notice what happens."}, {"title": "The pH scale .txt", "text": "A decrease of tenfold going from this guy to this guy increases by increment of only one, going from four to five."}, {"title": "The pH scale .txt", "text": "Now, let's represent ten to negative six and ten to negative seven as well."}, {"title": "The pH scale .txt", "text": "Well, we get this result and we get six and seven."}, {"title": "The pH scale .txt", "text": "Now notice this."}, {"title": "The pH scale .txt", "text": "Going from tens of negative four to ten to negative six is a decrease in 100 fold."}, {"title": "The pH scale .txt", "text": "And going from 10th to negative four to ten to negative seven is a decrease in 1000 fold."}, {"title": "The pH scale .txt", "text": "But on a PH scale, on a log scale, it only decreases by an increment of two and an increment of three."}, {"title": "The pH scale .txt", "text": "And that means now, we can graph these guys."}, {"title": "The pH scale .txt", "text": "We can graph PH versus, say, temperature, right?"}, {"title": "The pH scale .txt", "text": "And this will create a very good graph."}, {"title": "The pH scale .txt", "text": "That's exactly why we use PH in the PH scale, just simply because it's a convenient way of converting inconvenient Molar numbers to convenient numbers."}, {"title": "The pH scale .txt", "text": "Okay?"}, {"title": "The pH scale .txt", "text": "Now, one last note about this is that our range for PH can range anywhere from zero to 14, where zero is the smallest possible PH and 14 is the largest possible PH."}, {"title": "The pH scale .txt", "text": "So let's look at this size."}, {"title": "The pH scale .txt", "text": "So at 25 degrees Celsius, we say that a PH of seven is neutral."}, {"title": "The pH scale .txt", "text": "And that's because PH of seven is smack in the middle."}, {"title": "The pH scale .txt", "text": "PH of water is seven because we have just as many H ions as we have hydroxide ions."}, {"title": "The pH scale .txt", "text": "So our PH is right in the middle."}, {"title": "The pH scale .txt", "text": "Remember, this represents acidity, and this represents how basic something is."}, {"title": "The pH scale .txt", "text": "Now, a PH of less than seven represents something that's acidic."}, {"title": "The pH scale .txt", "text": "And that's because as our PH decreases, our concentration of H ions increases."}, {"title": "The pH scale .txt", "text": "Because, look, as we go from seven to four, we go from ten to negative seven to ten to negative four Molar amounts of H plus in the same way that a PH of seven is basic."}, {"title": "The pH scale .txt", "text": "And that's because as we go down or as we go up on the PH scale, we go down, we decrease on the Molar scale."}, {"title": "The pH scale .txt", "text": "Now, if you want to do a problem using this guy using the formula, check out the link below."}, {"title": "Triple bond of Acetylene.txt", "text": "So, in this lecture, we're going to begin a discussion on triple bonds."}, {"title": "Triple bond of Acetylene.txt", "text": "And we're going to build a molecular orbital diagram for the simplest alkyne known as acetylene or ethylene."}, {"title": "Triple bond of Acetylene.txt", "text": "So this compound is composed of two carbon atoms and two H atoms."}, {"title": "Triple bond of Acetylene.txt", "text": "The bonds between the carbon and the H are one SSP hybridized."}, {"title": "Triple bond of Acetylene.txt", "text": "And the bond, a sigma bond between the two carbon atoms is SPSP hybridized."}, {"title": "Triple bond of Acetylene.txt", "text": "Now, these two other bonds are the two Pi bonds, as we'll see in just a second."}, {"title": "Triple bond of Acetylene.txt", "text": "So let's try to build our molecular orbital diagram for this compound using the atomic orbitals of the individual atoms."}, {"title": "Triple bond of Acetylene.txt", "text": "So once again, we have our two H atoms."}, {"title": "Triple bond of Acetylene.txt", "text": "They're in the neutral state."}, {"title": "Triple bond of Acetylene.txt", "text": "So that means they each have one electron each in the one S orbital."}, {"title": "Triple bond of Acetylene.txt", "text": "So here we have the one S orbital of the first H and the one S orbital of the second H. Now, this black dot is simply our electron, the balanced electron, to be specific."}, {"title": "Triple bond of Acetylene.txt", "text": "So now let's take our two carbon atoms."}, {"title": "Triple bond of Acetylene.txt", "text": "So, once again, these guys are all separated."}, {"title": "Triple bond of Acetylene.txt", "text": "They haven't yet combined to form our ethylene compound."}, {"title": "Triple bond of Acetylene.txt", "text": "So here we have one carbon, and here we have the second carbon."}, {"title": "Triple bond of Acetylene.txt", "text": "So two of the orbitals for this carbon are SP hybridized."}, {"title": "Triple bond of Acetylene.txt", "text": "And the same thing goes for this carbon."}, {"title": "Triple bond of Acetylene.txt", "text": "These two orbitals are SP hybridized, shown here as well."}, {"title": "Triple bond of Acetylene.txt", "text": "Now, these two orbitals are pure two p orbitals, and we have one electron in each."}, {"title": "Triple bond of Acetylene.txt", "text": "So altogether, each carbon donates four balance electrons."}, {"title": "Triple bond of Acetylene.txt", "text": "So we have one balanced electron each here and four balance electrons here."}, {"title": "Triple bond of Acetylene.txt", "text": "Each carbon also has two electrons in the one S orbital."}, {"title": "Triple bond of Acetylene.txt", "text": "But that's not shown because the one S orbital does not react."}, {"title": "Triple bond of Acetylene.txt", "text": "So now these two carbons can overlap."}, {"title": "Triple bond of Acetylene.txt", "text": "And to be specific, these SP hybridized orbitals will overlap, and they will each share an electron."}, {"title": "Triple bond of Acetylene.txt", "text": "Likewise, the one S orbital of this H will overlap with the SP orbital of this carbon."}, {"title": "Triple bond of Acetylene.txt", "text": "And likewise, the one orbital here will interact with the SP orbital of the second carbon."}, {"title": "Triple bond of Acetylene.txt", "text": "And we will form our ethnic compound, shown here."}, {"title": "Triple bond of Acetylene.txt", "text": "So this is a molecular orbital diagram of our cyclist alkyne."}, {"title": "Triple bond of Acetylene.txt", "text": "So here we have the SPST hybridized orbital formed from the overlap of each individual SP hybridized orbital."}, {"title": "Triple bond of Acetylene.txt", "text": "And here we have our one SSP on both sides bonds created by the overlap of the one S and SP hybridized orbital of the carbon."}, {"title": "Triple bond of Acetylene.txt", "text": "And notice we still have these pure p orbitals."}, {"title": "Triple bond of Acetylene.txt", "text": "So we have one pure P orbital in the Y direction, y being up, and we have one pure P orbital in the z direction C being coming out of the board."}, {"title": "Triple bond of Acetylene.txt", "text": "And what will happen is there will be an overlap between our two p orbitals that are parallel in the same plane."}, {"title": "Triple bond of Acetylene.txt", "text": "So these two guys, these two orbitals, will interact, and these two orbitals will interact."}, {"title": "Triple bond of Acetylene.txt", "text": "Notice that since these two orbitals are along the y axis and these two orbitals are along the z axis, they're perpendicular to one another."}, {"title": "Triple bond of Acetylene.txt", "text": "And in fact, both of these two appear to the orbitals are perpendicular to these orbitals to the one s SP and to the SPSP."}, {"title": "Triple bond of Acetylene.txt", "text": "In other words, the SP and the SP and the one s and the SP are along the X axis, while these orbitals are along the Y axis and these orbitals are along the Z axis."}, {"title": "Triple bond of Acetylene.txt", "text": "So all of these guys are perpendicular to one another."}, {"title": "Triple bond of Acetylene.txt", "text": "So now let's look at the energy diagram for all these interactions."}, {"title": "Triple bond of Acetylene.txt", "text": "So the One s interacts with the SP to form the one s SP?"}, {"title": "Triple bond of Acetylene.txt", "text": "Molecular orbital."}, {"title": "Triple bond of Acetylene.txt", "text": "In other words, notice that the one s is lower in energy than the SP because the one s has more s character than the SP does."}, {"title": "Triple bond of Acetylene.txt", "text": "And so when they interact, they form two types of molecular orbitals bonding and the antibonding molecular orbitals."}, {"title": "Triple bond of Acetylene.txt", "text": "So since this is higher in energy, electrons will not be found in this rather destabilizing molecular orbital."}, {"title": "Triple bond of Acetylene.txt", "text": "So let's look at the SP and SP interaction."}, {"title": "Triple bond of Acetylene.txt", "text": "So when the carbon and the carbon interact to form our bond, our sigma bond, we have an SP interaction within the atomic orbitals to form our molecular orbitals."}, {"title": "Triple bond of Acetylene.txt", "text": "Or bonding sigma bonding."}, {"title": "Triple bond of Acetylene.txt", "text": "Molecular orbital."}, {"title": "Triple bond of Acetylene.txt", "text": "Likewise."}, {"title": "Triple bond of Acetylene.txt", "text": "Since we input two atomic orbitals, we form two molecular orbitals."}, {"title": "Triple bond of Acetylene.txt", "text": "So we also form the antibiotic SP SP sigma molecular orbital."}, {"title": "Triple bond of Acetylene.txt", "text": "And since this is higher energy no electrons go into here."}, {"title": "Triple bond of Acetylene.txt", "text": "Electrons are only found in the lower stabilizing orbital."}, {"title": "Triple bond of Acetylene.txt", "text": "Now let's look at the two p. Two p interaction."}, {"title": "Triple bond of Acetylene.txt", "text": "In other words, the Pi bonding."}, {"title": "Triple bond of Acetylene.txt", "text": "Remember, these bonds here are all known as Sigma bonds."}, {"title": "Triple bond of Acetylene.txt", "text": "While these bonds are known, the ones in red are known as pi bonds."}, {"title": "Triple bond of Acetylene.txt", "text": "So when the two p and two p interact, which are, by the way, higher in energy than the SP, they form the two p two p pi bonding molecular orbital."}, {"title": "Triple bond of Acetylene.txt", "text": "And the two p two pi antibonding molecular orbital."}, {"title": "Triple bond of Acetylene.txt", "text": "And once again, both electrons go into the lower in energy pi bonding molecular orbital."}, {"title": "Triple bond of Acetylene.txt", "text": "And no electrons go into the two p two pi antibonding molecular orbital."}, {"title": "Triple bond of Acetylene.txt", "text": "So once again, as an overview of the triple Bond within the triple bond, we have a single bond, the covalent Bond, which is SP SP hybridized."}, {"title": "Triple bond of Acetylene.txt", "text": "We have two pi bonds one along the Y direction and one along the Z direction."}, {"title": "Triple bond of Acetylene.txt", "text": "And they're both perpendicular to the Covalent Sigma bond."}, {"title": "Acid Ionization Constant Example .txt", "text": "In this example, we begin with a 0.03 molar of vitonic acid and a PH of 3.5 or 25 degrees Celsius."}, {"title": "Acid Ionization Constant Example .txt", "text": "We want to find the hydroxide concentration as well as the PKA of our botanic acid."}, {"title": "Acid Ionization Constant Example .txt", "text": "Now, we'll find this guy first."}, {"title": "Acid Ionization Constant Example .txt", "text": "So, in step one and three, I find that PKA."}, {"title": "Acid Ionization Constant Example .txt", "text": "And step two, I find the hydroxide filtration."}, {"title": "Acid Ionization Constant Example .txt", "text": "So let's skip to step two."}, {"title": "Acid Ionization Constant Example .txt", "text": "Now, the first thing I do is I use the formula PH plus poh equals 14."}, {"title": "Acid Ionization Constant Example .txt", "text": "Now, if you're not certain about this formula and you don't know where this formula comes from, check out the link below."}, {"title": "Acid Ionization Constant Example .txt", "text": "So, I simply take our PH, plug it in into this number, and we get 14 equals 3.5 plus poh subtract by 3.5\nand I get poh is equal to 10.5."}, {"title": "Acid Ionization Constant Example .txt", "text": "And now I simply apply the formula for poh."}, {"title": "Acid Ionization Constant Example .txt", "text": "So, Poh is equal to 10.5,\nwhich is equal to negative log of the concentration of oh."}, {"title": "Acid Ionization Constant Example .txt", "text": "Now, I convert this log to exponents."}, {"title": "Acid Ionization Constant Example .txt", "text": "By first bringing the negative sign to this side, I see that my base is ten."}, {"title": "Acid Ionization Constant Example .txt", "text": "And I raise that base ten to the negative 10.5 exponent."}, {"title": "Acid Ionization Constant Example .txt", "text": "So, my concentration of hydroxide is equal to ten to the negative 10.5."}, {"title": "Acid Ionization Constant Example .txt", "text": "Plug this into my calculator and get 3.16 times ten to the negative eleven molar."}, {"title": "Acid Ionization Constant Example .txt", "text": "So, this is my concentration of hydroxide."}, {"title": "Acid Ionization Constant Example .txt", "text": "So, I found the first part."}, {"title": "Acid Ionization Constant Example .txt", "text": "Now let's look at a PKA."}, {"title": "Acid Ionization Constant Example .txt", "text": "So, before anything else, we must write the dissociation reaction for our acid."}, {"title": "Acid Ionization Constant Example .txt", "text": "So, our acid in the aqueous state reacts with water and liquid state to form a conjugate base and a conjugate acid."}, {"title": "Acid Ionization Constant Example .txt", "text": "Now, our goal is to find the Ka."}, {"title": "Acid Ionization Constant Example .txt", "text": "And then we can find the PKA by using the lock formula."}, {"title": "Acid Ionization Constant Example .txt", "text": "So, what is Ka?"}, {"title": "Acid Ionization Constant Example .txt", "text": "Well, Ka is the ratio of these guys to this guy."}, {"title": "Acid Ionization Constant Example .txt", "text": "Remember, we don't use the liquid component, so we don't really care about this guy."}, {"title": "Acid Ionization Constant Example .txt", "text": "So we can forget about this guy for now."}, {"title": "Acid Ionization Constant Example .txt", "text": "What we want to find is that equilibrium concentration of this guy, this guy and this guy."}, {"title": "Acid Ionization Constant Example .txt", "text": "Then we plug that in into our equilibrium expression and find our Ka."}, {"title": "Acid Ionization Constant Example .txt", "text": "And then we find the PKA by using logs."}, {"title": "Acid Ionization Constant Example .txt", "text": "So we know that we begin."}, {"title": "Acid Ionization Constant Example .txt", "text": "Our initial condition is 0.3 molar of Betonic acid."}, {"title": "Acid Ionization Constant Example .txt", "text": "So our initial condition is we have 0.3 of this guy, we don't care about this guy, we have none of this guy."}, {"title": "Acid Ionization Constant Example .txt", "text": "And we have a very small amount of this guy."}, {"title": "Acid Ionization Constant Example .txt", "text": "Because remember, in pure water, some water dissociates into HBO plus."}, {"title": "Acid Ionization Constant Example .txt", "text": "And if you're not sure about what I'm talking about, check out the link below."}, {"title": "Acid Ionization Constant Example .txt", "text": "But this amount is so small, it tends to the negative seven molar."}, {"title": "Acid Ionization Constant Example .txt", "text": "And that's very small."}, {"title": "Acid Ionization Constant Example .txt", "text": "And so we could approximate this to be zero."}, {"title": "Acid Ionization Constant Example .txt", "text": "So initially, we have zero of this, zero of this and 0.3\nmolar of our acid."}, {"title": "Acid Ionization Constant Example .txt", "text": "We want to find the equilibrium concentration."}, {"title": "Acid Ionization Constant Example .txt", "text": "So in equilibrium, our PH is 3.5."}, {"title": "Acid Ionization Constant Example .txt", "text": "That means we could use the lock formula to find the concentration of this guy."}, {"title": "Acid Ionization Constant Example .txt", "text": "Now, after we find the concentration of this guy, the concentration of this guy is the same thing."}, {"title": "Acid Ionization Constant Example .txt", "text": "That's because 1 mol and 1 mol, our ratio of this guy to this guy is one to one."}, {"title": "Acid Ionization Constant Example .txt", "text": "So that means whatever the amount and molar of this guy is, this guy is the same."}, {"title": "Acid Ionization Constant Example .txt", "text": "So let's find the concentration of hydronium."}, {"title": "Acid Ionization Constant Example .txt", "text": "So, PH equals 3.5\nto my given information is equal to negative log of the concentration of hydrogen."}, {"title": "Acid Ionization Constant Example .txt", "text": "And that means we have to convert this guy to exponents."}, {"title": "Acid Ionization Constant Example .txt", "text": "So our base is ten."}, {"title": "Acid Ionization Constant Example .txt", "text": "We bring a negative over."}, {"title": "Acid Ionization Constant Example .txt", "text": "We get base ten to the negative 3.5 because this is my exponent."}, {"title": "Acid Ionization Constant Example .txt", "text": "So we get our concentration is equal to ten to negative 3.5."}, {"title": "Acid Ionization Constant Example .txt", "text": "And we get 3.16 times ten to negative four molar."}, {"title": "Acid Ionization Constant Example .txt", "text": "So this is my concentration of hydronium as well as my concentration of this conjugate base."}, {"title": "Acid Ionization Constant Example .txt", "text": "And that's because there's a one to one ratio."}, {"title": "Acid Ionization Constant Example .txt", "text": "And this was a two and this was a one."}, {"title": "Acid Ionization Constant Example .txt", "text": "Then I would have to multiply this guy by two to find this."}, {"title": "Acid Ionization Constant Example .txt", "text": "But since it's one to one, they're equal."}, {"title": "Acid Ionization Constant Example .txt", "text": "Okay, so now we have my equilibrium concentration of my conjugate base and my conjugate acid."}, {"title": "Acid Ionization Constant Example .txt", "text": "And I have to find my equilibrium concentration of my initial acid."}, {"title": "Acid Ionization Constant Example .txt", "text": "So initially at 0.3 and at equilibrium, that means I have to have a little bit less than 0.03\nbecause a little bit of it is dissociated into this guy."}, {"title": "Acid Ionization Constant Example .txt", "text": "But how much less is exactly?"}, {"title": "Acid Ionization Constant Example .txt", "text": "Well, the initial amount of vitonic acid minus final amount of conjugate base."}, {"title": "Acid Ionization Constant Example .txt", "text": "So this guy in molar minus this guy in molar will give me the amount of vitamin acid left over."}, {"title": "Acid Ionization Constant Example .txt", "text": "So 0.3 the amount I began with minus 3.116 times ten to negative four."}, {"title": "Acid Ionization Constant Example .txt", "text": "This guy gives me how much of my vitonic acid is left over at equilibrium or 0.2968 molar."}, {"title": "Acid Ionization Constant Example .txt", "text": "So now I have all my equilibrium concentrations."}, {"title": "Acid Ionization Constant Example .txt", "text": "So I simply write my equilibrium expression."}, {"title": "Acid Ionization Constant Example .txt", "text": "So Ka is equal to the concentration of this guy times the concentration of this guy divided by the concentration of this guy."}, {"title": "Acid Ionization Constant Example .txt", "text": "So, 3.16\ntimes ten to the negative four times 3.16 times ten to negative four divided by 0.2968 gives me 3.36\ntimes ten to negative six."}, {"title": "Acid Ionization Constant Example .txt", "text": "So that's our Ka."}, {"title": "Acid Ionization Constant Example .txt", "text": "But we're not done because we want to find the PKA."}, {"title": "Acid Ionization Constant Example .txt", "text": "So I simply use the log formula."}, {"title": "Acid Ionization Constant Example .txt", "text": "So, PKA gives us negative log of this guy produces 5.47."}, {"title": "Acid Ionization Constant Example .txt", "text": "Actually, I don't know why I wrote that."}, {"title": "Acid Ionization Constant Example .txt", "text": "But this guy should be the 3.36 times tentative negative six."}, {"title": "Degree of Unsaturation.txt", "text": "So let's suppose you're given a certain compound, and let's suppose you know what the molecular formula for that compound is."}, {"title": "Degree of Unsaturation.txt", "text": "Now, if the compound is relatively simple, you can figure out what the molecular structure of that compound is using your molecular formula."}, {"title": "Degree of Unsaturation.txt", "text": "But if the compound is relatively complicated and the molecular formula contains lots of different atoms, then it becomes very difficult at determining what the molecular structure is using only your molecular formula."}, {"title": "Degree of Unsaturation.txt", "text": "Now, one tool that we can use to figure out what the molecular structure is is known as degree of unsaturation."}, {"title": "Degree of Unsaturation.txt", "text": "So degree of unsaturation, given by the Greek letter omega, gives us the total number of pi bonds and or ring structures for that given molecular formula."}, {"title": "Degree of Unsaturation.txt", "text": "And the formula to find degree of unsaturation is given by this guy here."}, {"title": "Degree of Unsaturation.txt", "text": "So two N plus two minus x, and the whole thing divided by two, where N represents your number of carbons and x represents your number of hydrogen atoms."}, {"title": "Degree of Unsaturation.txt", "text": "Now, whenever we're using this formula and we're trying to determine degree bond saturation, we have to follow three important rules."}, {"title": "Degree of Unsaturation.txt", "text": "Rule number one, replace all halogens with hydrogens."}, {"title": "Degree of Unsaturation.txt", "text": "Rule number two, whenever you're given a molecule or compound with oxygens or sulfur, omit the oxygens and sulfur in your formula."}, {"title": "Degree of Unsaturation.txt", "text": "And rule number three, remove nitrogens along with one hydrogen per nitrogen atom."}, {"title": "Degree of Unsaturation.txt", "text": "So let's look at how we can use this rule and how we can use or how we can use this formula and these three rules."}, {"title": "Degree of Unsaturation.txt", "text": "So let's begin with example one."}, {"title": "Degree of Unsaturation.txt", "text": "So, in example one, according to our molecular formula, we have six carbons."}, {"title": "Degree of Unsaturation.txt", "text": "So our M is six, and we have twelve H atoms."}, {"title": "Degree of Unsaturation.txt", "text": "So our x is twelve."}, {"title": "Degree of Unsaturation.txt", "text": "So let's use our formula to find degree of unsaturation for compound one."}, {"title": "Degree of Unsaturation.txt", "text": "So we have two times six plus two."}, {"title": "Degree of Unsaturation.txt", "text": "Put that in parentheses."}, {"title": "Degree of Unsaturation.txt", "text": "Minus twelve divided by two equals."}, {"title": "Degree of Unsaturation.txt", "text": "So, once again, our N is six."}, {"title": "Degree of Unsaturation.txt", "text": "Our x is twelve."}, {"title": "Degree of Unsaturation.txt", "text": "So we get two times 612 plus 214 minus twelve, that's two divided by two."}, {"title": "Degree of Unsaturation.txt", "text": "And that gives us one, because two divided by two gives us one."}, {"title": "Degree of Unsaturation.txt", "text": "So our degree of unsaturation for compound one is one."}, {"title": "Degree of Unsaturation.txt", "text": "That means that we either have one pi bond or we have one ring structure in this molecular compound."}, {"title": "Degree of Unsaturation.txt", "text": "So let's look at example two."}, {"title": "Degree of Unsaturation.txt", "text": "Here we have five carbons and six H atoms."}, {"title": "Degree of Unsaturation.txt", "text": "So, once again, our M is five and x is six."}, {"title": "Degree of Unsaturation.txt", "text": "So two times five plus two."}, {"title": "Degree of Unsaturation.txt", "text": "So that's twelve minus six, that's six divided by two gives us, well, six divided by two gives us three."}, {"title": "Degree of Unsaturation.txt", "text": "So, once again, our number of carbons, N is five."}, {"title": "Degree of Unsaturation.txt", "text": "Two times 510 plus 212 minus six inch atoms."}, {"title": "Degree of Unsaturation.txt", "text": "So that six on top and two on the bottom."}, {"title": "Degree of Unsaturation.txt", "text": "So we have three degrees of unsaturation."}, {"title": "Degree of Unsaturation.txt", "text": "So that means we can either have three pi bonds or we can have two pi bonds and one ring structure."}, {"title": "Degree of Unsaturation.txt", "text": "Or two ring structures and Y pi bond and one Pi bond or three ring structures and zero Pi bonds."}, {"title": "Degree of Unsaturation.txt", "text": "So let's look at example number three."}, {"title": "Degree of Unsaturation.txt", "text": "So here we have five carbons."}, {"title": "Degree of Unsaturation.txt", "text": "So our N is five h or eight h atoms."}, {"title": "Degree of Unsaturation.txt", "text": "But now we have bromine, we have two BRS, we have a halogen."}, {"title": "Degree of Unsaturation.txt", "text": "And that means we have to refer to rule number one, which states replace halogens with hydrogens."}, {"title": "Degree of Unsaturation.txt", "text": "So since we have two halogens, that means we have two more H atoms."}, {"title": "Degree of Unsaturation.txt", "text": "So we have eight plus two, a total of ten H atoms."}, {"title": "Degree of Unsaturation.txt", "text": "So our x is ten."}, {"title": "Degree of Unsaturation.txt", "text": "So two times five plus two, that's twelve minus ten, that's two divided by two gives us or two divided by two gives us one."}, {"title": "Degree of Unsaturation.txt", "text": "So this compound either has one Pi bond or one ring structure."}, {"title": "Degree of Unsaturation.txt", "text": "So let's look at compound number four."}, {"title": "Degree of Unsaturation.txt", "text": "For example four."}, {"title": "Degree of Unsaturation.txt", "text": "So here we have five carbons."}, {"title": "Degree of Unsaturation.txt", "text": "Our N is five."}, {"title": "Degree of Unsaturation.txt", "text": "We have eleven H atoms, but we also have N atoms."}, {"title": "Degree of Unsaturation.txt", "text": "So let's go back to our rules."}, {"title": "Degree of Unsaturation.txt", "text": "According to rule number three, remove nitrogens along with one H.\nSo every time we remove a nitrogen, we remove one H. So that means we no longer have eleven HS, but we have eleven minus three HS."}, {"title": "Degree of Unsaturation.txt", "text": "Because if we remove three ends, we have to remove three H's."}, {"title": "Degree of Unsaturation.txt", "text": "So we have a total of eight H atoms."}, {"title": "Degree of Unsaturation.txt", "text": "So our x is eight."}, {"title": "Degree of Unsaturation.txt", "text": "So our two times five plus two."}, {"title": "Degree of Unsaturation.txt", "text": "So that gives us twelve minus eight."}, {"title": "Degree of Unsaturation.txt", "text": "That gives us four divided by two."}, {"title": "Degree of Unsaturation.txt", "text": "So four divided by two gives us two."}, {"title": "Degree of Unsaturation.txt", "text": "So that means we either have two ring structures, zero Pi bonds, one ring structure, or one Pi bond, or two Pi bonds and zero ring structures."}, {"title": "Degree of Unsaturation.txt", "text": "Let's put an equal sign here."}, {"title": "Degree of Unsaturation.txt", "text": "Example number five."}, {"title": "Degree of Unsaturation.txt", "text": "So in this compound we now have six N. So our carbon number is six."}, {"title": "Degree of Unsaturation.txt", "text": "We have eight HS, but we also have two BRS and three oxygens."}, {"title": "Degree of Unsaturation.txt", "text": "Recall that whenever we see an oxygen or a sulfur, according to rule number two, we do not count them."}, {"title": "Degree of Unsaturation.txt", "text": "We omit them in our calculation."}, {"title": "Degree of Unsaturation.txt", "text": "But since rule number one states that halogens count as hydrogens, we have not eight, but eight plus two."}, {"title": "Degree of Unsaturation.txt", "text": "So ten h atoms."}, {"title": "Degree of Unsaturation.txt", "text": "So our x in this case is ten."}, {"title": "Degree of Unsaturation.txt", "text": "So two times 612 plus two gives us 14 minus ten, that gives us four divided by two."}, {"title": "Degree of Unsaturation.txt", "text": "So four divided by two gives us two."}, {"title": "Degree of Unsaturation.txt", "text": "So once again we have six carbons."}, {"title": "Degree of Unsaturation.txt", "text": "So our N is six."}, {"title": "Degree of Unsaturation.txt", "text": "Two times 612 plus 214 minus ten, because eight plus two is ten."}, {"title": "Degree of Unsaturation.txt", "text": "So 14 minus ten is four divided by two is two."}, {"title": "Degree of Unsaturation.txt", "text": "So that means in this compound we either have two Pi bonds, zero ring structures, one ring structure and y pi bonds, or two ring structures and zero pi bonds."}, {"title": "Degree of Unsaturation.txt", "text": "So let's look at example number six, our last example."}, {"title": "Degree of Unsaturation.txt", "text": "So now we have seven carbons."}, {"title": "Degree of Unsaturation.txt", "text": "So our N is seven."}, {"title": "Degree of Unsaturation.txt", "text": "We have eight H atoms and we have one BR."}, {"title": "Degree of Unsaturation.txt", "text": "So that means we have nine H atoms, but we also have three nitrogens."}, {"title": "Degree of Unsaturation.txt", "text": "So we have to remove those three nitrogens."}, {"title": "Degree of Unsaturation.txt", "text": "So nine minus three is six."}, {"title": "Degree of Unsaturation.txt", "text": "Oxygens don't count, so that means our x is six."}, {"title": "Degree of Unsaturation.txt", "text": "So we have two multiplied by seven, which is 14 plus two."}, {"title": "Degree of Unsaturation.txt", "text": "That gives us 16 minus we said that it was six for x."}, {"title": "Degree of Unsaturation.txt", "text": "So we get 16 minus six divided by two gives us five."}, {"title": "Degree of Unsaturation.txt", "text": "So 16 minus six of ten divided by two gives us five."}, {"title": "Degree of Unsaturation.txt", "text": "So this means we have some combination of pi bonds and ring structures, such that when I add up my ring structures and pi bonds, I get five."}, {"title": "Degree of Unsaturation.txt", "text": "For example, one type of combination is three ring structures and two pi bonds, or zero ring structures and five pi bonds pi bonds."}, {"title": "Degree of Unsaturation.txt", "text": "So, once again, degree of unsaturation gives us the total number of pi bonds in our ring structures in our compound."}, {"title": "Degree of Unsaturation.txt", "text": "And we can use degree of unsaturation to help us figure out the molecular structure of our compound using our molecular formula."}, {"title": "Work.txt", "text": "In the previous video, we discussed one type of energy transfers, namely heat transfers."}, {"title": "Work.txt", "text": "We said that energy could travel from a hot object to a cold object and that three types of heat transfers exist convection, conduction, and radiation."}, {"title": "Work.txt", "text": "Another form of energy transfer is work, and there are only Two types of energy transfers heat and work."}, {"title": "Work.txt", "text": "So if it's not heat, it must be work and vice versa."}, {"title": "Work.txt", "text": "So in this lecture, we're going to focus primarily on work."}, {"title": "Work.txt", "text": "So from a physics perspective, what is work?"}, {"title": "Work.txt", "text": "From a physics perspective, if you want to move a box a distance D, or from a point X to a point Y, you have to exert A force on that box over a distance D.\nAnd assuming the force is constant, you can find the work done by this formula."}, {"title": "Work.txt", "text": "Work equals force times distance travel."}, {"title": "Work.txt", "text": "If the force isn't constant, you have to do a little bit of calculus, and you have to use the integral."}, {"title": "Work.txt", "text": "Okay, now, from a chemistry perspective, what is work?"}, {"title": "Work.txt", "text": "Well, when we're in chemistry, we basically want to work with atoms and molecules, and we say that a single molecule or an atom has some kinetic energy, translational energy."}, {"title": "Work.txt", "text": "And collectively, the translational or kinetic energy of the entire system can do work."}, {"title": "Work.txt", "text": "But now it doesn't do work by acting over some distance."}, {"title": "Work.txt", "text": "It does work by expansion."}, {"title": "Work.txt", "text": "So expansion work is called PD work, and you find the work done by multiplying the pressure when it's constant by the change in volume."}, {"title": "Work.txt", "text": "So this equation only holds when the pressure is constant."}, {"title": "Work.txt", "text": "When the pressure isn't constant, we have to use the integral."}, {"title": "Work.txt", "text": "Okay, so there are many different examples that could be used to describe a chemical work, but for the most part, people use two examples, one with balloons and the other one with pistons."}, {"title": "Work.txt", "text": "Okay, so how balloons expand?"}, {"title": "Work.txt", "text": "Balloons expand because you blow in air."}, {"title": "Work.txt", "text": "In other words, you blow in oxygen molecules, water vapor, you blow in carbon dioxide, you blow in nitrogen molecules, and so on."}, {"title": "Work.txt", "text": "And the increase in the number of molecules increases the system's kinetic energy, collective kinetic energy."}, {"title": "Work.txt", "text": "And that, in turn, pushes on the walls of the balloon."}, {"title": "Work.txt", "text": "And this push exerts a pressure or A force on the outside molecules, the surrounding molecules in the air."}, {"title": "Work.txt", "text": "And this does work on those molecules, expanding the balloon and moving those molecules away."}, {"title": "Work.txt", "text": "Okay?"}, {"title": "Work.txt", "text": "So collectively, the molecules or the atoms within the system, within a stationary system expand by doing work on the surrounding molecules."}, {"title": "Work.txt", "text": "Okay?"}, {"title": "Work.txt", "text": "The same concept works for a piston."}, {"title": "Work.txt", "text": "In a piston, at some constant pressure, you have some molecules floating around within this area, okay?"}, {"title": "Work.txt", "text": "And the atmosphere exerts a force on the piston downward."}, {"title": "Work.txt", "text": "Now, what happens if, for example, you heat the system?"}, {"title": "Work.txt", "text": "If you heat the system, you increase the kinetic energy of the molecules inside here by increasing their speed."}, {"title": "Work.txt", "text": "And this, in turn, will push against the piston."}, {"title": "Work.txt", "text": "It will push against those molecules found in the air here and will do work on them."}, {"title": "Work.txt", "text": "And it will expand the entire system."}, {"title": "Work.txt", "text": "So, once again, the collective kinetic energy of the system inside does work on the outside molecules, the surrounding molecules."}, {"title": "Work.txt", "text": "Okay?"}, {"title": "Work.txt", "text": "And that is how it expands."}, {"title": "Work.txt", "text": "And when force or when pressure is constant, we can find the equation."}, {"title": "Work.txt", "text": "We can find the work done on the surroundings by simply using the equation."}, {"title": "Work.txt", "text": "Work equals volume or change in volume times pressure."}, {"title": "Work.txt", "text": "Okay?"}, {"title": "Work.txt", "text": "Now, how do we come up with this equation?"}, {"title": "Work.txt", "text": "Let's circle this equation that we keep on mentioning."}, {"title": "Work.txt", "text": "Okay, so work equals pressure times change in volume, right?"}, {"title": "Work.txt", "text": "So we start with pressure."}, {"title": "Work.txt", "text": "When we talk about chemistry and chemical systems, we always talk about pressure."}, {"title": "Work.txt", "text": "And pressure is force per unit area, okay?"}, {"title": "Work.txt", "text": "Now what happens if we just multiply this side by A and this side by A?"}, {"title": "Work.txt", "text": "Well, if you multiply this side by A, the A's cancel out."}, {"title": "Work.txt", "text": "We get S. If you multiply this side by A, we get PA."}, {"title": "Work.txt", "text": "Okay?"}, {"title": "Work.txt", "text": "So force is equal to pressure times area."}, {"title": "Work.txt", "text": "Okay?"}, {"title": "Work.txt", "text": "Now what happens if we multiply by distance, both sides by distance?"}, {"title": "Work.txt", "text": "You multiply this side by distance, we get force times distance."}, {"title": "Work.txt", "text": "If you multiply this side by distance, we get pressure times area times distance."}, {"title": "Work.txt", "text": "But remember, that area times distance is simply the volume."}, {"title": "Work.txt", "text": "That is, if we go back to our Piston example and the Piston moves a certain distance, say, D, then this area A times distance D will give us this whole volume here or the change in volume."}, {"title": "Work.txt", "text": "Therefore, pressure times change in volume is equal to work."}, {"title": "Work.txt", "text": "And that's how we derive this equation, from pressure."}, {"title": "Work.txt", "text": "Okay?"}, {"title": "Work.txt", "text": "And that's what work is in a chemical perspective or from a chemical perspective."}, {"title": "Work.txt", "text": "Now let's look at a graph of pressure versus volume, when pressure is constant, okay?"}, {"title": "Work.txt", "text": "What we see is pressure is the y axis, the vertical axis."}, {"title": "Work.txt", "text": "It's constant."}, {"title": "Work.txt", "text": "So it's the same throughout the entire process."}, {"title": "Work.txt", "text": "The volume, however, changes."}, {"title": "Work.txt", "text": "It goes from some lower volume to some higher volume."}, {"title": "Work.txt", "text": "Okay?"}, {"title": "Work.txt", "text": "What the work is, is this."}, {"title": "Work.txt", "text": "The pressure which is constant."}, {"title": "Work.txt", "text": "The pressure is the vertical side, this side."}, {"title": "Work.txt", "text": "So that's pressure times the change in volume v two or V final minus V one, B initial."}, {"title": "Work.txt", "text": "So this side, this is change in volume."}, {"title": "Work.txt", "text": "So this side times this side gives us the work."}, {"title": "Work.txt", "text": "So since this is a rectangle and the area of a rectangle is is side times width, what we see or side times width, what we see is that work is this shade regions here."}, {"title": "Work.txt", "text": "And this is actually work."}, {"title": "Work.txt", "text": "Pressure times change in volume."}, {"title": "Work.txt", "text": "Okay?"}, {"title": "Work.txt", "text": "Now, if we want to find a work when pressure is in constant, we could still do it."}, {"title": "Work.txt", "text": "But then we have to use the integral over some area, okay?"}, {"title": "Work.txt", "text": "We could no longer use this equation because this equation assumes that pressure is constant throughout the experiment."}, {"title": "Work.txt", "text": "But if it's not constant, we have to use calculus and we have to degree."}, {"title": "Internal Energy of Matter .txt", "text": "Today we're going to talk about internal energy."}, {"title": "Internal Energy of Matter .txt", "text": "So what is internal energy?"}, {"title": "Internal Energy of Matter .txt", "text": "Well, internal energy is the collective energy of all the different types of molecules found within a system."}, {"title": "Internal Energy of Matter .txt", "text": "Now, a system can be composed of billions of different molecules."}, {"title": "Internal Energy of Matter .txt", "text": "For simplification purposes, we're going to look at a system with only two diatomic oxygen molecules, moles."}, {"title": "Internal Energy of Matter .txt", "text": "Now, let's look at the types of energies molecules could have."}, {"title": "Internal Energy of Matter .txt", "text": "Well, they can have either kinetic energy or potential energy."}, {"title": "Internal Energy of Matter .txt", "text": "Kinetic energy is the energy due to motion, and it could be subdivided into three different types."}, {"title": "Internal Energy of Matter .txt", "text": "Translational energy is the energy due to velocity."}, {"title": "Internal Energy of Matter .txt", "text": "Now, when a mass moves with a certain velocity, it carries a certain kinetic energy."}, {"title": "Internal Energy of Matter .txt", "text": "And this becomes important in gasses and liquids."}, {"title": "Internal Energy of Matter .txt", "text": "In solids, vibrational energy takes over."}, {"title": "Internal Energy of Matter .txt", "text": "In solids, the molecules don't really move too much."}, {"title": "Internal Energy of Matter .txt", "text": "They vibrate."}, {"title": "Internal Energy of Matter .txt", "text": "And this vibration is created due to repulsion and attraction of protons and electrons."}, {"title": "Internal Energy of Matter .txt", "text": "Now, if we look at this diatomic oxygen molecule, we'll see that this is the case."}, {"title": "Internal Energy of Matter .txt", "text": "This diatomic oxygen molecule is composed of two nuclei."}, {"title": "Internal Energy of Matter .txt", "text": "These two nuclei repel each other because they are positively charged."}, {"title": "Internal Energy of Matter .txt", "text": "So they want to move away from each other."}, {"title": "Internal Energy of Matter .txt", "text": "But notice that each one has an electron cloud around it."}, {"title": "Internal Energy of Matter .txt", "text": "And this guy will attract these guys, and this guy will attract these guys."}, {"title": "Internal Energy of Matter .txt", "text": "So this will create motion, a reverse motion."}, {"title": "Internal Energy of Matter .txt", "text": "Instead of repulsing, they want to attract, okay?"}, {"title": "Internal Energy of Matter .txt", "text": "So this creates repulsion, but they want to attract due to the attraction between this and this and that and that."}, {"title": "Internal Energy of Matter .txt", "text": "Okay, so they create this harmonic vibrational force."}, {"title": "Internal Energy of Matter .txt", "text": "And this is important in solid, okay, rotational."}, {"title": "Internal Energy of Matter .txt", "text": "The first type of kinetic energy, rotational energy is the energy due to torque."}, {"title": "Internal Energy of Matter .txt", "text": "Now, when molecules, for example, the atomic oxygen moves, it moves and rotates."}, {"title": "Internal Energy of Matter .txt", "text": "It rotates this way."}, {"title": "Internal Energy of Matter .txt", "text": "The same way when you throw a Frisbee, the Frisbee rotates and it moves."}, {"title": "Internal Energy of Matter .txt", "text": "And this rotation creates a curved path, okay?"}, {"title": "Internal Energy of Matter .txt", "text": "And this rotation also creates kinetic energy."}, {"title": "Internal Energy of Matter .txt", "text": "Now let's look at the different types of potential energies that exist."}, {"title": "Internal Energy of Matter .txt", "text": "Potential energies are energies due to positional placement in space, three types exist."}, {"title": "Internal Energy of Matter .txt", "text": "Rough mass is the energy due to a stationary mass."}, {"title": "Internal Energy of Matter .txt", "text": "Now, any mass has energy, and Einstein showed this with the equation E equals MC squared."}, {"title": "Internal Energy of Matter .txt", "text": "The larger the mass, the larger the energy."}, {"title": "Internal Energy of Matter .txt", "text": "Electrostatic energy is the energy due to the attraction and repulsion of the protons in the nuclei or the nucleus and the electrons in the electron cloud, okay?"}, {"title": "Internal Energy of Matter .txt", "text": "This creates an electrostatic potential energy."}, {"title": "Internal Energy of Matter .txt", "text": "Intermolecular energy is the energy due to neighboring molecules."}, {"title": "Internal Energy of Matter .txt", "text": "If we go back to our system that's composed of two diatomic oxygen molecules, we see that the protons found on this nucleus will attract the electrons of the neighboring atom."}, {"title": "Internal Energy of Matter .txt", "text": "And the same thing for this one."}, {"title": "Internal Energy of Matter .txt", "text": "The proton here will attract electrons here, and they will create potential energy, okay?"}, {"title": "Internal Energy of Matter .txt", "text": "Now, to find an internal energy of the system, I would literally have to look at every single one of these for this molecule."}, {"title": "Internal Energy of Matter .txt", "text": "Add that up."}, {"title": "Internal Energy of Matter .txt", "text": "I would have to look at the same situation here, take all these, add them up for this one and then I would sum them together."}, {"title": "Internal Energy of Matter .txt", "text": "And that would be my total or my internal energy."}, {"title": "Internal Energy of Matter .txt", "text": "Now, if I had billions of molecules, I would have to do it for every single molecule."}, {"title": "Internal Energy of Matter .txt", "text": "Now, one last thing I want to mention is that internal energy is a state function."}, {"title": "Internal Energy of Matter .txt", "text": "And what that means is simply that eternal energy does not depend on the process or the pathway taken to get to this system."}, {"title": "Internal Energy of Matter .txt", "text": "What it does depend on is the current system at hand and it's also an external property."}, {"title": "Internal Energy of Matter .txt", "text": "And that simply means that with increase in size of the system, internal energy of the system will also increase."}, {"title": "Internal Energy of Matter .txt", "text": "And that's simply because if you increase the number of molecules in a system, there are more kinetic energies and potential energies to sum up and so that internal energy will increase."}, {"title": "Internal Energy of Matter .txt", "text": "And if you want to learn more about this, check out my other video."}, {"title": "Autoionization Example .txt", "text": "In this example, we be given with two solutions."}, {"title": "Autoionization Example .txt", "text": "Our first solution is a seven molar nitric acid solution given at 25 degrees Celsius."}, {"title": "Autoionization Example .txt", "text": "Our second solution is a seven molar sodium hydroxide solution given also at 25 degrees Celsius."}, {"title": "Autoionization Example .txt", "text": "We want to find two things."}, {"title": "Autoionization Example .txt", "text": "First, you want to find the concentration of hydroxide."}, {"title": "Autoionization Example .txt", "text": "Now, seven molar nitric acid solution."}, {"title": "Autoionization Example .txt", "text": "And second, we want to find the concentration of hydronium in our seven molar sodium hydroxide solution."}, {"title": "Autoionization Example .txt", "text": "So, in the first step, we're going to do Part A."}, {"title": "Autoionization Example .txt", "text": "So, first we must write the odor ionization reaction for water."}, {"title": "Autoionization Example .txt", "text": "So two moles of water react to produce 1 mol of conjugate acid and 1 mol of conjugate base."}, {"title": "Autoionization Example .txt", "text": "Now, let's write the equilibrium constants equation or expression for our odorionization reaction."}, {"title": "Autoionization Example .txt", "text": "So, Kw is equal to concentration of hydronium times the concentration of hydroxide."}, {"title": "Autoionization Example .txt", "text": "So we know our Kw."}, {"title": "Autoionization Example .txt", "text": "That's a constant at a 25 degree Celsius, it's ten to negative 14."}, {"title": "Autoionization Example .txt", "text": "Now, we also know this guy, that's seven molar because we're dealing with an acid."}, {"title": "Autoionization Example .txt", "text": "This is seven molar of acid."}, {"title": "Autoionization Example .txt", "text": "And this acid associates into H plus and some other ion."}, {"title": "Autoionization Example .txt", "text": "And this H plus increases the concentration of both this guy and this guy."}, {"title": "Autoionization Example .txt", "text": "And in fact, H and H 30 plus are one and the same."}, {"title": "Autoionization Example .txt", "text": "They're meant to represent the same thing."}, {"title": "Autoionization Example .txt", "text": "So our concentration of hydronium in our solution is seven molar."}, {"title": "Autoionization Example .txt", "text": "So we know Kw and we know this guy."}, {"title": "Autoionization Example .txt", "text": "Now, we could plug it in and find our result."}, {"title": "Autoionization Example .txt", "text": "Now, by the way, if you're confused at this part, or if you're confused about the autoimization of water, check out the link below."}, {"title": "Autoionization Example .txt", "text": "So we basically take our numbers, we plug them in, and we find that 10th of the negative 14 divided by seven gives you 1.43 times ten to negative 15 molar of this guy of seven molar nitric acid solution."}, {"title": "Autoionization Example .txt", "text": "So this means that our concentration of our base, of our hydroxide is very, very small."}, {"title": "Autoionization Example .txt", "text": "And this means this must be a very strong acid or a very acidic solution."}, {"title": "Autoionization Example .txt", "text": "So let's do part two, part B in this section."}, {"title": "Autoionization Example .txt", "text": "So, our sodium hydroxide dissociates into sodium and hydroxide."}, {"title": "Autoionization Example .txt", "text": "So this must be our base."}, {"title": "Autoionization Example .txt", "text": "So our seven molar concentration now refers to the concentration of hydroxide."}, {"title": "Autoionization Example .txt", "text": "So we simply repeat the step kw 10th to negative 14 equal it unknown times seven."}, {"title": "Autoionization Example .txt", "text": "We bring the seven over and we get divided."}, {"title": "Autoionization Example .txt", "text": "And we get 4.1.43 times ten to negative 15 molar of this guy of seven molar sodium hydroxide."}, {"title": "Autoionization Example .txt", "text": "So these two numbers have the same magnitude, but they mean two different things."}, {"title": "Autoionization Example .txt", "text": "In this case, this means the concentration of hydroxide."}, {"title": "Autoionization Example .txt", "text": "That means it's a very small concentration of base."}, {"title": "Autoionization Example .txt", "text": "So this is an acidic solution."}, {"title": "Autoionization Example .txt", "text": "In this case, this is a very small concentration of hydronium."}, {"title": "Autoionization Example .txt", "text": "So this must be a very basic solution."}, {"title": "Buffer Systems .txt", "text": "In this lecture we're going to look at buffer systems or buffer solutions."}, {"title": "Buffer Systems .txt", "text": "Now to begin, let's suppose we have a system of one liter of pure water that has a PH of seven."}, {"title": "Buffer Systems .txt", "text": "Let's examine what happens to our PH when we add a small amount of acid or base to our system."}, {"title": "Buffer Systems .txt", "text": "Well, let's begin with the acid."}, {"title": "Buffer Systems .txt", "text": "Suppose we add zero one mo of HCL to our one liter system."}, {"title": "Buffer Systems .txt", "text": "Let's see the new PH."}, {"title": "Buffer Systems .txt", "text": "Well, the PH is equal to negative log zero one, and that gives us a PH of two."}, {"title": "Buffer Systems .txt", "text": "That means if we add this little hydrochloric acid, our PH drops by five increments."}, {"title": "Buffer Systems .txt", "text": "That's equivalent to a 100,000 fold increase in the hydronium concentration of our mixture."}, {"title": "Buffer Systems .txt", "text": "So now let's add the same amount of sodium hydroxide, a base to our system."}, {"title": "Buffer Systems .txt", "text": "What will be the new PH?"}, {"title": "Buffer Systems .txt", "text": "Well, first we calculate the Poh."}, {"title": "Buffer Systems .txt", "text": "And the Poh is equal to negative log of 0.1,\ngives it two."}, {"title": "Buffer Systems .txt", "text": "Now we subtract two from 14 and we get a PH of twelve."}, {"title": "Buffer Systems .txt", "text": "That means our PH increases by five increments."}, {"title": "Buffer Systems .txt", "text": "That's equivalent to a 100,000 fold increase in the hydroxide concentration."}, {"title": "Buffer Systems .txt", "text": "That's a very big increase in PH."}, {"title": "Buffer Systems .txt", "text": "So the takeaway from this is that adding a small amount of acid or base to pure water will drastically change the PH of water."}, {"title": "Buffer Systems .txt", "text": "Now, if you're confused about how we got this part or this part, check out the link below."}, {"title": "Buffer Systems .txt", "text": "Now Aqueous solutions, unlike pure water, solutions resist changes in PH when we add acid or base."}, {"title": "Buffer Systems .txt", "text": "And that's because aqueous solutions have buffer systems."}, {"title": "Buffer Systems .txt", "text": "And a buffer is simply a chemical system which resists a PH change."}, {"title": "Buffer Systems .txt", "text": "So for example, suppose we had a system of 0.5 molar of acetic acid mixed with 0.5\nmolar of sodium acetate in one liter of water, and this PH and this system's PH was 4.74."}, {"title": "Buffer Systems .txt", "text": "So now what happens to our PH if we add 0.1 molar of hydrochloric acid, as we did in part A?"}, {"title": "Buffer Systems .txt", "text": "Well, now our PH will only decrease from 4.74\nto 4.72."}, {"title": "Buffer Systems .txt", "text": "That's a change of 0.2."}, {"title": "Buffer Systems .txt", "text": "That's a very small change."}, {"title": "Buffer Systems .txt", "text": "Well, that's because this system has a buffer system."}, {"title": "Buffer Systems .txt", "text": "And buffer systems are really important."}, {"title": "Buffer Systems .txt", "text": "For example, our blood is a buffer system."}, {"title": "Buffer Systems .txt", "text": "And if our PH of our blood decreases even slightly, we will suffocate and die."}, {"title": "Buffer Systems .txt", "text": "So these guys are very important."}, {"title": "Buffer Systems .txt", "text": "Now let's see why this happens."}, {"title": "Buffer Systems .txt", "text": "Now, before we look at how they work, let's look at why they work."}, {"title": "Buffer Systems .txt", "text": "What are the few requirements of buffer systems?"}, {"title": "Buffer Systems .txt", "text": "Well, first, we have to have a weak acid and a weak base."}, {"title": "Buffer Systems .txt", "text": "And second, the weak acid cannot react with our weak base, because if they did, our buffer system would be neutralized and we wouldn't have a buffer to work with."}, {"title": "Buffer Systems .txt", "text": "Now, what's one thing that satisfies these two requirements?"}, {"title": "Buffer Systems .txt", "text": "Well, that's a conjugate acid base pair."}, {"title": "Buffer Systems .txt", "text": "Whenever a conjugate acid reacts with a conjugate base, it produces another conjugate acid and base pair for example, acetate ion and acetic acid react to produce acetate ion and acetic acid."}, {"title": "Buffer Systems .txt", "text": "So a conjugate base pair reacts to produce another conjugate base pair."}, {"title": "Buffer Systems .txt", "text": "So nothing is neutralized."}, {"title": "Buffer Systems .txt", "text": "And there are buffer remains unchanged."}, {"title": "Buffer Systems .txt", "text": "So normally, buffers contain equal amounts of conjugate acid as conjugate base."}, {"title": "Buffer Systems .txt", "text": "For example, in this buffer system, we have the same amount of acetic acid as the acetate ion."}, {"title": "Buffer Systems .txt", "text": "Now, some exceptions do exist."}, {"title": "Buffer Systems .txt", "text": "For example, our blood, our blood has much more conjugate base than conjugate acid."}, {"title": "Buffer Systems .txt", "text": "But that's because our body produces many more acidic byproducts than basic byproducts."}, {"title": "Buffer Systems .txt", "text": "And so we need more base to neutralize our acid."}, {"title": "Buffer Systems .txt", "text": "Now, let's see how these buffers work."}, {"title": "Buffer Systems .txt", "text": "So, for example, suppose we have the buffer system above, composed of acetic acid methodate ion."}, {"title": "Buffer Systems .txt", "text": "Now, suppose we add a strong base such as sodium hydroxide to our system."}, {"title": "Buffer Systems .txt", "text": "What will happen?"}, {"title": "Buffer Systems .txt", "text": "Well, this base reacts with our conjugate acid to produce back the conjugate base and water."}, {"title": "Buffer Systems .txt", "text": "So, before this base can affect our system, it's neutralized into a water molecule."}, {"title": "Buffer Systems .txt", "text": "So our PH only changes slightly."}, {"title": "Buffer Systems .txt", "text": "Likewise, let's see what happens when we add acid to our buffer system."}, {"title": "Buffer Systems .txt", "text": "Well, hydrochloric acid first reacts with water, producing hydronium ion and the CL ion."}, {"title": "Buffer Systems .txt", "text": "Next, this acid molecule reacts with our conjugate base, forming water and back our conjugate acid."}, {"title": "Buffer Systems .txt", "text": "So once again, before this acid molecule can affect our solution, decreasing our PH neutralized into water and our conjugate acid."}, {"title": "Buffer Systems .txt", "text": "And that's how buffer systems work."}, {"title": "Atomic Orbitals .txt", "text": "So organic chemistry is essentially the study of covalent bonds."}, {"title": "Atomic Orbitals .txt", "text": "And covalent bonds are formed by the overlap of atomic orbitals."}, {"title": "Atomic Orbitals .txt", "text": "And that means in order to understand what covalent bonds are, we must first understand what atomic orbitals are."}, {"title": "Atomic Orbitals .txt", "text": "So let's begin."}, {"title": "Atomic Orbitals .txt", "text": "So here we have so here we have Boris model."}, {"title": "Atomic Orbitals .txt", "text": "Now, Boris'model is essentially a depiction of the nucleus, the protons found in the nucleus and the electrons found orbiting our nucleus."}, {"title": "Atomic Orbitals .txt", "text": "Now, according to the Boris model, and for this particular atom, our electrons are orbiting in a perfect circle."}, {"title": "Atomic Orbitals .txt", "text": "So for this atom, we have two electrons found in this circle and two electrons found in the outer circular orbit."}, {"title": "Atomic Orbitals .txt", "text": "Now, as you may or may not know, Bored model is actually an inaccurate depiction of our atomic nucleus and electrons."}, {"title": "Atomic Orbitals .txt", "text": "And that's because electrons do not actually occupy these perfect or circular and spherical orbits."}, {"title": "Atomic Orbitals .txt", "text": "Now, Schrodinger described a pathway that our electrons follow using wave equations."}, {"title": "Atomic Orbitals .txt", "text": "So in other words, our electrons follow certain orbits, certain pathways that are not circular."}, {"title": "Atomic Orbitals .txt", "text": "And what this person did is he described the pathways that they take using wave equations."}, {"title": "Atomic Orbitals .txt", "text": "Now, wave equations are simply mathematical representations of the pathways that our electrons do take."}, {"title": "Atomic Orbitals .txt", "text": "And just like any simple equation, we can also solve wave equations for solutions."}, {"title": "Atomic Orbitals .txt", "text": "And the solutions to these wave equations are called wave functions."}, {"title": "Atomic Orbitals .txt", "text": "Now, orbitals are the same thing as wave functions."}, {"title": "Atomic Orbitals .txt", "text": "So orbitals are wave functions."}, {"title": "Atomic Orbitals .txt", "text": "So orbitals are solutions to these wave equations."}, {"title": "Atomic Orbitals .txt", "text": "And since wave equations are simply mathematical representations of the pathway that electrons take, if we solve these wave equations, we can find the probability of an electron being at a certain region in a certain volume."}, {"title": "Atomic Orbitals .txt", "text": "And these probabilities are given by orbitals."}, {"title": "Atomic Orbitals .txt", "text": "So orbitals represent certain shapes or volumes within which our electrons are most likely in."}, {"title": "Atomic Orbitals .txt", "text": "The reason I say most likely is because orbitals are probabilities."}, {"title": "Atomic Orbitals .txt", "text": "Now, before we talk more about orbitals, let's recall what quantum numbers are."}, {"title": "Atomic Orbitals .txt", "text": "Quantum numbers are simply the idea of our electrons."}, {"title": "Atomic Orbitals .txt", "text": "So if we have a unique electron in a given atom, that electron has four unique quantum numbers that are unique to that electron."}, {"title": "Atomic Orbitals .txt", "text": "So we have the principal quantum number, we have the Zimmerfo quantum number, and we have two more quantum numbers."}, {"title": "Atomic Orbitals .txt", "text": "Now, the principal quantum number gives the energy level of that electron."}, {"title": "Atomic Orbitals .txt", "text": "The second quantum number, known as the Zimmerfa quantum number gives or designates the shape of the orbital, and it's represented by the letter L, and it could be 00:12 and so on, zero being the S shape, one being the P shape, two being the D shape."}, {"title": "Atomic Orbitals .txt", "text": "The third quantum number specifies exactly which orbital that our electron is in."}, {"title": "Atomic Orbitals .txt", "text": "And the fourth quantum number gives the spin electron spin of our electron."}, {"title": "Atomic Orbitals .txt", "text": "So we could have either plus one half spin or minus one half spin."}, {"title": "Atomic Orbitals .txt", "text": "So in this lecture, we're only going to deal with the S or the P orbital."}, {"title": "Atomic Orbitals .txt", "text": "So let's begin with the s orbital."}, {"title": "Atomic Orbitals .txt", "text": "So the s orbital, which is one of the solutions to the wave equations, is given by the spherical shape."}, {"title": "Atomic Orbitals .txt", "text": "So this sphere is the s orbital."}, {"title": "Atomic Orbitals .txt", "text": "And what it basically states is that our electron is most likely in this sphere here."}, {"title": "Atomic Orbitals .txt", "text": "Now, of course, as we're talking about probabilities, there is still a probability that our electron will be found outside this spherical shape."}, {"title": "Atomic Orbitals .txt", "text": "But it's very unlikely and that's why we say it's most likely in this orbital."}, {"title": "Atomic Orbitals .txt", "text": "So the p orbital, unlike the s orbital, have a dumbbell like shape or sideways eight."}, {"title": "Atomic Orbitals .txt", "text": "Now we have the PX orbital, we have the PY orbital and the PZ orbital."}, {"title": "Atomic Orbitals .txt", "text": "In other words, if we label this as the x axis, this as the y axis and this as the Z axis."}, {"title": "Atomic Orbitals .txt", "text": "So Z axis is coming out of the board or going into the board."}, {"title": "Atomic Orbitals .txt", "text": "Then we have the following three orbitals."}, {"title": "Atomic Orbitals .txt", "text": "Now, if we take these guys and put them together, we get the overall p orbital and it's given by the following picture, which kind of looks like a flower, a three dimensional flower."}, {"title": "Atomic Orbitals .txt", "text": "Now we have the X orbital."}, {"title": "Atomic Orbitals .txt", "text": "So this guy here, we have the y orbital."}, {"title": "Atomic Orbitals .txt", "text": "So this guy here and we have this z orbital, the PV orbital which is coming out of the board."}, {"title": "Atomic Orbitals .txt", "text": "Now, just like on the XYZ axis, we have the positive side."}, {"title": "Atomic Orbitals .txt", "text": "So Y going this way is positive, x going this way is positive and D going out of the board is positive."}, {"title": "Atomic Orbitals .txt", "text": "We also have the positive sides or positive probabilities of the orbitals."}, {"title": "Atomic Orbitals .txt", "text": "So this green part is the positive and the blue part is the negative."}, {"title": "Atomic Orbitals .txt", "text": "Now, because we're dealing with waves and waves have nodes and anti nodes."}, {"title": "Atomic Orbitals .txt", "text": "These guys will also have nodes and anti nodes."}, {"title": "Atomic Orbitals .txt", "text": "Now the nodes are these guys here."}, {"title": "Atomic Orbitals .txt", "text": "So if you could think of the eight and the eight intersects at this point."}, {"title": "Atomic Orbitals .txt", "text": "This point is the node."}, {"title": "Atomic Orbitals .txt", "text": "And what it basically states is that our electron has a zero probability of being in this place."}, {"title": "Atomic Orbitals .txt", "text": "So the node means zero probability of finding electron at this place."}, {"title": "Atomic Orbitals .txt", "text": "That means we're never going to find an electron here, here or here, or in the cumulative picture."}, {"title": "Atomic Orbitals .txt", "text": "We're never going to find the electron at the origin at the point on this XYZ axis."}, {"title": "Atomic Orbitals .txt", "text": "So why are these guys important?"}, {"title": "Atomic Orbitals .txt", "text": "How can we use these guys to represent pictures of our atoms?"}, {"title": "Atomic Orbitals .txt", "text": "Okay, so let's take an example."}, {"title": "Atomic Orbitals .txt", "text": "Let's take the carbon atom."}, {"title": "Atomic Orbitals .txt", "text": "So carbon, a neutral carbon, has six protons."}, {"title": "Atomic Orbitals .txt", "text": "Hence this subscript six and six electrons."}, {"title": "Atomic Orbitals .txt", "text": "So that means if we were to draw our electron configuration, we would get this depiction."}, {"title": "Atomic Orbitals .txt", "text": "So two electrons go into this one s, two electrons go into this two s, and two electrons go into this picture here."}, {"title": "Atomic Orbitals .txt", "text": "But remember, we have to follow the poly exclusion principle which basically states that a maximum of two electrons can be placed into any orbital."}, {"title": "Atomic Orbitals .txt", "text": "So two electrons can be placed into the s.\nTwo electrons each can be placed into the PX, PY and PZ."}, {"title": "Atomic Orbitals .txt", "text": "So cumulatively, we're going to have a total, a maximum of six electrons that can be placed into this flower shaped p orbital, because this actually includes three separate orbitals."}, {"title": "Atomic Orbitals .txt", "text": "So two can be placed from here into here and into here."}, {"title": "Atomic Orbitals .txt", "text": "Now, also recall Honduras."}, {"title": "Atomic Orbitals .txt", "text": "Hans Rule basically states that before we begin completely filling these orbitals, we first have to place one electron here, one electron here, and one electron here."}, {"title": "Atomic Orbitals .txt", "text": "So we have to go in order."}, {"title": "Atomic Orbitals .txt", "text": "And that's exactly what we do here."}, {"title": "Atomic Orbitals .txt", "text": "One electron is placed into the PX."}, {"title": "Atomic Orbitals .txt", "text": "And one electron is placed into the PY."}, {"title": "Atomic Orbitals .txt", "text": "And that's exactly what we do here."}, {"title": "Atomic Orbitals .txt", "text": "So let's look at what happened."}, {"title": "Atomic Orbitals .txt", "text": "So the electrons are the brown dots."}, {"title": "Atomic Orbitals .txt", "text": "I used brown because we already used blue, and I don't want to confuse you guys further."}, {"title": "Atomic Orbitals .txt", "text": "So the blue or the brown are our electrons."}, {"title": "Atomic Orbitals .txt", "text": "So the one that's orbital I did not depict."}, {"title": "Atomic Orbitals .txt", "text": "And that's because the one that's orbital is simply a smaller black sphere found within this two s sphere."}, {"title": "Atomic Orbitals .txt", "text": "This black sphere."}, {"title": "Atomic Orbitals .txt", "text": "Here is the two s sphere."}, {"title": "Atomic Orbitals .txt", "text": "So let's imagine that we took our two electrons and placed it into our one s. And now we're taking out two electrons and place it into the two s. The two s is this black sphere here."}, {"title": "Atomic Orbitals .txt", "text": "And I took two electrons and placed it into the black sphere, as shown here."}, {"title": "Atomic Orbitals .txt", "text": "Now, I have one electron that I place into the X."}, {"title": "Atomic Orbitals .txt", "text": "So the green region and one electron that I placed into the Y region."}, {"title": "Atomic Orbitals .txt", "text": "So the Y orbital or the green part of the Y orbital?"}, {"title": "Atomic Orbitals .txt", "text": "And that's the picture."}, {"title": "Atomic Orbitals .txt", "text": "Or the picture using atomic orbitals of our carbon."}, {"title": "Atomic Orbitals .txt", "text": "Now."}, {"title": "Atomic Orbitals .txt", "text": "We'll see in later lectures how when these guys interact with other orbitals, with other atoms, they form something called covalent bonds."}, {"title": "Atomic Orbitals .txt", "text": "Now let's look at neon."}, {"title": "Atomic Orbitals .txt", "text": "Now."}, {"title": "Atomic Orbitals .txt", "text": "Neon has ten protons and ten electrons."}, {"title": "Atomic Orbitals .txt", "text": "In fact, it has a perfect electron configuration."}, {"title": "Atomic Orbitals .txt", "text": "It's a noble gas."}, {"title": "Atomic Orbitals .txt", "text": "So all the electrons, all the atomic orbitals should be filled."}, {"title": "Atomic Orbitals .txt", "text": "So let's look at our electron configuration."}, {"title": "Atomic Orbitals .txt", "text": "So we have one s, two, two s, two, two PX, two, two p y two and two PZ, two."}, {"title": "Atomic Orbitals .txt", "text": "So once again, two electrons go into the one s which isn't shown."}, {"title": "Atomic Orbitals .txt", "text": "Two electrons go into the two s, which is shown."}, {"title": "Atomic Orbitals .txt", "text": "And here we have two electrons."}, {"title": "Atomic Orbitals .txt", "text": "Two electrons go into our x orbital, two electrons go into the two p y orbital and two electrons go into the two PZ orbital."}, {"title": "Atomic Orbitals .txt", "text": "So all the Orbitals all the Green Orbitals are filled."}, {"title": "Atomic Orbitals .txt", "text": "And so this is our atomic orbital representation of our neon, in which it has a perfect election configuration."}, {"title": "Atomic Orbitals .txt", "text": "All our orbitals are filled."}, {"title": "Introduction to Resonance Forms .txt", "text": "In this lecture, I let's talk about resonance."}, {"title": "Introduction to Resonance Forms .txt", "text": "Now, before we get into resonance, let's recall what lewis that structure is."}, {"title": "Introduction to Resonance Forms .txt", "text": "A lewis structure is simply an electronic configuration of our atoms, our molecules and compounds."}, {"title": "Introduction to Resonance Forms .txt", "text": "So let's begin by using formaldehyde."}, {"title": "Introduction to Resonance Forms .txt", "text": "So we're going to have this compound that's compared composed of one carbon, one oxygen and two h atoms."}, {"title": "Introduction to Resonance Forms .txt", "text": "Now we're going to draw the lewis down structure for our formaldehyde."}, {"title": "Introduction to Resonance Forms .txt", "text": "So our first step is to count the number of balanced electrons."}, {"title": "Introduction to Resonance Forms .txt", "text": "Balanced electrons, once again, of those electrons that come from the outermost shells of our atoms."}, {"title": "Introduction to Resonance Forms .txt", "text": "So oxygen has six valence electrons, carbon has four valence electrons, and h has one each."}, {"title": "Introduction to Resonance Forms .txt", "text": "We have two h, and so two valence electrons come from our two HS."}, {"title": "Introduction to Resonance Forms .txt", "text": "So we have a total of twelve balanced electrons."}, {"title": "Introduction to Resonance Forms .txt", "text": "So let's begin drawing our loose dot structure."}, {"title": "Introduction to Resonance Forms .txt", "text": "So we have carbon, two h's and 10."}, {"title": "Introduction to Resonance Forms .txt", "text": "So let's begin by first drawing our sigma, or Covalent bonds."}, {"title": "Introduction to Resonance Forms .txt", "text": "So we have two bonds between the chas, and we have one bond between the oxygen."}, {"title": "Introduction to Resonance Forms .txt", "text": "So here's our Covalent sigma bond, covalent sigma bond, and Covalent sigma bond."}, {"title": "Introduction to Resonance Forms .txt", "text": "So so far, we have used up six balance electrons."}, {"title": "Introduction to Resonance Forms .txt", "text": "We have six more balanced electrons that we can use."}, {"title": "Introduction to Resonance Forms .txt", "text": "Notice that carbon and oxygen both can develop double bonds."}, {"title": "Introduction to Resonance Forms .txt", "text": "So let's create a double bond between carbon and oxygen."}, {"title": "Introduction to Resonance Forms .txt", "text": "So we place two electrons and we create a pi bond."}, {"title": "Introduction to Resonance Forms .txt", "text": "So now we have four more balanced electrons we can place, and we place them around the oxygen like so."}, {"title": "Introduction to Resonance Forms .txt", "text": "Now, because oxygen has 123456, carbon has 1234, and h has one each, this is a neutral lewis structure, lewis form."}, {"title": "Introduction to Resonance Forms .txt", "text": "Now, the following problem arises."}, {"title": "Introduction to Resonance Forms .txt", "text": "Now, this is not the only lewis structure that exists."}, {"title": "Introduction to Resonance Forms .txt", "text": "Others exist."}, {"title": "Introduction to Resonance Forms .txt", "text": "And in fact, here's one other one."}, {"title": "Introduction to Resonance Forms .txt", "text": "Instead of creating that pi bond, by placing those two balanced electrons into our pipeline here, we could have simply placed those two electrons on oxygen, and that would create another lewis dot structure."}, {"title": "Introduction to Resonance Forms .txt", "text": "However, this structure has a negative charge on oxygen and a plus charge on the carbon, because we only have one, two, three bonds here, and we have 123-4567 electrons on the oxygen."}, {"title": "Introduction to Resonance Forms .txt", "text": "So notice the following."}, {"title": "Introduction to Resonance Forms .txt", "text": "We have two different lewis structures for formaldehyde, and in fact, this idea, this concept is called resonance."}, {"title": "Introduction to Resonance Forms .txt", "text": "And these structures, lewis dot structures, are called resonant forms."}, {"title": "Introduction to Resonance Forms .txt", "text": "So let's define resonant forms."}, {"title": "Introduction to Resonance Forms .txt", "text": "Resonant forms are the different combination of the possible lewis dot structures for our compounds."}, {"title": "Introduction to Resonance Forms .txt", "text": "Now, whenever we draw resonant forms, the following two things have to always be kept in mind."}, {"title": "Introduction to Resonance Forms .txt", "text": "The first one is, since lewis structures are electronic configurations, we only move electrons and we never move any atoms."}, {"title": "Introduction to Resonance Forms .txt", "text": "Now, notice what this arrow represents."}, {"title": "Introduction to Resonance Forms .txt", "text": "This arrow is known as arrow formulasm."}, {"title": "Introduction to Resonance Forms .txt", "text": "A double headed arrow simply means two electrons are being moved."}, {"title": "Introduction to Resonance Forms .txt", "text": "So in this case, I have two electrons moving from my pi bond, and they move on to one of the orbitals on the oxygen."}, {"title": "Introduction to Resonance Forms .txt", "text": "And now I no longer have this because these electrons have moved here."}, {"title": "Introduction to Resonance Forms .txt", "text": "So this is, once again, this arrow signifies movement of electrons and not movement of atoms."}, {"title": "Introduction to Resonance Forms .txt", "text": "In other words, if I draw this molecule or this compound where I took this atom and placed the atom onto one of the orbitals here, so now there's a bond, a sigma bond between oxygen, carbon."}, {"title": "Introduction to Resonance Forms .txt", "text": "This is not a resonant form."}, {"title": "Introduction to Resonance Forms .txt", "text": "This is not a lewis dot structure for formaldehyde."}, {"title": "Introduction to Resonance Forms .txt", "text": "In fact, this is not even formaldehyde."}, {"title": "Introduction to Resonance Forms .txt", "text": "It's another molecule."}, {"title": "Introduction to Resonance Forms .txt", "text": "It's another compound altogether."}, {"title": "Introduction to Resonance Forms .txt", "text": "So, once again, in resonant forms, there's only movement of electrons, never movement of atoms."}, {"title": "Introduction to Resonance Forms .txt", "text": "Notice another important point that we'll talk about in detail."}, {"title": "Introduction to Resonance Forms .txt", "text": "In just a moment."}, {"title": "Introduction to Resonance Forms .txt", "text": "There is a double headed arrow, like so, and this represents resonant forms, okay?"}, {"title": "Introduction to Resonance Forms .txt", "text": "And we'll see why this is different than equilibrium arrows."}, {"title": "Introduction to Resonance Forms .txt", "text": "In just a second, let's look at Nitromethane."}, {"title": "Introduction to Resonance Forms .txt", "text": "We're going to do a second example in which we're going to draw the resonant forms."}, {"title": "Introduction to Resonance Forms .txt", "text": "So Nitromethane has one N, two O's, one C and three H's."}, {"title": "Introduction to Resonance Forms .txt", "text": "So in order to draw our loose dot structures, let's count the balanced electrons."}, {"title": "Introduction to Resonance Forms .txt", "text": "So we have three balanced electrons from H.\nWe have four balanced electrons from our carbon."}, {"title": "Introduction to Resonance Forms .txt", "text": "So we have and that means we have five balanced electrons coming from N, and we have two OS."}, {"title": "Introduction to Resonance Forms .txt", "text": "That means we have twelve electrons, balanced electrons coming from oxygen."}, {"title": "Introduction to Resonance Forms .txt", "text": "So altogether, we should have a total of 24 balance electrons, right?"}, {"title": "Introduction to Resonance Forms .txt", "text": "Twelve plus five plus four plus three should give us twelve."}, {"title": "Introduction to Resonance Forms .txt", "text": "So let's begin."}, {"title": "Introduction to Resonance Forms .txt", "text": "We draw our carbon, our H atoms, three H atoms around carbon."}, {"title": "Introduction to Resonance Forms .txt", "text": "Then we draw our end right next to our carbon."}, {"title": "Introduction to Resonance Forms .txt", "text": "And then two o's, like so."}, {"title": "Introduction to Resonance Forms .txt", "text": "We start by creating sigma bonds or covalent bonds."}, {"title": "Introduction to Resonance Forms .txt", "text": "One bond here, a bond here, a bond here between the HS, a fourth bond between the carbon and end."}, {"title": "Introduction to Resonance Forms .txt", "text": "So all the orbitals here are filled."}, {"title": "Introduction to Resonance Forms .txt", "text": "Now we create a bond between sigma bond between o and this o here."}, {"title": "Introduction to Resonance Forms .txt", "text": "Now we have 123-45-6789 711, twelve valve electrons left over."}, {"title": "Introduction to Resonance Forms .txt", "text": "So we create this pi bond here."}, {"title": "Introduction to Resonance Forms .txt", "text": "We place two electrons onto our oxygen, like we did here, and three pairs of electrons here."}, {"title": "Introduction to Resonance Forms .txt", "text": "So that means this guy has a negative charge, like this one has here."}, {"title": "Introduction to Resonance Forms .txt", "text": "This N has a positive charge because N likes to have five electrons."}, {"title": "Introduction to Resonance Forms .txt", "text": "It only has four electrons here, and this has six."}, {"title": "Introduction to Resonance Forms .txt", "text": "So it's neutral."}, {"title": "Introduction to Resonance Forms .txt", "text": "So a plus charge and a minus charge creates a net charge of zero."}, {"title": "Introduction to Resonance Forms .txt", "text": "And this does have a net charge of zero."}, {"title": "Introduction to Resonance Forms .txt", "text": "Now, this isn't the only lewis dot structure."}, {"title": "Introduction to Resonance Forms .txt", "text": "If we move two electrons here and we take these two electrons and create a double bond here, we have the following a distant lewis structure."}, {"title": "Introduction to Resonance Forms .txt", "text": "Basically, these guys flip."}, {"title": "Introduction to Resonance Forms .txt", "text": "Now we have a negative charge here."}, {"title": "Introduction to Resonance Forms .txt", "text": "We still have a positive charge here, and we have a neutral charge here."}, {"title": "Introduction to Resonance Forms .txt", "text": "So once again, we have a combination of Lewis structures."}, {"title": "Introduction to Resonance Forms .txt", "text": "And these guys are known as resonance forms."}, {"title": "Introduction to Resonance Forms .txt", "text": "And the entire concept is known as resonance."}, {"title": "Introduction to Resonance Forms .txt", "text": "Now notice other structures exist."}, {"title": "Introduction to Resonance Forms .txt", "text": "We could have simply taken this double bond, placed in here and created a plus two charge, a minus two charge, and a minus two charge."}, {"title": "Introduction to Resonance Forms .txt", "text": "So more Lewis structures do exist."}, {"title": "Introduction to Resonance Forms .txt", "text": "And now we come to the most important point about resonant forms nitromethane."}, {"title": "Introduction to Resonance Forms .txt", "text": "This compound does not spend half of its time as one resonant form and half of its time as the other."}, {"title": "Introduction to Resonance Forms .txt", "text": "It is a combination of the two."}, {"title": "Introduction to Resonance Forms .txt", "text": "In other words, this arrow does not mean it's an equilibrium."}, {"title": "Introduction to Resonance Forms .txt", "text": "In other words, our nitromethane doesn't spend half the time as this compound, and then it converts to this compound."}, {"title": "Introduction to Resonance Forms .txt", "text": "The entire nitromethane is a combination of these two molecules."}, {"title": "Introduction to Resonance Forms .txt", "text": "Its actual structure is somewhere in the middle of these two resonant forms."}, {"title": "Introduction to Resonance Forms .txt", "text": "And let's look at the following important observation."}, {"title": "Introduction to Resonance Forms .txt", "text": "So let's suppose we have some compound X and it occur and it reacts in some way, and it converts to a completely different molecule, different compound where the atoms have moved."}, {"title": "Introduction to Resonance Forms .txt", "text": "And this is why."}, {"title": "Introduction to Resonance Forms .txt", "text": "Now let's wait until equilibrium has been achieved."}, {"title": "Introduction to Resonance Forms .txt", "text": "So the arrows, the rates going forward and reverse are the same."}, {"title": "Introduction to Resonance Forms .txt", "text": "Now notice that these two arrows are different than this arrow."}, {"title": "Introduction to Resonance Forms .txt", "text": "Now let's suppose we have some compound A and B, which are resonance forms."}, {"title": "Introduction to Resonance Forms .txt", "text": "Now, this once again, does not mean that A converts to B and then B converts to A."}, {"title": "Introduction to Resonance Forms .txt", "text": "Right?"}, {"title": "Introduction to Resonance Forms .txt", "text": "What this means is that the actual form of this molecule is a combination of the two."}, {"title": "Introduction to Resonance Forms .txt", "text": "It's somewhere in between."}, {"title": "Introduction to Resonance Forms .txt", "text": "Our actual molecule that this resin forms represents is an A, nor is it D. It's somewhere in between."}, {"title": "Introduction to Resonance Forms .txt", "text": "And let's call it C. Okay, so this is equivalent to some molecule C, which is a combination of these two molecules."}, {"title": "Introduction to Resonance Forms .txt", "text": "And this arrow does not mean equilibrium."}, {"title": "Introduction to Resonance Forms .txt", "text": "Our molecules here aren't at equilibrium."}, {"title": "Introduction to Resonance Forms .txt", "text": "They're not converting from this form to that form at a dad form to this form."}, {"title": "Introduction to Resonance Forms .txt", "text": "And the same thing here."}, {"title": "Introduction to Resonance Forms .txt", "text": "What's actually happening is the actual molecules are somewhere in between of these two structures."}, {"title": "Introduction to Resonance Forms .txt", "text": "And that's what resonant forms are."}, {"title": "Molecular Orbital Formation Example .txt", "text": "So thus far we have combined a one S orbital and a one S orbital."}, {"title": "Molecular Orbital Formation Example .txt", "text": "And we've also combined a one S with a two P. In this lecture, we're going to combine a two p with a two P to four molecular orbitals."}, {"title": "Molecular Orbital Formation Example .txt", "text": "Now, the first thing we have to realize is that there are at least two different ways that we can orient our two p orbitals."}, {"title": "Molecular Orbital Formation Example .txt", "text": "In part A, we have a parallel orientation."}, {"title": "Molecular Orbital Formation Example .txt", "text": "In other words, our two p orbitals are simply parallel to one another."}, {"title": "Molecular Orbital Formation Example .txt", "text": "In Part B, we have an orthogonal or perpendicular orientation in which our one two p orbital is perpendicular to our second two p orbital."}, {"title": "Molecular Orbital Formation Example .txt", "text": "So let's see which one of these forms molecular orbitals."}, {"title": "Molecular Orbital Formation Example .txt", "text": "So let's begin with part B."}, {"title": "Molecular Orbital Formation Example .txt", "text": "In Part B, we have two ways that we can orient or combine them."}, {"title": "Molecular Orbital Formation Example .txt", "text": "We can either combine the positive of this with the positive of this, or we can combine the positive orbital here and the negative orbital here."}, {"title": "Molecular Orbital Formation Example .txt", "text": "Negative simply means we flip the signs."}, {"title": "Molecular Orbital Formation Example .txt", "text": "In other words, this green is the positive, this green is the negative."}, {"title": "Molecular Orbital Formation Example .txt", "text": "So let's begin by adding or by combining the positive two p and the positive to P. We get the following orientation."}, {"title": "Molecular Orbital Formation Example .txt", "text": "Now notice in this orientation we have the positive interacting in a bonding way with the positive and so that forms a bond."}, {"title": "Molecular Orbital Formation Example .txt", "text": "And here we have an anti bonding interaction because the negative of this two p orbital interacts with the positive section of this two p orbital."}, {"title": "Molecular Orbital Formation Example .txt", "text": "So we have bonding and antibounding."}, {"title": "Molecular Orbital Formation Example .txt", "text": "So let's look at the negative."}, {"title": "Molecular Orbital Formation Example .txt", "text": "Or simply we're combining two p positive and two p negative."}, {"title": "Molecular Orbital Formation Example .txt", "text": "That means this becomes blue and this becomes green."}, {"title": "Molecular Orbital Formation Example .txt", "text": "So we have this orientation."}, {"title": "Molecular Orbital Formation Example .txt", "text": "Once again we have a negative interacting with a negative."}, {"title": "Molecular Orbital Formation Example .txt", "text": "So that means we get a bonding orientation and we have positive interacting with a negative to produce antibonding."}, {"title": "Molecular Orbital Formation Example .txt", "text": "So that means because we have bonding and antibonding, we have no net interaction."}, {"title": "Molecular Orbital Formation Example .txt", "text": "In other words, no net interaction because the bonding and the antibonding exactly cancel out."}, {"title": "Molecular Orbital Formation Example .txt", "text": "So this type of orthogonal orientation does not work."}, {"title": "Molecular Orbital Formation Example .txt", "text": "It does not create molecular orbitals."}, {"title": "Molecular Orbital Formation Example .txt", "text": "So let's go to the parallel."}, {"title": "Molecular Orbital Formation Example .txt", "text": "So once again, in the parallel combination we have two different waves that we can combine."}, {"title": "Molecular Orbital Formation Example .txt", "text": "Remember, we're inputting two atomic orbitals, so we should get back two molecular orbitals."}, {"title": "Molecular Orbital Formation Example .txt", "text": "So let's go this way first."}, {"title": "Molecular Orbital Formation Example .txt", "text": "In other words, we're combining a two p positive and a two p positive."}, {"title": "Molecular Orbital Formation Example .txt", "text": "So we get this orientation."}, {"title": "Molecular Orbital Formation Example .txt", "text": "Notice we have positive interacting with a positive and negative interacting with a negative."}, {"title": "Molecular Orbital Formation Example .txt", "text": "So we have bonding interactions."}, {"title": "Molecular Orbital Formation Example .txt", "text": "Likewise, if we combine positive two p and a negative two p, we switch these guys."}, {"title": "Molecular Orbital Formation Example .txt", "text": "So this becomes a negative blue and this becomes a positive green and we have this orientation."}, {"title": "Molecular Orbital Formation Example .txt", "text": "In this orientation we have positive and negative."}, {"title": "Molecular Orbital Formation Example .txt", "text": "So we have antiboming and antiboding."}, {"title": "Molecular Orbital Formation Example .txt", "text": "So there exists a notal plane smacked between these two guys."}, {"title": "Molecular Orbital Formation Example .txt", "text": "Right in the middle."}, {"title": "Molecular Orbital Formation Example .txt", "text": "So that means there's no electron density here."}, {"title": "Molecular Orbital Formation Example .txt", "text": "So electrons can't be found on this node or nodal plane."}, {"title": "Molecular Orbital Formation Example .txt", "text": "So this, in fact, creates this type of parallel orientation creates two molecular orbitals."}, {"title": "Molecular Orbital Formation Example .txt", "text": "One bonding and one anti bonding."}, {"title": "Molecular Orbital Formation Example .txt", "text": "So let's draw our energy diagram once again."}, {"title": "Molecular Orbital Formation Example .txt", "text": "Going up."}, {"title": "Molecular Orbital Formation Example .txt", "text": "Our energy increases."}, {"title": "Molecular Orbital Formation Example .txt", "text": "Going down."}, {"title": "Molecular Orbital Formation Example .txt", "text": "Our energy decreases."}, {"title": "Molecular Orbital Formation Example .txt", "text": "So since our two p orbitals are exactly identical, that means they're on the same energy level."}, {"title": "Molecular Orbital Formation Example .txt", "text": "So they're on the same level here."}, {"title": "Molecular Orbital Formation Example .txt", "text": "Likewise, because they're identical."}, {"title": "Molecular Orbital Formation Example .txt", "text": "They each have one electron."}, {"title": "Molecular Orbital Formation Example .txt", "text": "Now these two electrons will want to go in this orbital."}, {"title": "Molecular Orbital Formation Example .txt", "text": "Or in that orbital."}, {"title": "Molecular Orbital Formation Example .txt", "text": "Well, probably this one."}, {"title": "Molecular Orbital Formation Example .txt", "text": "And that's because this one is more stabilizing."}, {"title": "Molecular Orbital Formation Example .txt", "text": "It's stabilizing because it's lower in energy."}, {"title": "Molecular Orbital Formation Example .txt", "text": "And nature likes that."}, {"title": "Molecular Orbital Formation Example .txt", "text": "Nature creates a system in which the energy is lower than before."}, {"title": "Molecular Orbital Formation Example .txt", "text": "And so our electrons will combine to form our bonding molecular orbital."}, {"title": "Molecular Orbital Formation Example .txt", "text": "And notice that the spins are different."}, {"title": "Molecular Orbital Formation Example .txt", "text": "They're Opposites."}, {"title": "Molecular Orbital Formation Example .txt", "text": "And this fact is due the pole exclusion principle that states that any orbital has the maximum two electrons and these two electrons have opposite spins."}, {"title": "Molecular Orbital Formation Example .txt", "text": "Now notice that electrons can still go into this orbital, right?"}, {"title": "Molecular Orbital Formation Example .txt", "text": "But they don't want to."}, {"title": "Molecular Orbital Formation Example .txt", "text": "And so that's why you won't find electrons there."}, {"title": "Molecular Orbital Formation Example .txt", "text": "If the electrons do somehow end up in this orbital, this orbital will create a destabilizing effect."}, {"title": "Molecular Orbital Formation Example .txt", "text": "And that means the nuclei will repel one another and will try to break that covalent bond."}, {"title": "Molecular Orbital Formation Example .txt", "text": "So that's exactly why electrons don't like to be in this antibonding orbital."}, {"title": "Molecular Orbital Formation Example .txt", "text": "Because antibonding orbitals destabilize the bonds."}, {"title": "Molecular Orbital Formation Example .txt", "text": "Because the energy is higher than both the beginning atomic IP orbitals and the final bonding molecular orbital."}, {"title": "Introduction to Entropy.txt", "text": "I will talk to you about the concept of entropy."}, {"title": "Introduction to Entropy.txt", "text": "So what is entropy?"}, {"title": "Introduction to Entropy.txt", "text": "Well, the most basic definition of entropy is that entropy is the measure of a disorder."}, {"title": "Introduction to Entropy.txt", "text": "Every system the best and a very good definition because it's kind of vague and you can't quantify with that definition."}, {"title": "Introduction to Entropy.txt", "text": "You can't use numbers."}, {"title": "Introduction to Entropy.txt", "text": "So let's explore the concept of entropy using public probability, and maybe we can come up with a better definition using probability."}, {"title": "Introduction to Entropy.txt", "text": "Okay, so let's look at this system here."}, {"title": "Introduction to Entropy.txt", "text": "This system is composed of two containers connected by a bridge, and within the container, there are four different molecules."}, {"title": "Introduction to Entropy.txt", "text": "And these molecules are allowed to diffuse from one side to the other side."}, {"title": "Introduction to Entropy.txt", "text": "So let's see what's the most probable situation that we can get."}, {"title": "Introduction to Entropy.txt", "text": "Okay, so what's the likelihood that we're going to get four different molecules all on the left side?"}, {"title": "Introduction to Entropy.txt", "text": "Well, this thing could only occur one time, or there's one way that this can occur."}, {"title": "Introduction to Entropy.txt", "text": "So let's look at this side."}, {"title": "Introduction to Entropy.txt", "text": "What's the likelihood that you get two different molecules on the left side of the container or on the left container?"}, {"title": "Introduction to Entropy.txt", "text": "Okay, well, there are six different ways that this can occur."}, {"title": "Introduction to Entropy.txt", "text": "And this means this type of situation is six times as probable."}, {"title": "Introduction to Entropy.txt", "text": "That basically means that if you take a snapshot at any given time of this system, that this snapshot of this picture is more or six times more likely to occur."}, {"title": "Introduction to Entropy.txt", "text": "So now we can come up with a better definition of entropy using probability."}, {"title": "Introduction to Entropy.txt", "text": "Entropy is the tendency of a system to take its most probable form."}, {"title": "Introduction to Entropy.txt", "text": "So in the situation or in the system we have here, what's the most probable form?"}, {"title": "Introduction to Entropy.txt", "text": "Well, it's clear that this one."}, {"title": "Introduction to Entropy.txt", "text": "It must be this one."}, {"title": "Introduction to Entropy.txt", "text": "Okay, now you could imagine this is only with four molecules."}, {"title": "Introduction to Entropy.txt", "text": "You could imagine how unlikely this becomes when we get millions and billions of different molecules."}, {"title": "Introduction to Entropy.txt", "text": "Okay, this becomes much more likely with greater amount of molecules."}, {"title": "Introduction to Entropy.txt", "text": "Now let's explore the relationship between the second law of thermodynamics and entropy."}, {"title": "Introduction to Entropy.txt", "text": "In another video recently, the second law of thermodynamics basically states that heat cannot be completely converted into work."}, {"title": "Introduction to Entropy.txt", "text": "Here we will see a slightly different definition of the second law of thermodynamics."}, {"title": "Introduction to Entropy.txt", "text": "So let's explore these two isolated systems that are the same size, that have the same number of molecules and the same type of molecules."}, {"title": "Introduction to Entropy.txt", "text": "Which one do you think is more probable to occur?"}, {"title": "Introduction to Entropy.txt", "text": "Well, let's find out."}, {"title": "Introduction to Entropy.txt", "text": "Let's use entropy to find out."}, {"title": "Introduction to Entropy.txt", "text": "Okay, well, in this system, the molecules seem to be scattered as far away from each other as possible."}, {"title": "Introduction to Entropy.txt", "text": "In this system, they're very structured."}, {"title": "Introduction to Entropy.txt", "text": "They're in one ball."}, {"title": "Introduction to Entropy.txt", "text": "Okay, so let's see which ones are more probable."}, {"title": "Introduction to Entropy.txt", "text": "So in this system, you have bunch of nuclei, positively charged nuclei close to each other."}, {"title": "Introduction to Entropy.txt", "text": "Now, positive charges repel."}, {"title": "Introduction to Entropy.txt", "text": "And so these guys are going to want to naturally move away from each other, as far away from each other as possible."}, {"title": "Introduction to Entropy.txt", "text": "They, in fact, would want to form this structure here."}, {"title": "Introduction to Entropy.txt", "text": "Okay?"}, {"title": "Introduction to Entropy.txt", "text": "So this more structured system will want to turn into this less structured system."}, {"title": "Introduction to Entropy.txt", "text": "Okay, so let's go back to our definition, or definitions of entropy."}, {"title": "Introduction to Entropy.txt", "text": "One definition states that entropy is the measure of this order of a system."}, {"title": "Introduction to Entropy.txt", "text": "So since this is more structured, there's more order, so it's less disordered."}, {"title": "Introduction to Entropy.txt", "text": "Okay?"}, {"title": "Introduction to Entropy.txt", "text": "This means there is a lower entropy or low entropy because it's more structured, more ordered."}, {"title": "Introduction to Entropy.txt", "text": "Okay?"}, {"title": "Introduction to Entropy.txt", "text": "Now, here it's the opposite."}, {"title": "Introduction to Entropy.txt", "text": "Since here there's less structure and less order, it's more disordered, so there is a higher entropy."}, {"title": "Introduction to Entropy.txt", "text": "Now let's go to our second definition of entropy, which basically states that entropy is the tendency of a system to take its most probable form."}, {"title": "Introduction to Entropy.txt", "text": "So, once again, which one is more probable?"}, {"title": "Introduction to Entropy.txt", "text": "Well, this one is more probable."}, {"title": "Introduction to Entropy.txt", "text": "Therefore, there's a higher entropy, and this guy is less probable, so there's a lower entropy."}, {"title": "Introduction to Entropy.txt", "text": "Okay, so we can refine the second law of thermodynamics into the following."}, {"title": "Introduction to Entropy.txt", "text": "The second law of thermodynamics states that the entropy of an isolated system will never decrease."}, {"title": "Introduction to Entropy.txt", "text": "It will either stay the same, or it will increase."}, {"title": "Introduction to Entropy.txt", "text": "In other words, it will never go from this to this."}, {"title": "Hund\u2019s Rule .txt", "text": "So in this lecture, I'd like to talk about Hans Rule, which is used whenever we talk about electron configuration of atoms."}, {"title": "Hund\u2019s Rule .txt", "text": "Now, before we get into Huns rule, let's recall the following fact opposite charges attract and light charges repel."}, {"title": "Hund\u2019s Rule .txt", "text": "And they do so according to Coulomb's law, which is given by the following formula the force that at either charge field due to the other charges given by constant k times charge of one times charge of two divided by distance between them squared."}, {"title": "Hund\u2019s Rule .txt", "text": "So if I take two electrons, q one and q two a distance R apart this electron, this charge q two, will feel a force due to this charge q one, the same charge, and this force will be in this direction."}, {"title": "Hund\u2019s Rule .txt", "text": "And this force is given by this law."}, {"title": "Hund\u2019s Rule .txt", "text": "Likewise, this charge Q one will also feel a force due to this charge q two."}, {"title": "Hund\u2019s Rule .txt", "text": "And the force will be in the opposite direction with the same magnitude."}, {"title": "Hund\u2019s Rule .txt", "text": "And it's also given by this equation, Coulomb's law."}, {"title": "Hund\u2019s Rule .txt", "text": "So what Coulomb's Law says is the following if we place two electrons next to each other, they will repel."}, {"title": "Hund\u2019s Rule .txt", "text": "They will create repulsion forces."}, {"title": "Hund\u2019s Rule .txt", "text": "So this leads into the following fact placing electrons into the same orbital in a subshell will create repulsion forces."}, {"title": "Hund\u2019s Rule .txt", "text": "And this explains two ideas."}, {"title": "Hund\u2019s Rule .txt", "text": "This is why a maximum of two electrons can go into an orbital."}, {"title": "Hund\u2019s Rule .txt", "text": "Because if we place three, four or five electrons into the same orbital, this will increase our force dramatically, creating a lot of repulsion forces, creating a lot of repulsion."}, {"title": "Hund\u2019s Rule .txt", "text": "And that means this idea explains the Poly Exclusion Principle, which states that a maximum two electrons can be placed into any given orbital."}, {"title": "Hund\u2019s Rule .txt", "text": "Now, this principle also explains Honduras."}, {"title": "Hund\u2019s Rule .txt", "text": "And what Hungry states is the following."}, {"title": "Hund\u2019s Rule .txt", "text": "It says that electrons will not go into an occupied orbital occupied by some electron until all the orbitals within that subshell are already filled."}, {"title": "Hund\u2019s Rule .txt", "text": "So, for example, let's look at the electron configuration of nitrogen."}, {"title": "Hund\u2019s Rule .txt", "text": "And it's the following two electrons are placed into the one s orbital."}, {"title": "Hund\u2019s Rule .txt", "text": "Two electrons are placed into the two s orbital, right?"}, {"title": "Hund\u2019s Rule .txt", "text": "We're not placing three electrons into our s orbital or four electrons, because only a maximum of two electrons can go into any given orbital because of this principle that we mentioned above."}, {"title": "Hund\u2019s Rule .txt", "text": "Now, let's look at our p orbitals."}, {"title": "Hund\u2019s Rule .txt", "text": "Remember, there are three p orbitals."}, {"title": "Hund\u2019s Rule .txt", "text": "And what Hungry tells us is that before we add two electrons into an orbital, first all the orbitals must be filled with at least one electron."}, {"title": "Hund\u2019s Rule .txt", "text": "And that's exactly why we first add one electron to the PX orbital."}, {"title": "Hund\u2019s Rule .txt", "text": "Then we add the second electron to the PY orbital."}, {"title": "Hund\u2019s Rule .txt", "text": "And then we're adding the third electron into the PV orbital to give us a total of two plus two, four plus three seven electrons."}, {"title": "Hund\u2019s Rule .txt", "text": "This nitrogen has seven protons and seven electrons in its neutral state."}, {"title": "Hund\u2019s Rule .txt", "text": "Now let's look at oxygen."}, {"title": "Hund\u2019s Rule .txt", "text": "Oxygen has eight protons, so it has eight electrons."}, {"title": "Hund\u2019s Rule .txt", "text": "So let's draw the electron configuration according to Hungry."}, {"title": "Hund\u2019s Rule .txt", "text": "So two electrons are placed into s, and two electrons are placed into the two s. Right."}, {"title": "Hund\u2019s Rule .txt", "text": "So that's because of the poly exclusion principle."}, {"title": "Hund\u2019s Rule .txt", "text": "Once again it states a maximum."}, {"title": "Hund\u2019s Rule .txt", "text": "Two electrons will go into an orbital."}, {"title": "Hund\u2019s Rule .txt", "text": "Next, we begin filling our p orbitals."}, {"title": "Hund\u2019s Rule .txt", "text": "We have three p orbitals, and now we have four electrons."}, {"title": "Hund\u2019s Rule .txt", "text": "So first, we distribute the three electrons the following way."}, {"title": "Hund\u2019s Rule .txt", "text": "We place one into P, one into Y, and then one into D. And now, since all of them are filled, my fourth electron will go into filling completely this orbital."}, {"title": "Hund\u2019s Rule .txt", "text": "This PX orbital."}, {"title": "Hund\u2019s Rule .txt", "text": "For example, if I dealt with the next atom, if I had one more electron, I place it into this y and if I had one more electron, I place it into my Z and I get a noble gas configuration."}, {"title": "Hund\u2019s Rule .txt", "text": "So Hans Rule can be represented in the following graphic way."}, {"title": "Hund\u2019s Rule .txt", "text": "So let's look at nitrogen."}, {"title": "Hund\u2019s Rule .txt", "text": "So here's my energy axis."}, {"title": "Hund\u2019s Rule .txt", "text": "And here's just my X axis."}, {"title": "Hund\u2019s Rule .txt", "text": "Now, this bar represents my one s orbital."}, {"title": "Hund\u2019s Rule .txt", "text": "This black bar represents my two S orbital."}, {"title": "Hund\u2019s Rule .txt", "text": "The reason this one is lower than this one is because one s orbital is at a lower state energy state than the two s orbitals."}, {"title": "Hund\u2019s Rule .txt", "text": "And so the two s is a bit higher."}, {"title": "Hund\u2019s Rule .txt", "text": "Likewise, the two PX and the two PX."}, {"title": "Hund\u2019s Rule .txt", "text": "Two PY and two PZ are higher than either this guy and this guy."}, {"title": "Hund\u2019s Rule .txt", "text": "That means they will be higher."}, {"title": "Hund\u2019s Rule .txt", "text": "And these guys aren't the same level."}, {"title": "Hund\u2019s Rule .txt", "text": "So that means they will be at the same level."}, {"title": "Hund\u2019s Rule .txt", "text": "So now, when I place electrons, I place them in the following way."}, {"title": "Hund\u2019s Rule .txt", "text": "The upward arrow represents the electron spin of plus one half."}, {"title": "Hund\u2019s Rule .txt", "text": "The downward arrow represents the electron spin of negative one half."}, {"title": "Hund\u2019s Rule .txt", "text": "So first I draw my up arrow, my down arrow, and I finished with the one s.\nNext, I put two electrons into my two s. Upward arrow, downward arrow."}, {"title": "Hund\u2019s Rule .txt", "text": "And finally, I put one electron in each."}, {"title": "Hund\u2019s Rule .txt", "text": "So I begin with the plus one."}, {"title": "Hund\u2019s Rule .txt", "text": "Half."}, {"title": "Hund\u2019s Rule .txt", "text": "So upward, upward and upward."}, {"title": "Hund\u2019s Rule .txt", "text": "And now I'm done."}, {"title": "Hund\u2019s Rule .txt", "text": "This is my graphic representation of Hans rule for nitrogen."}, {"title": "Hund\u2019s Rule .txt", "text": "Now let's look at the graphic representation for Hans Rule for oxygen."}, {"title": "Hund\u2019s Rule .txt", "text": "So we start by drawing the same bars."}, {"title": "Hund\u2019s Rule .txt", "text": "And now we start filling our orbitals."}, {"title": "Hund\u2019s Rule .txt", "text": "So up down."}, {"title": "Hund\u2019s Rule .txt", "text": "Up down, up up."}, {"title": "Hund\u2019s Rule .txt", "text": "And then I take my Fourth Electron and Final Electron and put it into my two X."}, {"title": "Hund\u2019s Rule .txt", "text": "So I draw it down one."}, {"title": "Hund\u2019s Rule .txt", "text": "Because according to our rules, we can't have electrons that have the same spin in the same orbital."}, {"title": "Hund\u2019s Rule .txt", "text": "If we put two electrons in the same orbital, they must always have opposite spin."}, {"title": "Hund\u2019s Rule .txt", "text": "So up and down."}, {"title": "Hund\u2019s Rule .txt", "text": "And this is hungry."}, {"title": "Acidity of Hydrides .txt", "text": "In this lecture we're going to talk about acidity of Hydrides."}, {"title": "Acidity of Hydrides .txt", "text": "Now, any compound that's composed of two elements in which one element is a hydrogen is called a Hydride."}, {"title": "Acidity of Hydrides .txt", "text": "Now, Hydrides have varying levels of acidity."}, {"title": "Acidity of Hydrides .txt", "text": "They could be acidic, neutral, or basic."}, {"title": "Acidity of Hydrides .txt", "text": "Now, if we look at our emeritus table, we see a trend."}, {"title": "Acidity of Hydrides .txt", "text": "We see that as we go across the period from left to right, the acidity of Hydrides increases."}, {"title": "Acidity of Hydrides .txt", "text": "And as we go down a group, the acidity of Hydride also increases."}, {"title": "Acidity of Hydrides .txt", "text": "So that means atoms that exist on the left side of the period that form Hydrides are basic atoms that exist in the middle, that transition atoms or transition metals that form Hydrides with H form either mutual or basic Hydrides."}, {"title": "Acidity of Hydrides .txt", "text": "And for the most part, atoms that I found on this part on the right side form either weak acids, strong acids, or neutral Hydrides."}, {"title": "Acidity of Hydrides .txt", "text": "So for example, let's look at sodium and lithium and potassium."}, {"title": "Acidity of Hydrides .txt", "text": "All these guys are found on the left side."}, {"title": "Acidity of Hydrides .txt", "text": "That means they will form basic Hydrides."}, {"title": "Acidity of Hydrides .txt", "text": "And in fact, all metal Hydrides are either basic or neutral Hydrides."}, {"title": "Acidity of Hydrides .txt", "text": "Now, we could also say, with the exception of one molecule, all nonmetal Hydrides are either neutral or acidic."}, {"title": "Acidity of Hydrides .txt", "text": "The exception is ammonia."}, {"title": "Acidity of Hydrides .txt", "text": "Ammonia is the only nonmetal that forms a weak base."}, {"title": "Acidity of Hydrides .txt", "text": "Now, let's examine the right side of the periodic table."}, {"title": "Acidity of Hydrides .txt", "text": "On the right side, all the way on the right side, and all the way down, we see that we have strong acids."}, {"title": "Acidity of Hydrides .txt", "text": "So HCL and HBR are both strong acids."}, {"title": "Acidity of Hydrides .txt", "text": "Now, because fluorine is found on the top, it's a weak acid."}, {"title": "Acidity of Hydrides .txt", "text": "Remember, as we go up a group, the acid strength decreases."}, {"title": "Acidity of Hydrides .txt", "text": "So this guy is a weak acid."}, {"title": "Acidity of Hydrides .txt", "text": "Water is neutral, so we leave that alone."}, {"title": "Acidity of Hydrides .txt", "text": "Now, these two guys are weak acids as well, because remember, we move back a group, that means our acid strength decreased."}, {"title": "Acidity of Hydrides .txt", "text": "So these guys are weak acids."}, {"title": "Acidity of Hydrides .txt", "text": "Now, if we move one more group, we get weak basis."}, {"title": "Acidity of Hydrides .txt", "text": "And if we get if we move one more group, we get neutral."}, {"title": "Introduction to Molecular Orbitals .txt", "text": "Now, in these next few lectures, we're going to begin our discussion on molecular orbitals."}, {"title": "Introduction to Molecular Orbitals .txt", "text": "Now, previously, we spoke about atomic orbitals and covalent bonds."}, {"title": "Introduction to Molecular Orbitals .txt", "text": "In this lecture, we'll see how atomic orbitals of atoms combine to form covalent bonds, which are really molecular orbitals."}, {"title": "Introduction to Molecular Orbitals .txt", "text": "So let's begin with the following simple example."}, {"title": "Introduction to Molecular Orbitals .txt", "text": "So let's say we want to combine two neutral H atoms in a way to form a diatomic H two molecule."}, {"title": "Introduction to Molecular Orbitals .txt", "text": "So we want to form a covalent bond."}, {"title": "Introduction to Molecular Orbitals .txt", "text": "So what must happen first?"}, {"title": "Introduction to Molecular Orbitals .txt", "text": "Well, initially, these two mutual H atoms are very far apart."}, {"title": "Introduction to Molecular Orbitals .txt", "text": "And since they're neutral, they each have a proton, a nucleus, and an electron surrounding that nucleus."}, {"title": "Introduction to Molecular Orbitals .txt", "text": "So what happens as I begin to bring these molecules closer and closer and closer?"}, {"title": "Introduction to Molecular Orbitals .txt", "text": "Well, as I begin moving them closer, they begin to feel electrostatic force Coulomb's law."}, {"title": "Introduction to Molecular Orbitals .txt", "text": "Now, as I move them closer and closer, eventually I will bring them to a point when the electrostatic repulsion of the nuclei of the protons down the nuclei will balance out the electrostatic attraction between the electrons and the protons in the nuclei."}, {"title": "Introduction to Molecular Orbitals .txt", "text": "In other words, let's look at the following example."}, {"title": "Introduction to Molecular Orbitals .txt", "text": "So, when I have these two protons a certain distance apart, the repulsion between these two protons going this way will equal the attraction of these electrons."}, {"title": "Introduction to Molecular Orbitals .txt", "text": "In other words, this proton of H atom one will attract the electron of H atom two."}, {"title": "Introduction to Molecular Orbitals .txt", "text": "And likewise, H atom two will attract the electron of H atom one."}, {"title": "Introduction to Molecular Orbitals .txt", "text": "And in fact, when there are 0.7\nangstromes, angstrom simply means one times ten to the negative 10 meters apart."}, {"title": "Introduction to Molecular Orbitals .txt", "text": "When they're this distance apart, a bond will form, a covalent bond will form."}, {"title": "Introduction to Molecular Orbitals .txt", "text": "And in fact, as you move the two H atoms closer and closer from a far distance apart, energy begins to decrease until we reach this point, until we reach 0.7\nangstromes away."}, {"title": "Introduction to Molecular Orbitals .txt", "text": "So if we graph energy versus our distance between them, we will see that a distance far apart, somewhere right here, we're going to have some energy."}, {"title": "Introduction to Molecular Orbitals .txt", "text": "And as we begin moving them closer and closer, our energy will begin to decrease until we reach this point."}, {"title": "Introduction to Molecular Orbitals .txt", "text": "And at this point, we have the minimum amount of energy."}, {"title": "Introduction to Molecular Orbitals .txt", "text": "In other words, nature likes to minimize energy."}, {"title": "Introduction to Molecular Orbitals .txt", "text": "The more destabilizing it is, the more energy we have."}, {"title": "Introduction to Molecular Orbitals .txt", "text": "The less energy we have, the more stabilizing our compound is."}, {"title": "Introduction to Molecular Orbitals .txt", "text": "So, in other words, the beginning condition, our initial atoms are at a higher energy than our final molecule."}, {"title": "Introduction to Molecular Orbitals .txt", "text": "Now, what happens when I continue pushing them closer and closer?"}, {"title": "Introduction to Molecular Orbitals .txt", "text": "Well, as that begins pushing them closer and closer and closer, the repulsion forces begin to increase dramatically."}, {"title": "Introduction to Molecular Orbitals .txt", "text": "And that's exactly why we see that as we go past 0.7 atroms, our energy begins to increase."}, {"title": "Introduction to Molecular Orbitals .txt", "text": "So as you bring atoms closer and closer, repulsion of the positively charged nuclei causes a sharp increase in energy, as we see here."}, {"title": "Introduction to Molecular Orbitals .txt", "text": "So as they're moving closer past the distance, the electrons, as well, as protons begin to repel one another, and the energy dramatically increases once again."}, {"title": "Introduction to Molecular Orbitals .txt", "text": "To recap, nature likes to form stabilizing structures."}, {"title": "Introduction to Molecular Orbitals .txt", "text": "Nature will not form a structure that is higher in energy."}, {"title": "Introduction to Molecular Orbitals .txt", "text": "In other words, if this was higher in energy than this, this molecule would not form."}, {"title": "Introduction to Molecular Orbitals .txt", "text": "The reason this form spontaneously is because our energy of initial molecules or atoms is lower than the final."}, {"title": "Introduction to Molecular Orbitals .txt", "text": "So now, let's examine atomic orbitals."}, {"title": "Introduction to Molecular Orbitals .txt", "text": "So, what is the atomic orbital that our electron is in?"}, {"title": "Introduction to Molecular Orbitals .txt", "text": "Well, it's the one S orbital."}, {"title": "Introduction to Molecular Orbitals .txt", "text": "So let's say we have this atom."}, {"title": "Introduction to Molecular Orbitals .txt", "text": "Let's call it ha subscript A."}, {"title": "Introduction to Molecular Orbitals .txt", "text": "And let's call this guy H subscript B."}, {"title": "Introduction to Molecular Orbitals .txt", "text": "So this here, this PSI, Greek letter PSI, simply represents the orbital or wave function."}, {"title": "Introduction to Molecular Orbitals .txt", "text": "So let's say PSI subscript haply means that this is the one S orbital of our ha atom."}, {"title": "Introduction to Molecular Orbitals .txt", "text": "And this is the one s orbital of our HB atom."}, {"title": "Introduction to Molecular Orbitals .txt", "text": "So when these orbitals atomic orbitals are very far apart, nothing really happens."}, {"title": "Introduction to Molecular Orbitals .txt", "text": "But as I move them closer and closer, eventually, when I get to this point, these atomic orbitals will overlap, and they will create something known as the molecular orbital or molecular bonding orbital."}, {"title": "Introduction to Molecular Orbitals .txt", "text": "Now, this guy is represented by PSI phi."}, {"title": "Introduction to Molecular Orbitals .txt", "text": "So phi bonding is our molecular orbital."}, {"title": "Introduction to Molecular Orbitals .txt", "text": "So when we see this symbol, we usually think atomic orbitals."}, {"title": "Introduction to Molecular Orbitals .txt", "text": "And this is five."}, {"title": "Introduction to Molecular Orbitals .txt", "text": "When we see this symbol five, we think about molecular orbitals."}, {"title": "Introduction to Molecular Orbitals .txt", "text": "So, once again, atomic orbitals will combine two form molecular orbitals, or also known as covalent bonds."}, {"title": "Introduction to Molecular Orbitals .txt", "text": "Now, from quantum mechanics, we know that whatever number of atomic orbitals that combine, they will form the same amount of molecular orbitals."}, {"title": "Introduction to Molecular Orbitals .txt", "text": "In other words, there's a conservation number that we have to take into consideration."}, {"title": "Introduction to Molecular Orbitals .txt", "text": "So, because two atomic orbitals combined, we should form two molecular orbitals."}, {"title": "Introduction to Molecular Orbitals .txt", "text": "But here, we see only one."}, {"title": "Introduction to Molecular Orbitals .txt", "text": "So, in the next lecture, we're going to see what the second molecular orbital is."}, {"title": "Acid Strength.txt", "text": "In this lecture we're going to look at the different things that make up a good asset."}, {"title": "Acid Strength.txt", "text": "So before we talk about acid and basis, we must define what acid and bases are."}, {"title": "Acid Strength.txt", "text": "Well, if you want to learn more about the various types of definitions that exist between acid and bases, check out the link below."}, {"title": "Acid Strength.txt", "text": "In this lecture we're going to focus on the bronzed lottery acid based concept."}, {"title": "Acid Strength.txt", "text": "So according to that definition, acids are defined by their ability to donate an H plus ion, while bases are defined by their ability to accept an H plus ion."}, {"title": "Acid Strength.txt", "text": "So what makes a compound X a better acid than compound Y?"}, {"title": "Acid Strength.txt", "text": "Well, stronger acids are better at donating than H plus ion than weaker acids are."}, {"title": "Acid Strength.txt", "text": "And stronger bases are better at accepting that H plus ion than weaker bases."}, {"title": "Acid Strength.txt", "text": "That means the reason that compound X is a better asset than compound Y well, is because compound X releases that H ion with greater ease compared to compound Y."}, {"title": "Acid Strength.txt", "text": "Now, three things make up a good asset bond strength, polarity of bond, and stability of conjugate base."}, {"title": "Acid Strength.txt", "text": "So how strong is the bond connecting the H ion and the atom in the compound?"}, {"title": "Acid Strength.txt", "text": "Well, suppose you're holding somebody's hand and you're holding their hand tightly with a good grip."}, {"title": "Acid Strength.txt", "text": "Well, then the other person will not be able to let go of their hand that easily."}, {"title": "Acid Strength.txt", "text": "However, if your grip is weak and you're not holding it tightly, then that person will be able to let go of their hand the same way that weak bonds will release the H plus ion with greater ease."}, {"title": "Acid Strength.txt", "text": "So whenever you have a base that comes around, that base will be able to take away that H plus ion if the bond is weak."}, {"title": "Acid Strength.txt", "text": "So weaker bonds equals better acids."}, {"title": "Acid Strength.txt", "text": "So let's look at the polarity of our bond."}, {"title": "Acid Strength.txt", "text": "So how polar is our bond?"}, {"title": "Acid Strength.txt", "text": "Let's examine HCH bond in a methane and an HCL bond in a hydrochloric acid or HCL."}, {"title": "Acid Strength.txt", "text": "So the strength of these bonds is relatively the same."}, {"title": "Acid Strength.txt", "text": "So if we strictly look at part C, the bond strength, we will determine that our acid strength is the same."}, {"title": "Acid Strength.txt", "text": "But that's not the case."}, {"title": "Acid Strength.txt", "text": "This is a much better asset than our methane molecule."}, {"title": "Acid Strength.txt", "text": "So why is that?"}, {"title": "Acid Strength.txt", "text": "Well, we have to look at the polarity."}, {"title": "Acid Strength.txt", "text": "Remember, polarity comes from electronegativity."}, {"title": "Acid Strength.txt", "text": "And the greater the difference in electronegativity, the more polar our bond is."}, {"title": "Acid Strength.txt", "text": "So let's look at this guy."}, {"title": "Acid Strength.txt", "text": "The difference between electronegativity between the C atom and the H atom is smaller than the difference between a CL atom and the H atom."}, {"title": "Acid Strength.txt", "text": "And that's because the CL atom is much more electronic negative."}, {"title": "Acid Strength.txt", "text": "That means it's going to pull the electrons toward itself."}, {"title": "Acid Strength.txt", "text": "So the density will not be equal, whereas here it will be equal, or pretty much equal."}, {"title": "Acid Strength.txt", "text": "Therefore, this section of the bond will be weak."}, {"title": "Acid Strength.txt", "text": "And so when a base comes around, it will be able to pull away this H atom with greater ease."}, {"title": "Acid Strength.txt", "text": "Therefore, the more polar our bond, the more likely that it will break and release that H plus ion."}, {"title": "Acid Strength.txt", "text": "Finally, let's look at the stability of conjugate bases."}, {"title": "Acid Strength.txt", "text": "Now, if you forgot what a conjugate acid in base is, check out the link below."}, {"title": "Acid Strength.txt", "text": "Now, we're going to explore the difference between chloric acid and hypochlorous acid."}, {"title": "Acid Strength.txt", "text": "So if we look at the polarity and the bond strength, we see that this ho bond and this ho bond are identical."}, {"title": "Acid Strength.txt", "text": "And that means, according to polarity and bond strength, these assets should have the same strain."}, {"title": "Acid Strength.txt", "text": "But experimentally, we know that chlorot acid is a better asset than the Hypochlorous acid."}, {"title": "Acid Strength.txt", "text": "So let's examine why this has to do with conjugate basis."}, {"title": "Acid Strength.txt", "text": "Let's look at the conjugate base of Hypochlorous acid."}, {"title": "Acid Strength.txt", "text": "While when this H associates, it creates a negative charge on the O atom, creating this guy here."}, {"title": "Acid Strength.txt", "text": "Now, this guy can be resonant stabilized by the formation of a double bond, and this creates a negative charge on the seal atom."}, {"title": "Acid Strength.txt", "text": "So we have two resonance stabilized states."}, {"title": "Acid Strength.txt", "text": "Now, let's examine the conjugate base of our chloric acid."}, {"title": "Acid Strength.txt", "text": "Well, this guy is resonant stabilized by three states, in fact, four states."}, {"title": "Acid Strength.txt", "text": "I'll show you the last one in a bit."}, {"title": "Acid Strength.txt", "text": "So this negative atom can be distributed to this oxygen and then this oxygen."}, {"title": "Acid Strength.txt", "text": "And that happens when this guy forms a double bond, displacing this bond, forming a negative bond here."}, {"title": "Acid Strength.txt", "text": "And then this lone pair forms a double bond with this bond, displacing this lone pair, creating a negative charge here."}, {"title": "Acid Strength.txt", "text": "In fact, a fourth resonance stabilized state exists in which three double bonds exist, and the CL atom has a negative charge."}, {"title": "Acid Strength.txt", "text": "So we see that resonance stabilization is good."}, {"title": "Acid Strength.txt", "text": "Whenever we have more resonance stabilization, that means we have a more stable conjugate base."}, {"title": "Acid Strength.txt", "text": "So this guy will exist, and it will be more likely that it will exist than this guy."}, {"title": "Acid Strength.txt", "text": "And therefore, chloride acid will be more likely to go this way to lose and dissociate and to form this state than this guy."}, {"title": "Acid Strength.txt", "text": "This guy will be less likely to dissociate because it's only stabilized by two resonance stabilized states, or its conjugate base is only stabilized by two states versus four states in this case."}, {"title": "Acid Strength.txt", "text": "So, once again, the more stable our conjugate base is, the stronger our asset."}, {"title": "Acid Strength.txt", "text": "That also means as acid strain decreases, say, from going this guy to going to this guy, the strength of our conjugate base increases."}, {"title": "Acid Strength.txt", "text": "In other words, this guy will be more likely to accept an atom and go to this guy than this guy because this guy exists by itself in a more stable state."}, {"title": "Acid Strength.txt", "text": "If you have this guy and this guy, this guy will be less likely to take an H atom and create chloric acid than this guy."}, {"title": "Cell Voltage Equation .txt", "text": "In this example, we begin with the following redox reaction on the standard conditions at a 25 degree Celsius."}, {"title": "Cell Voltage Equation .txt", "text": "Now, our goal is to find the equilibrium constant of the above redox reaction on the DTA conditions."}, {"title": "Cell Voltage Equation .txt", "text": "So let's begin by first writing out the two half reactions of this reduction reaction."}, {"title": "Cell Voltage Equation .txt", "text": "So let's see which guy is oxidized and which guy is reduced."}, {"title": "Cell Voltage Equation .txt", "text": "Well, our iron atom goes from a neutral charge to a plus two charge, while our cavmium atom goes from a plus two charge to a neutral charge."}, {"title": "Cell Voltage Equation .txt", "text": "That means this atom loses two electrons and this atom gains those same two electrons."}, {"title": "Cell Voltage Equation .txt", "text": "So this is our oxidized atom and our reduced atom or our reducing agent and oxidizing agent."}, {"title": "Cell Voltage Equation .txt", "text": "So let's go to step one and let's see our two half reactions."}, {"title": "Cell Voltage Equation .txt", "text": "So our oxidation half reaction is the following."}, {"title": "Cell Voltage Equation .txt", "text": "Our solid iron becomes a positively charged molecule plus two electrons because it releases those two electrons while our cadmium aqueous atom gains those two electrons forming our cadmium solid."}, {"title": "Cell Voltage Equation .txt", "text": "So this is our reduction reaction and oxidation reaction."}, {"title": "Cell Voltage Equation .txt", "text": "So let's look at the cell diagram for this electrochemical cell."}, {"title": "Cell Voltage Equation .txt", "text": "So remember, these two vertical lines represent the sole bridge and these guys simply represent separations of phases."}, {"title": "Cell Voltage Equation .txt", "text": "So this and this are in different phases and these guys are in different phases also."}, {"title": "Cell Voltage Equation .txt", "text": "So this is our anode and this is our cathode."}, {"title": "Cell Voltage Equation .txt", "text": "So what happens is two electrons leave this atom forming our aqueous iron atom and these two electrons travel via the conductor to this guy reacting with this positively charged atom forming our solid cadmium."}, {"title": "Cell Voltage Equation .txt", "text": "So let's go to step two."}, {"title": "Cell Voltage Equation .txt", "text": "Now, in step two and three, what we want to do or do is find a cell voltage of our electrochemical cell and then use the cell voltage to find our equilibrium constant KC."}, {"title": "Cell Voltage Equation .txt", "text": "So let's go to step two."}, {"title": "Cell Voltage Equation .txt", "text": "Now, this is our formula that we want to use to find the cell voltage where this is the cell voltage of the reduction reaction and the cell voltage of the oxidation reaction."}, {"title": "Cell Voltage Equation .txt", "text": "Now, we basically look these guys up on our table for reduction half reactions on the statement conditions and we find that our reduction cell voltage is zero point 43 negative, while our oxidation half reaction is negative zero point 44."}, {"title": "Cell Voltage Equation .txt", "text": "Well, actually our reduction going this way because only reduction half reactions are listed."}, {"title": "Cell Voltage Equation .txt", "text": "So we have to look at the guy going this way."}, {"title": "Cell Voltage Equation .txt", "text": "So that is negative zero point 44."}, {"title": "Cell Voltage Equation .txt", "text": "Now, I put this negative here in here because we want to convert this to an oxidation because in this anode oxidation that reduction occurs and that's why we have the negative sign here."}, {"title": "Cell Voltage Equation .txt", "text": "So what we get is these negatives become a positive and we basically add this guy to this guy and we get zero point 37 volts."}, {"title": "Cell Voltage Equation .txt", "text": "This is our cell voltage of our electrochemical cell."}, {"title": "Cell Voltage Equation .txt", "text": "Now, in the previous lecture we learned that there's a relationship between our cell voltage and our equilibrium constant, namely this equation here."}, {"title": "Cell Voltage Equation .txt", "text": "Now, we also saw in that same lecture that we can convert this formula at 25 degrees Celsius to the following formula."}, {"title": "Cell Voltage Equation .txt", "text": "Log k equals number of moles times our cell voltage divided by this number here."}, {"title": "Cell Voltage Equation .txt", "text": "Zero point 52."}, {"title": "Cell Voltage Equation .txt", "text": "Now, this number comes from the fact that both r and F are constants."}, {"title": "Cell Voltage Equation .txt", "text": "And at 25 degrees Celsius, t is also constant."}, {"title": "Cell Voltage Equation .txt", "text": "Now t is in Kelvin."}, {"title": "Cell Voltage Equation .txt", "text": "And we also basically converted our natural log to log of base ten."}, {"title": "Cell Voltage Equation .txt", "text": "Now, let's plug our guides in."}, {"title": "Cell Voltage Equation .txt", "text": "So our E is from here, and n, we look at this equation."}, {"title": "Cell Voltage Equation .txt", "text": "We see that N represents two moles of electrons."}, {"title": "Cell Voltage Equation .txt", "text": "So n is two."}, {"title": "Cell Voltage Equation .txt", "text": "That's what we get."}, {"title": "Cell Voltage Equation .txt", "text": "Two times zero point 37 results from this guy divided by zero point 52, and we get 1.25 equals log k.\nNow, we change this entire thing to exponents, and we get ten to the 1.5."}, {"title": "Cell Voltage Equation .txt", "text": "You plug that into the calculator, and it's approximately 17.8."}, {"title": "Cell Voltage Equation .txt", "text": "So our K is 17.8."}, {"title": "Cell Voltage Equation .txt", "text": "And what does that mean?"}, {"title": "Cell Voltage Equation .txt", "text": "Well, remember we said if our K is above one, that means our reaction is product favorite."}, {"title": "Cell Voltage Equation .txt", "text": "It's spontaneous."}, {"title": "Cell Voltage Equation .txt", "text": "So this guy, the equilibrium lies on the right."}, {"title": "Cell Voltage Equation .txt", "text": "That means almost all of these guys are converted to our products."}, {"title": "Cell Voltage Equation .txt", "text": "And this is the same thing as our e. Remember, our E says what our E gives us a positive value for cell voltage and what the a positive value for cell voltage mean?"}, {"title": "Cell Voltage Equation .txt", "text": "Remember, a positive value for cell voltage means our reaction is product favored, and a negative value means it's reacting favored."}, {"title": "Cell Voltage Equation .txt", "text": "So this and this guy agree, and they state that this reaction will be favored in this direction."}, {"title": "Polar and Nonpolar Covalent Bonds .txt", "text": "In this lecture, I'd like to briefly talk about two types of important bonds that are found in organic chemistry."}, {"title": "Polar and Nonpolar Covalent Bonds .txt", "text": "So let's begin."}, {"title": "Polar and Nonpolar Covalent Bonds .txt", "text": "So here we have the nonpolar covalent bonds, and here we have the polar covalent bond."}, {"title": "Polar and Nonpolar Covalent Bonds .txt", "text": "Now, notice right off the bat the similarity."}, {"title": "Polar and Nonpolar Covalent Bonds .txt", "text": "Both guys, both bonds are covalent bonds."}, {"title": "Polar and Nonpolar Covalent Bonds .txt", "text": "And what, what that simply means is that there is a sharing of electrons."}, {"title": "Polar and Nonpolar Covalent Bonds .txt", "text": "In other words, one atom donates an electron and a second atom also donates an electron."}, {"title": "Polar and Nonpolar Covalent Bonds .txt", "text": "The difference lies is a polarity and we'll see what that means in just a second."}, {"title": "Polar and Nonpolar Covalent Bonds .txt", "text": "So let's begin with the non polar covalent bond."}, {"title": "Polar and Nonpolar Covalent Bonds .txt", "text": "So let's suppose we have two atoms."}, {"title": "Polar and Nonpolar Covalent Bonds .txt", "text": "So two atoms that are exactly the same mean they have the same amount of protons in the nucleus and the same amount of electrons."}, {"title": "Polar and Nonpolar Covalent Bonds .txt", "text": "So here we have our picture where we have our nucleus one with some amount of electrons and nucleus two with the same amount with the same number of electrons."}, {"title": "Polar and Nonpolar Covalent Bonds .txt", "text": "And each nucleus or each atom donates an electron."}, {"title": "Polar and Nonpolar Covalent Bonds .txt", "text": "So one coming from this atom and the second coming from this atom."}, {"title": "Polar and Nonpolar Covalent Bonds .txt", "text": "So let's look at Coulomb's law for a second."}, {"title": "Polar and Nonpolar Covalent Bonds .txt", "text": "Coulomb's law gives us the force felt by two charges some distance apart."}, {"title": "Polar and Nonpolar Covalent Bonds .txt", "text": "What it states is the following."}, {"title": "Polar and Nonpolar Covalent Bonds .txt", "text": "If we have two charges, q one and Q two, if we multiply them together and multiplied by the constant k and divided by the distance between their center of charges squared, we get the force that each charge feels due to the other charge."}, {"title": "Polar and Nonpolar Covalent Bonds .txt", "text": "Remember, plus charges repel and plus and minus attract."}, {"title": "Polar and Nonpolar Covalent Bonds .txt", "text": "So notice what we have here."}, {"title": "Polar and Nonpolar Covalent Bonds .txt", "text": "The charge in this nucleus is the same as the charge in this nucleus because we have the same amount of protons in those nuclei."}, {"title": "Polar and Nonpolar Covalent Bonds .txt", "text": "And we both have one electrons, one electron here and one electron here."}, {"title": "Polar and Nonpolar Covalent Bonds .txt", "text": "And they also have the same amount of charge."}, {"title": "Polar and Nonpolar Covalent Bonds .txt", "text": "So that means that this nuclei will exert a force on this electron and this force will be equal to the force that this nuclei nucleus exerts on this electron."}, {"title": "Polar and Nonpolar Covalent Bonds .txt", "text": "So this electron will pull this or this proton will pull this electron with the same amount of force that this proton will pull on this electron."}, {"title": "Polar and Nonpolar Covalent Bonds .txt", "text": "So there will be an equal distribution of charge."}, {"title": "Polar and Nonpolar Covalent Bonds .txt", "text": "These electrons will be found equidistant between these two nuclei."}, {"title": "Polar and Nonpolar Covalent Bonds .txt", "text": "Distance will be the same exact."}, {"title": "Polar and Nonpolar Covalent Bonds .txt", "text": "And this only occurs when we have the same amount of protons found in the nucleus."}, {"title": "Polar and Nonpolar Covalent Bonds .txt", "text": "So for example, if we have an H and an H, both nuclei have one protons each."}, {"title": "Polar and Nonpolar Covalent Bonds .txt", "text": "If we have an F and an F, both nuclei have nine protons each and so on."}, {"title": "Polar and Nonpolar Covalent Bonds .txt", "text": "Basically, when we have two of the same atoms, we're going to have a non polar covalent bond as we have here and as we have here."}, {"title": "Polar and Nonpolar Covalent Bonds .txt", "text": "Now, notice we have a double bond here."}, {"title": "Polar and Nonpolar Covalent Bonds .txt", "text": "But it doesn't change the fact that this is a nonpolar covalent bond because we have an oxygen with some amount of protons and a second oxygen with the same amount of protons."}, {"title": "Polar and Nonpolar Covalent Bonds .txt", "text": "Now, another way to look at it is via electronegativity."}, {"title": "Polar and Nonpolar Covalent Bonds .txt", "text": "Now, both atoms have the same amount of electronegativity and that simply means they will attract electrons with the same affinity."}, {"title": "Polar and Nonpolar Covalent Bonds .txt", "text": "And that basically means that our electrons will be found smack in the middle."}, {"title": "Polar and Nonpolar Covalent Bonds .txt", "text": "They'll be equidistant between our two atoms."}, {"title": "Polar and Nonpolar Covalent Bonds .txt", "text": "And so we're going to have symmetry."}, {"title": "Polar and Nonpolar Covalent Bonds .txt", "text": "In other words, if we take a line and cross it this way, this section will be symmetrical to this section."}, {"title": "Polar and Nonpolar Covalent Bonds .txt", "text": "And that means we're going to have a non polar covalent bond."}, {"title": "Polar and Nonpolar Covalent Bonds .txt", "text": "Now let's look at polar covalent bonds."}, {"title": "Polar and Nonpolar Covalent Bonds .txt", "text": "Polar covalent bond simply means there will be an unequal distribution of charge."}, {"title": "Polar and Nonpolar Covalent Bonds .txt", "text": "And let's see why."}, {"title": "Polar and Nonpolar Covalent Bonds .txt", "text": "Well, suppose we have an atom and a second atom that have different number of protons in their nuclei."}, {"title": "Polar and Nonpolar Covalent Bonds .txt", "text": "Suppose we have a larger atom with a larger number of protons than this atom."}, {"title": "Polar and Nonpolar Covalent Bonds .txt", "text": "And what that basically means, because of coulomb law, because the charge will be greater for this nucleus than for this nucleus, the force that these electrons feel due to this nucleus will be larger than due to this nucleus."}, {"title": "Polar and Nonpolar Covalent Bonds .txt", "text": "And so there will be an unequal sharing or an unequal distribution of electrons."}, {"title": "Polar and Nonpolar Covalent Bonds .txt", "text": "So there will be an unequal distribution of charge between these two atoms."}, {"title": "Polar and Nonpolar Covalent Bonds .txt", "text": "And that means we're going to have a polar covalent bond."}, {"title": "Polar and Nonpolar Covalent Bonds .txt", "text": "Now, another way we're presenting this is by the following depiction."}, {"title": "Polar and Nonpolar Covalent Bonds .txt", "text": "So because our electrons will be closer to the larger atom, we're going to develop a partial, not a full, but a partial negative charge."}, {"title": "Polar and Nonpolar Covalent Bonds .txt", "text": "This simply means partial negative."}, {"title": "Polar and Nonpolar Covalent Bonds .txt", "text": "Now, there will be a partial positive charge because electrons will be shifted this way."}, {"title": "Polar and Nonpolar Covalent Bonds .txt", "text": "There will be a partial positive charge on this smaller atom."}, {"title": "Polar and Nonpolar Covalent Bonds .txt", "text": "Now, examples include HF, hohc and many, many more examples."}, {"title": "Polar and Nonpolar Covalent Bonds .txt", "text": "Basically, whenever you have two different atoms, such as here HF, we're going to have an equal distribution of charge."}, {"title": "Polar and Nonpolar Covalent Bonds .txt", "text": "Electrons are going to be closer to the larger atom because this f, for example, has nine protons, while this h has only one proton."}, {"title": "Polar and Nonpolar Covalent Bonds .txt", "text": "So our nucleus will pull these electrons stronger than the h. So our electrons will be closer this way."}, {"title": "Polar and Nonpolar Covalent Bonds .txt", "text": "Now, another way of representing this unequal distribution is by using this arrow."}, {"title": "Polar and Nonpolar Covalent Bonds .txt", "text": "So we draw an arrow towards where our electrons are being pulled and our electrons are being pulled towards the larger nucleus."}, {"title": "Polar and Nonpolar Covalent Bonds .txt", "text": "So towards the f.\nAnd we draw kind of a plus sign on the end where there's a partial positive charge."}, {"title": "Polar and Nonpolar Covalent Bonds .txt", "text": "So the same thing goes for h and o, we're going to have an arrow this way and we're going to have an arrow this way."}, {"title": "Polar and Nonpolar Covalent Bonds .txt", "text": "Now, another way of looking at this is via electronegativity."}, {"title": "Polar and Nonpolar Covalent Bonds .txt", "text": "The atom that has a larger electronegativity, it will pull or attract electrons more strongly."}, {"title": "Polar and Nonpolar Covalent Bonds .txt", "text": "That means we're going to have because this one is more electronegative than this atom."}, {"title": "Polar and Nonpolar Covalent Bonds .txt", "text": "And this one is more electronegative than this and this is more electronegative than this."}, {"title": "Polar and Nonpolar Covalent Bonds .txt", "text": "We're going to have our error pointing in this direction and we're going to have a polar covalent bond."}, {"title": "Polar and Nonpolar Covalent Bonds .txt", "text": "So once again, to recap, non polar covalent and polar covalent are both covalent bonds, meaning there is a sharing of electrons in one."}, {"title": "Polar and Nonpolar Covalent Bonds .txt", "text": "However, there is an equal sharing."}, {"title": "Polar and Nonpolar Covalent Bonds .txt", "text": "In the second one, there is an unequal sharing."}, {"title": "Cis-Trans Z-e Isomer Stability .txt", "text": "So for any given alkene, may different types of isomers can exist."}, {"title": "Cis-Trans Z-e Isomer Stability .txt", "text": "In this lecture we're going to compare the sits or the Z isomers with the trans or the E isomers."}, {"title": "Cis-Trans Z-e Isomer Stability .txt", "text": "And we're going to discuss which ones are more stable."}, {"title": "Cis-Trans Z-e Isomer Stability .txt", "text": "So let's suppose we're working with three hexane."}, {"title": "Cis-Trans Z-e Isomer Stability .txt", "text": "Now three hexane has two types of isomers."}, {"title": "Cis-Trans Z-e Isomer Stability .txt", "text": "It has the trans three hexen isomer or the e three hexenisomer."}, {"title": "Cis-Trans Z-e Isomer Stability .txt", "text": "And there's also the S three hexenisomer or the Z three hexane isomer."}, {"title": "Cis-Trans Z-e Isomer Stability .txt", "text": "Now, trans simply means the smaller H groups are on opposite sides of the double bond, while the E means that the two higher priority groups are in opposite sides of our double bond."}, {"title": "Cis-Trans Z-e Isomer Stability .txt", "text": "Likewise, sin simply means that the two H groups are on the same side of the double bond, while the Z means that the two priority, the higher priority groups are the same side of the double bond."}, {"title": "Cis-Trans Z-e Isomer Stability .txt", "text": "So we have trans and we have the CIS three hexane."}, {"title": "Cis-Trans Z-e Isomer Stability .txt", "text": "So let's examine our three dimensional model of this three hexane."}, {"title": "Cis-Trans Z-e Isomer Stability .txt", "text": "So here we have our CIS three hexane."}, {"title": "Cis-Trans Z-e Isomer Stability .txt", "text": "So here's our double bond and here our single bonds."}, {"title": "Cis-Trans Z-e Isomer Stability .txt", "text": "So we have the methyl group, the methyl group and our two HS here."}, {"title": "Cis-Trans Z-e Isomer Stability .txt", "text": "Now, one important detail that you must remember about double bonds versus single bonds."}, {"title": "Cis-Trans Z-e Isomer Stability .txt", "text": "Double bonds do not rotate their rigid while single bonds, single covalent bonds are able to rotate."}, {"title": "Cis-Trans Z-e Isomer Stability .txt", "text": "So this bond here will rotate and this bond here will also rotate."}, {"title": "Cis-Trans Z-e Isomer Stability .txt", "text": "So let's suppose that this bond rotates and this bond also rotates."}, {"title": "Cis-Trans Z-e Isomer Stability .txt", "text": "What will happen then?"}, {"title": "Cis-Trans Z-e Isomer Stability .txt", "text": "Well, if these two bonds rotate, look at what happens when they rotate."}, {"title": "Cis-Trans Z-e Isomer Stability .txt", "text": "They will bump and this bumping will cause steric hinderance."}, {"title": "Cis-Trans Z-e Isomer Stability .txt", "text": "This will interfere and destabilize this CIS three hexane."}, {"title": "Cis-Trans Z-e Isomer Stability .txt", "text": "In other words, there is this bumping effect when these two single bonds rotate."}, {"title": "Cis-Trans Z-e Isomer Stability .txt", "text": "And this means or this creates a high energy destabilizing interaction in the CIS compound."}, {"title": "Cis-Trans Z-e Isomer Stability .txt", "text": "What about our trans compound?"}, {"title": "Cis-Trans Z-e Isomer Stability .txt", "text": "Let's suppose we move this ethyl group into or onto the bottom and now we have our transexane."}, {"title": "Cis-Trans Z-e Isomer Stability .txt", "text": "So now no matter how much they rotate, there's no interaction between these destabilizing ethyl groups between these large ethyl groups."}, {"title": "Cis-Trans Z-e Isomer Stability .txt", "text": "And that means the trans isomer is the more stable isomer because it does not have the destabilizing interaction between the two ethyl groups like in the CIS compound."}, {"title": "Cis-Trans Z-e Isomer Stability .txt", "text": "Therefore, it has a lower or more negative enthalpy of formation."}, {"title": "Cis-Trans Z-e Isomer Stability .txt", "text": "There is a difference of about one kilogal per mole of energy between this guy and this compound."}, {"title": "Cis-Trans Z-e Isomer Stability .txt", "text": "And this one is more stable than the CIS because there's no interaction between these two large ethyl groups."}, {"title": "Using a Barometer .txt", "text": "Now, the same way that you could measure the temperature of the atmosphere using a thermometer, you can also measure atmospheric pressure using a barometer."}, {"title": "Using a Barometer .txt", "text": "A barometer can be settled using three things a long cylindrical tube open at one end, and dense liquid, usually mercury, in a cup."}, {"title": "Using a Barometer .txt", "text": "Now, you take the cup, you fill it up with mercury."}, {"title": "Using a Barometer .txt", "text": "You take the tube, you fill that up to the rib of mercury."}, {"title": "Using a Barometer .txt", "text": "You take the tube, flip it upside down, and place it into the cup."}, {"title": "Using a Barometer .txt", "text": "Now, once you place it to the cup, a vacuum is created in this section."}, {"title": "Using a Barometer .txt", "text": "And that's because the force of gravity pulls down on the liquid."}, {"title": "Using a Barometer .txt", "text": "But it will pull down to a certain extent."}, {"title": "Using a Barometer .txt", "text": "And that's because the air molecules found on the outside, such as oxygen molecules, carbon dioxide molecules, nitrogen molecules, exert a certain force on these two sections here on this liquid."}, {"title": "Using a Barometer .txt", "text": "And when the force of these molecules equals the force of the gravity on the liquid, when these two forces equal, it will stop pulling down, and it will level off at some height H. So then you can calculate that height, H, from this point to this point."}, {"title": "Using a Barometer .txt", "text": "And you can use this formula to find the pressure of the atmosphere where pressure is equal to density of liquid times gravitational constant times height H.\nSo let's see what happens when the atmosphere pressure increases."}, {"title": "Using a Barometer .txt", "text": "Suppose you decrease the altitude where you are measuring the pressure, so the pressure increases."}, {"title": "Using a Barometer .txt", "text": "If the pressure increases, then the force will increase."}, {"title": "Using a Barometer .txt", "text": "That's pushing down this liquid."}, {"title": "Using a Barometer .txt", "text": "It will push the liquid down lower and will raise this higher."}, {"title": "Using a Barometer .txt", "text": "So h will increase."}, {"title": "Using a Barometer .txt", "text": "And according to the formula, we see just that."}, {"title": "Using a Barometer .txt", "text": "If the pressure has increased while these two guys are held constant, h will increase."}, {"title": "Using a Barometer .txt", "text": "The same is true for a lower pressure."}, {"title": "Using a Barometer .txt", "text": "Suppose we go higher up to some mountain top."}, {"title": "Using a Barometer .txt", "text": "At this mountaintop, the pressure is lower."}, {"title": "Using a Barometer .txt", "text": "So H will be lower as well, because these two guys are constant."}, {"title": "Using a Barometer .txt", "text": "And that's because if the pressure is lower, the force of gravity will be higher."}, {"title": "Using a Barometer .txt", "text": "And so it will push this level up, and it will lower this level."}, {"title": "Using a Barometer .txt", "text": "Okay?"}, {"title": "Using a Barometer .txt", "text": "So the height, the total height, will be lower."}, {"title": "Using a Barometer .txt", "text": "Now, last thing I want to talk about is this little vacuum here."}, {"title": "Using a Barometer .txt", "text": "Now, remember, this liquid we chose, mercury, will evaporate some of its molecules."}, {"title": "Using a Barometer .txt", "text": "So technically, this isn't a vacuum."}, {"title": "Using a Barometer .txt", "text": "And there are some vapor molecules flowing around or flying around in this area in the space here."}, {"title": "Using a Barometer .txt", "text": "Now, what happens if we increase the vapor pressure here?"}, {"title": "Using a Barometer .txt", "text": "If we increase the vapor pressure, the pressure due to the molecules in the air will push on this section here."}, {"title": "Using a Barometer .txt", "text": "It will decrease this level and decrease the height."}, {"title": "Using a Barometer .txt", "text": "So there will be some discrepancy in the atmospheric pressure if there are molecules found within this section."}, {"title": "Using a Barometer .txt", "text": "So the more volatile the liquid that's used in this section, the higher the bigger pressure is."}, {"title": "Using a Barometer .txt", "text": "And that means the larger the difference from here to here, the lower this section will be."}, {"title": "Using a Barometer .txt", "text": "Now, the same way that you could measure the temperature of the atmosphere using a thermometer, you can also measure atmospheric pressure using a barometer."}, {"title": "Using a Barometer .txt", "text": "A barometer can be semblasing three things a long cylindrical tube open at one end and then select usually mercury and a cup."}, {"title": "Using a Barometer .txt", "text": "Now, you take the cup, you fill it up with mercury."}, {"title": "Using a Barometer .txt", "text": "You take the tube, you fill that up to the rib of mercury."}, {"title": "Using a Barometer .txt", "text": "You take the tube, flip it upside down, and place it into the cup."}, {"title": "Using a Barometer .txt", "text": "Now, once you place it to the cup, a vacuum is created in this section."}, {"title": "Using a Barometer .txt", "text": "And that's because the force of gravity pulls down on the liquid."}, {"title": "Using a Barometer .txt", "text": "But it will pull down to a certain extent."}, {"title": "Using a Barometer .txt", "text": "And that's because the air molecules found on the outside, such as oxygen molecules, carbon dioxide molecules, nitrogen molecules, exert a certain force on these two sections here on this liquid."}, {"title": "Using a Barometer .txt", "text": "And when the force of these molecules equals the force of the gravity on the liquid, when these two forces equal, it will stop pulling down, and it will level off at some height H. So then you can calculate that height H from this point to this point."}, {"title": "Using a Barometer .txt", "text": "And you can use this formula to find the pressure of the atmosphere where pressure is equal to density of liquid times gravitational constant times height H.\nSo let's see what happens when the atmosphere pressure increases."}, {"title": "Using a Barometer .txt", "text": "Suppose you decrease the altitude where you are measuring the pressure, so the pressure increases."}, {"title": "Using a Barometer .txt", "text": "If the pressure increases, then the force will increase."}, {"title": "Using a Barometer .txt", "text": "That's pushing down this liquid."}, {"title": "Using a Barometer .txt", "text": "It will push the liquid down lower and will raise this higher."}, {"title": "Using a Barometer .txt", "text": "So h will increase."}, {"title": "Using a Barometer .txt", "text": "And according to the formula, we see just that."}, {"title": "Using a Barometer .txt", "text": "If the pressure has increased while these two guys are held constant, h will increase."}, {"title": "Using a Barometer .txt", "text": "The same is true for a lower pressure."}, {"title": "Using a Barometer .txt", "text": "Supposedly, go higher up to some mountain top."}, {"title": "Using a Barometer .txt", "text": "At this mountaintop, the pressure is lower."}, {"title": "Using a Barometer .txt", "text": "So H will be lower as well, because these two guys are constant."}, {"title": "Using a Barometer .txt", "text": "And that's because if the pressure is lower, the force of gravity will be higher."}, {"title": "Using a Barometer .txt", "text": "And so it will push this level up, and it will lower this level."}, {"title": "Using a Barometer .txt", "text": "Okay?"}, {"title": "Using a Barometer .txt", "text": "So the height, the total height, will be lower."}, {"title": "Using a Barometer .txt", "text": "Now, last thing I want to talk about is this little vacuum here."}, {"title": "Using a Barometer .txt", "text": "Now, remember, this liquid we chose, mercury, will evaporate some of its molecules."}, {"title": "Using a Barometer .txt", "text": "So, technically, this isn't a vacuum."}, {"title": "Using a Barometer .txt", "text": "And there are some vapor molecules flowing around or flying around in this area in the space here."}, {"title": "Using a Barometer .txt", "text": "Now, what happens if we increase the vapor pressure here?"}, {"title": "Using a Barometer .txt", "text": "If we increase the vapor pressure, the pressure due to the molecules in the air will push on this section here."}, {"title": "Using a Barometer .txt", "text": "It will decrease this level and decrease the height."}, {"title": "Using a Barometer .txt", "text": "So there will be some discrepancy in the atmospheric pressure."}, {"title": "Using a Barometer .txt", "text": "If there are molecules found within this section."}, {"title": "Definition of Temperature .txt", "text": "In this lecture, I will talk to you about the concept of temperature."}, {"title": "Definition of Temperature .txt", "text": "Now, temperature can be defined in many different ways."}, {"title": "Definition of Temperature .txt", "text": "In this video, I've outlined three major definitions of temperature."}, {"title": "Definition of Temperature .txt", "text": "The first definition talks about energy transfer."}, {"title": "Definition of Temperature .txt", "text": "The second definition talks about the ideal gas law."}, {"title": "Definition of Temperature .txt", "text": "And the third definition couples thermal energy or kinetic energy with temperature."}, {"title": "Definition of Temperature .txt", "text": "Now let's go to the first definition."}, {"title": "Definition of Temperature .txt", "text": "Now let's remember what heat is."}, {"title": "Definition of Temperature .txt", "text": "Heat is a transfer of energy from a cold body to a hot body, which means that an energy transfer only occurs when there is a difference in temperature."}, {"title": "Definition of Temperature .txt", "text": "So one way to define temperature is to say that temperature is a property of matter that determines if energy transfer can occur."}, {"title": "Definition of Temperature .txt", "text": "That is, if there is no difference in temperature."}, {"title": "Definition of Temperature .txt", "text": "If the temperature of one object and a second object are the same, no energy transfer due to heat can occur."}, {"title": "Definition of Temperature .txt", "text": "Okay?"}, {"title": "Definition of Temperature .txt", "text": "And that's pretty intuitive."}, {"title": "Definition of Temperature .txt", "text": "Let's look at the second definition, the ideal gas law."}, {"title": "Definition of Temperature .txt", "text": "Well, the ideal gas law tells us that pressure times volume equals number of moles times a constant R times temperature t.\nFrom that, when we keep pressure constant and the number of moles constant, we get Charles Law or v one over t one equals V two over t two."}, {"title": "Definition of Temperature .txt", "text": "And when we graph this, we get the following."}, {"title": "Definition of Temperature .txt", "text": "Suppose we graph it at one ATM, we get a linear relationship."}, {"title": "Definition of Temperature .txt", "text": "If we graph it at three ATM, we also get a linear relationship."}, {"title": "Definition of Temperature .txt", "text": "If we graph it at five at M, we also get a linear relationship."}, {"title": "Definition of Temperature .txt", "text": "Now, at any other temperature, it would also show a linear relationship."}, {"title": "Definition of Temperature .txt", "text": "Now, one thing can be seen from this graph is that at every single temperature, the graph is a set at exactly one point."}, {"title": "Definition of Temperature .txt", "text": "And that one point is right here on the x axis."}, {"title": "Definition of Temperature .txt", "text": "And we can define temperature to be zero Kelvin at this point."}, {"title": "Definition of Temperature .txt", "text": "That is below this, right?"}, {"title": "Definition of Temperature .txt", "text": "It cannot exist."}, {"title": "Definition of Temperature .txt", "text": "No temperature below this can't exist."}, {"title": "Definition of Temperature .txt", "text": "There are only temperatures above absolute zero."}, {"title": "Definition of Temperature .txt", "text": "And that's another way to define temperature, using graphs and using equations."}, {"title": "Definition of Temperature .txt", "text": "So this isn't that intuitive."}, {"title": "Definition of Temperature .txt", "text": "This is more intuitive."}, {"title": "Definition of Temperature .txt", "text": "Now, the third definition is also intuitive."}, {"title": "Definition of Temperature .txt", "text": "The third definition talks about thermal energy or a kinetic energy of a system."}, {"title": "Definition of Temperature .txt", "text": "Now, remember, the kinetic energy is the translational energies plus the rotational energies plus the vibrational energies of a system, right?"}, {"title": "Definition of Temperature .txt", "text": "So when we talk about fluids, we talk about mainly translational and rotational energies."}, {"title": "Definition of Temperature .txt", "text": "And we can formulate this formula here, which basically says translational energy plus rotational energy equals three over two times the constant K times temperature."}, {"title": "Definition of Temperature .txt", "text": "So from this equation, we see that if we increase temperature, we increase translational energy or the speed, and we increase rotational energy or the torque for solace."}, {"title": "Definition of Temperature .txt", "text": "However, there's really no translational energies or rotational energies at low temperature."}, {"title": "Definition of Temperature .txt", "text": "So we can't really have a relation between temperature and kinetic energy at low temperatures."}, {"title": "Definition of Temperature .txt", "text": "Now, at high temperatures, solids actually begin to translate and rotate slightly."}, {"title": "Definition of Temperature .txt", "text": "So at high temperatures, we can't use this formula for solids."}, {"title": "Definition of Temperature .txt", "text": "But what we could say is that for high temperatures, as temperature increases, so does the kinetic energy."}, {"title": "Definition of Temperature .txt", "text": "Now, one last thing I want to mention is from this definition, I said that temperature is a property."}, {"title": "Definition of Temperature .txt", "text": "Now, more specifically, temperature is an intensive property."}, {"title": "Definition of Temperature .txt", "text": "Now remember, when you divide an extensive property by another extensive property, you get an intensive property."}, {"title": "Definition of Temperature .txt", "text": "And I mentioned this in my previous video, okay?"}, {"title": "Definition of Temperature .txt", "text": "And we see this from this fact here."}, {"title": "Definition of Temperature .txt", "text": "Kinetic energy, which is an extensive property."}, {"title": "Definition of Temperature .txt", "text": "If you divide it by the number of moles, which is also an extensive property, you get temperature, right?"}, {"title": "Definition of Temperature .txt", "text": "And so extensive property divided by an extensive property gives you an intensive property."}, {"title": "Definition of Temperature .txt", "text": "And so that's why temperature must be an intensive property."}, {"title": "Definition of Temperature .txt", "text": "Which basically means that no matter how large the system gets or how small the system gets, the temperature will remain the same."}, {"title": "Solution formation and heat of solution .txt", "text": "Solution formation is a formation of intermolecular bonds between two or more different compounds down in the same mixture."}, {"title": "Solution formation and heat of solution .txt", "text": "Now let's remember what intermolecular bonds are."}, {"title": "Solution formation and heat of solution .txt", "text": "Intermolecular bonds are non COBALTING forces that hold two or more different molecules in place."}, {"title": "Solution formation and heat of solution .txt", "text": "Suppose we have a single molecule."}, {"title": "Solution formation and heat of solution .txt", "text": "What holds that molecule in place?"}, {"title": "Solution formation and heat of solution .txt", "text": "Well, covalent bonds or the shared electrons between different atoms of that same molecule hold that molecule in place."}, {"title": "Solution formation and heat of solution .txt", "text": "What holds a bunch of different molecules in place?"}, {"title": "Solution formation and heat of solution .txt", "text": "Well, noncovalent forces such as dipole forces or lumpin forces hold these guys in place."}, {"title": "Solution formation and heat of solution .txt", "text": "And these forces are called intermolecular forces."}, {"title": "Solution formation and heat of solution .txt", "text": "So intermocular forces are simply non covalent bonds between different molecules."}, {"title": "Solution formation and heat of solution .txt", "text": "They hold different molecules in place."}, {"title": "Solution formation and heat of solution .txt", "text": "Now what are solutions?"}, {"title": "Solution formation and heat of solution .txt", "text": "Solutions are mixtures of at least two compounds."}, {"title": "Solution formation and heat of solution .txt", "text": "Suppose we had a Beaker A with compound X and Baker B with compound Y?"}, {"title": "Solution formation and heat of solution .txt", "text": "Now suppose we wanted to make a solution out of compound X and Y."}, {"title": "Solution formation and heat of solution .txt", "text": "So we mix them."}, {"title": "Solution formation and heat of solution .txt", "text": "What would have to happen before a solution is formed?"}, {"title": "Solution formation and heat of solution .txt", "text": "So by definition, we said solution formation is a formation of intermolecular bonds between X and Y."}, {"title": "Solution formation and heat of solution .txt", "text": "Well, before a bond is formed between X and Y, the bonds between the XS and the YS must break."}, {"title": "Solution formation and heat of solution .txt", "text": "So before X and Y forms a solution, intermolecular bonds between compound X and intermolecular bonds between compound Y must break."}, {"title": "Solution formation and heat of solution .txt", "text": "Once all these intermocular bonds break, then intermolecular bonds between compounds X and Y must form."}, {"title": "Solution formation and heat of solution .txt", "text": "Now remember, the breaking of a bond is endothermic."}, {"title": "Solution formation and heat of solution .txt", "text": "So these guys are endothermic."}, {"title": "Solution formation and heat of solution .txt", "text": "The formation of bonds is exothermic or energy is released."}, {"title": "Solution formation and heat of solution .txt", "text": "Now, from another lecture we saw that change in enthalpy is equal to a change in internal energy plus PD work done or the work done by the system on the environment to create that system."}, {"title": "Solution formation and heat of solution .txt", "text": "We also saw that if pressure is held constant and the number of moles is held constant, the change in volume is zero."}, {"title": "Solution formation and heat of solution .txt", "text": "If the change in volume is zero, this term becomes zero."}, {"title": "Solution formation and heat of solution .txt", "text": "So we can say change in enthalpy is simply equal to change in internal energy."}, {"title": "Solution formation and heat of solution .txt", "text": "Remember, when bonds are broken, reaction is endothermic."}, {"title": "Solution formation and heat of solution .txt", "text": "Okay?"}, {"title": "Solution formation and heat of solution .txt", "text": "Energy is required to break a bond."}, {"title": "Solution formation and heat of solution .txt", "text": "So the enthalpy of this system, of this guy is positive."}, {"title": "Solution formation and heat of solution .txt", "text": "Enthalpy change of this guy is also positive."}, {"title": "Solution formation and heat of solution .txt", "text": "Now, when bonds are formed, energy is released, they're exothermic."}, {"title": "Solution formation and heat of solution .txt", "text": "So the formation of Ynex is negative."}, {"title": "Solution formation and heat of solution .txt", "text": "Now if we add all these guys up, we get something called heat of solution."}, {"title": "Solution formation and heat of solution .txt", "text": "And heat of solution can tell you if the solution formation is exothermic or endothermic."}, {"title": "Solution formation and heat of solution .txt", "text": "Now if this guy is negative, it's exothermic."}, {"title": "Solution formation and heat of solution .txt", "text": "And bonds formed are stronger or more stable than the bonds broken."}, {"title": "Solution formation and heat of solution .txt", "text": "So this bond between X and Y is greater or is stronger and more stable than that bond or this bond."}, {"title": "Solution formation and heat of solution .txt", "text": "If the heat of solution is positive, the bonds formed are weaker than the bonds broken."}, {"title": "Solution formation and heat of solution .txt", "text": "So the bond here is weaker and less stable than the bond here."}, {"title": "Solution formation and heat of solution .txt", "text": "Or here."}, {"title": "Solution formation and heat of solution .txt", "text": "Now, entropy will never tell you if a solution is spontaneous."}, {"title": "Solution formation and heat of solution .txt", "text": "Likewise, heat of solution does not tell you if a reaction is spontaneous."}, {"title": "Solution formation and heat of solution .txt", "text": "Now, remember, only entropy dictates spontaneity."}, {"title": "Solution formation and heat of solution .txt", "text": "Luckily, solutions usually increase in entropy, and entropy determine spontaneity."}, {"title": "Solution formation and heat of solution .txt", "text": "Now, under right conditions, solutions are usually spontaneous."}, {"title": "Solution formation and heat of solution .txt", "text": "And that's because entropy is increased."}, {"title": "Solution formation and heat of solution .txt", "text": "It's not because the reaction is exothermic."}, {"title": "Solution formation and heat of solution .txt", "text": "And, in fact, endothermic reactions with an increase in entropy could be spontaneous."}, {"title": "Effective Nuclear Charge and the Shielding Effect .txt", "text": "Recall that what actually holds a noun together are the electrostatic forces felt by the electrons and the protons in the nucleus."}, {"title": "Effective Nuclear Charge and the Shielding Effect .txt", "text": "And this electrostatic force can be described by Coulomb's law or Coulomb's equation that states the following."}, {"title": "Effective Nuclear Charge and the Shielding Effect .txt", "text": "The force on either of the proton or the electron is given by k, a constant times q one, the q, or the charge of the protons times q two, the charge, the electrons divided by the distance between them squared."}, {"title": "Effective Nuclear Charge and the Shielding Effect .txt", "text": "And what Coulomb's law does, it describes the force and electron experiences due to the pull of the proton nucleus."}, {"title": "Effective Nuclear Charge and the Shielding Effect .txt", "text": "So let's look at two atoms, and let's compare these guys."}, {"title": "Effective Nuclear Charge and the Shielding Effect .txt", "text": "First, let's look at hydrogen, and then let's look at helium."}, {"title": "Effective Nuclear Charge and the Shielding Effect .txt", "text": "Well, recall that hydrogen has exactly one proton and one neutron in its neutral state."}, {"title": "Effective Nuclear Charge and the Shielding Effect .txt", "text": "And that means we can find the electrostatic force or the pull on this electron due to this proton by simply applying our coulombs equation."}, {"title": "Effective Nuclear Charge and the Shielding Effect .txt", "text": "And this guy states that our force due to this electron or on this electron due to this proton is given by k, a constant times the charge of our proton, times the charge of our electron divided by our distance r between them squared."}, {"title": "Effective Nuclear Charge and the Shielding Effect .txt", "text": "And this is the force that this guy feels due to this guy and also the force that this proton feels due to this electron."}, {"title": "Effective Nuclear Charge and the Shielding Effect .txt", "text": "Now, note that their forces are negative, but they have the same magnitude."}, {"title": "Effective Nuclear Charge and the Shielding Effect .txt", "text": "So now let's look at helium."}, {"title": "Effective Nuclear Charge and the Shielding Effect .txt", "text": "Remember, the outermost electrons are the electrons that will be pulled away."}, {"title": "Effective Nuclear Charge and the Shielding Effect .txt", "text": "The inner electrons found on lower energy levels will not be pulled away first."}, {"title": "Effective Nuclear Charge and the Shielding Effect .txt", "text": "So in helium, we now have two protons and two electrons."}, {"title": "Effective Nuclear Charge and the Shielding Effect .txt", "text": "So our nucleus is composed of two protons, and our shells are composed of one electron each."}, {"title": "Effective Nuclear Charge and the Shielding Effect .txt", "text": "So now we have an inner shell and an outermost shell."}, {"title": "Effective Nuclear Charge and the Shielding Effect .txt", "text": "And recall that electrons on the outermost shell will be pulled away."}, {"title": "Effective Nuclear Charge and the Shielding Effect .txt", "text": "So this is the electron we have to worry about."}, {"title": "Effective Nuclear Charge and the Shielding Effect .txt", "text": "This is the electron that will be pulled away."}, {"title": "Effective Nuclear Charge and the Shielding Effect .txt", "text": "So if we calculate the force that this guy experiences due to this proton nucleus, we'll see a discrepancy."}, {"title": "Effective Nuclear Charge and the Shielding Effect .txt", "text": "And this discrepancy comes from something called the shielding effect."}, {"title": "Effective Nuclear Charge and the Shielding Effect .txt", "text": "Now, this innermost atom or this innermost electron creates a shielding effect."}, {"title": "Effective Nuclear Charge and the Shielding Effect .txt", "text": "In other words, inner electrons surrounding our nucleus shield the outermost electron from some of that charge due to our protons decreasing the net pull of the nucleus on our outermost electron."}, {"title": "Effective Nuclear Charge and the Shielding Effect .txt", "text": "Now, the final amount of charge felt by this outermost electron due to our proton nucleus is called the effective nuclear charge."}, {"title": "Effective Nuclear Charge and the Shielding Effect .txt", "text": "In other words, because there is a second electron found even closer to our nucleus, that means the charge that this guy will feel due to this proton nucleus will be less than what it would feel if this electron wasn't here."}, {"title": "Effective Nuclear Charge and the Shielding Effect .txt", "text": "That means if we use the same exact formula for Coulomb's law for this guy, we'll get this result."}, {"title": "Effective Nuclear Charge and the Shielding Effect .txt", "text": "In other words, the force that this guy feels this charge due to our proton nucleus."}, {"title": "Effective Nuclear Charge and the Shielding Effect .txt", "text": "This guy divided by R squared times K will be greater than the actual force that this guy feels."}, {"title": "Effective Nuclear Charge and the Shielding Effect .txt", "text": "Why?"}, {"title": "Effective Nuclear Charge and the Shielding Effect .txt", "text": "Well, because some of its positive charge will be dissipated to this electron."}, {"title": "Effective Nuclear Charge and the Shielding Effect .txt", "text": "So that means our final effective nuclear charge will be less."}, {"title": "Effective Nuclear Charge and the Shielding Effect .txt", "text": "So the way we find our effective nuclear charge is using the following formula."}, {"title": "Effective Nuclear Charge and the Shielding Effect .txt", "text": "Our effective nuclear charge given by ZF equals to the nuclear charge or the actual nuclear charge of our proton nucleus minus the average number of electrons separating our outermost electron and our proton nucleus."}, {"title": "Effective Nuclear Charge and the Shielding Effect .txt", "text": "And we see that for helium, if our nuclear charge on our proton nucleus is two, then this guy actually feels a charge of 1.69, because we're subtracting the charge that this guy experiences."}, {"title": "Effective Nuclear Charge and the Shielding Effect .txt", "text": "So at the end, this atomos electron will experiences on average less pole."}, {"title": "Effective Nuclear Charge and the Shielding Effect .txt", "text": "So let's compare the effective nuclear charge of the following two atoms."}, {"title": "Effective Nuclear Charge and the Shielding Effect .txt", "text": "Let's look at lithium and Beryllium."}, {"title": "Effective Nuclear Charge and the Shielding Effect .txt", "text": "Now, notice that Beryllium is one guy over to the right on their periodic table."}, {"title": "Effective Nuclear Charge and the Shielding Effect .txt", "text": "That means it has four protons and four electrons, while lithium has three protons and three electrons."}, {"title": "Effective Nuclear Charge and the Shielding Effect .txt", "text": "Let's compare the atomic structure."}, {"title": "Effective Nuclear Charge and the Shielding Effect .txt", "text": "So, the atomic structure of lithium is the following."}, {"title": "Effective Nuclear Charge and the Shielding Effect .txt", "text": "Two of its electrons are found in the innermost shell, the one s shell."}, {"title": "Effective Nuclear Charge and the Shielding Effect .txt", "text": "And one electron, because it only has three electrons, is found in the outermost two s shell."}, {"title": "Effective Nuclear Charge and the Shielding Effect .txt", "text": "Now, let's look at the comic structure of Beryllium."}, {"title": "Effective Nuclear Charge and the Shielding Effect .txt", "text": "This guy has one extra electron or one more electron than lithium."}, {"title": "Effective Nuclear Charge and the Shielding Effect .txt", "text": "Now, that means that it also just like lithium has two electrons on the one s in it orbital."}, {"title": "Effective Nuclear Charge and the Shielding Effect .txt", "text": "But now, because it has an extra electron, it has two electrons in the outermost two s orbital."}, {"title": "Effective Nuclear Charge and the Shielding Effect .txt", "text": "So the ratio in lithium of inner electrons to outer electrons is two to one, while the ratio of inner to outer electrons in Beryllium is two to two."}, {"title": "Effective Nuclear Charge and the Shielding Effect .txt", "text": "So the ratio is greater in this guy."}, {"title": "Effective Nuclear Charge and the Shielding Effect .txt", "text": "The significance of this is the following."}, {"title": "Effective Nuclear Charge and the Shielding Effect .txt", "text": "Because our ratio of inner to outer is greater, that means the inner electrons will take away or shield more charge."}, {"title": "Effective Nuclear Charge and the Shielding Effect .txt", "text": "So lithium will experience a strong shielding effect due to these inner electrons."}, {"title": "Effective Nuclear Charge and the Shielding Effect .txt", "text": "So this single hour electron will not experience as much charge as it would if these guys weren't here."}, {"title": "Effective Nuclear Charge and the Shielding Effect .txt", "text": "Now, let's compare this guy."}, {"title": "Effective Nuclear Charge and the Shielding Effect .txt", "text": "Notice that in this guy we have one more electron in our outer shell."}, {"title": "Effective Nuclear Charge and the Shielding Effect .txt", "text": "And what that basically means is that because our ratio of eight to outer is smaller, that means this shielding effect will not be as great, because now we have an extra electron floating around our shell."}, {"title": "Effective Nuclear Charge and the Shielding Effect .txt", "text": "So these guys will experience more charge than Dixon electron on the lithium."}, {"title": "Effective Nuclear Charge and the Shielding Effect .txt", "text": "And what that means is that these two electrons will be pulled closer to the nucleus than here."}, {"title": "Effective Nuclear Charge and the Shielding Effect .txt", "text": "And therefore the radius of this atom will be smaller than the radius of this atom."}, {"title": "Effective Nuclear Charge and the Shielding Effect .txt", "text": "And that's because of the following."}, {"title": "Effective Nuclear Charge and the Shielding Effect .txt", "text": "They both have a one s and a two s orbital."}, {"title": "Effective Nuclear Charge and the Shielding Effect .txt", "text": "So technically, their radius should be the same."}, {"title": "Effective Nuclear Charge and the Shielding Effect .txt", "text": "But it's not."}, {"title": "Effective Nuclear Charge and the Shielding Effect .txt", "text": "It's smaller in this guy because it has a weaker shielding effect."}, {"title": "Effective Nuclear Charge and the Shielding Effect .txt", "text": "In other words, the two electrons found on the outermost atom on the outermost shell experience more charge and so therefore are pulled closer."}, {"title": "Effective Nuclear Charge and the Shielding Effect .txt", "text": "So, once again, the shielding effect is not as great in Beryllium as it is in lithium because the extra electron in Beryllium is added to the same energy level."}, {"title": "Effective Nuclear Charge and the Shielding Effect .txt", "text": "The same two S orbital."}, {"title": "Effective Nuclear Charge and the Shielding Effect .txt", "text": "And so that means because there's more charge on the electron on the outermost shell, it will experience more pull, and so it will be pulled closer, therefore increasing the effective nuclear charge on the beryllium versus the lithium."}, {"title": "Effective Nuclear Charge and the Shielding Effect .txt", "text": "In other words, there will be a greater effective nuclear charge in Beryllium than in lithium because of this extra electrons."}, {"title": "Effective Nuclear Charge and the Shielding Effect .txt", "text": "And in fact, this is the trend that we see as we go from the left to the right across the period, our nuclear that the charge increases, decreasing our radius."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "In this lecture, I'd like to talk about the concept of electron configuration."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "But before we get into that, it's really important to talk about the following principle known as the AFP principle."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "Now, this principle will help us explain electron configuration."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "Now, what this principle states is the following."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "Whenever an atom adds a new proton to create a new atom element, it must also add another electron to neutralize that extra charge that comes from that extra proton."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "So the problem is the following whenever we add a proton, we know exactly where our proton goes."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "That proton goes into the nucleus along with all the other protons."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "What about our electrons?"}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "We have options as to where to place those electrons."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "Because we have many different shells, we have many different subshells and we have made different orbitals within our subshells."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "So."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "Luckily, nature always tends to form the lowest possible energy state."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "Therefore, whenever we add electrons to our atom, that electron will go into the lowest possible subshell."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "Lowest possible energy subshell."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "So let's examine the following concepts, and I state the following as electrons move further from the nucleus, our energy level will increase."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "And this is true."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "Now let's examine why it's true."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "Well, let's look at the following illustration."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "Suppose we have a proton now, a nucleus."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "And this is an electron."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "A distance."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "R away from it."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "Now Coulomb's law will give us some force that this guy feels due to this electron."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "And then it will also give us the same force, except in negative direction, that this guy feels due to this proton."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "Now, my question is, how do we get this electron not a distance our way, but a distance to our way?"}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "In other words, how do we move this electron from this guy from this distance to this distance?"}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "Well, remember, if this is a positive force and this is a negative force, these guys are tracting."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "They want to come close."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "So in order for me to move this guy a distance R here a distance two R from our nucleus."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "That means I have to do work on that electron."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "So if We Consider Our Proton And our electron a system, that means I have to do work on my system to move this electron a distance r away from this electron, right?"}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "So that means work must be done on our system."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "And because work is a transfer of energy, energy must be transferred into our system."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "So our overall energy of our system increases as the electron moves away from our nucleus."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "And that's exactly why placing electrons further away from our nucleus will increase the energy of our system."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "That's exactly why nature tends to place electrons as close to our atom, as close to our nucleus as possible."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "Because placing it further away increases the energy of our system."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "And nature tends to take the lowest energy state."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "So that's exactly why when we look at the principal quantum numbers as our principal quantum numbers increase as we go from n equals one to n equals two to n equals three, or from Orbital S P to D. Our energy will increase as we go down this table."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "So now let's talk about electron configuration."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "Electron configuration is simply a systematic approach to representing and showing exactly where our electrons are placed within any given atom."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "In other words, in which shells or in which subshells are our electrons down?"}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "So let's look at the simplest atom."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "The h atom."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "The H Atom has one proton and one electron."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "The proton is the nucleus."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "The electron is down, orbiting our nucleus."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "Now, what are the Quantum numbers of this electron?"}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "Well, this guy has the first principal level."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "The first principal quantum number, or N equals one."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "And that means if N equals one, our second quantum number, our L must be zero."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "And if l is zero, that means our third quantum number, the orbital in which our electron is located is the s orbital."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "So to represent this in an electron configuration way, we simply do the following."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "We put a coefficient in front of our S. So the Wand represents our shell, our principal quantum number."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "Our S represents our subshell."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "And at the same time, it also represents our orbital in which our electron is in."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "The SuperScript of one represents the number of electrons."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "So we have one electron."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "So we have a SuperScript of one."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "So this Is The Electron Configuration for this atom."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "For the h atom."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "Now, any atom or any element on the periodic table has an electron configuration."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "So let's look at another one."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "Let's look at oxygen."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "Oxygen has an atomic number of eight."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "And that means in its neutral state, it has eight electrons."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "So let's look at its electron configuration."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "Now, notice that n equals One."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "It could fit two electrons."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "Because when n equals one, our l equals zero."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "And we only have one orbital, the S orbital."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "So we can place the maximum of two electrons into any orbital."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "So we can place two electrons into shell level."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "N equals one."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "How about N equals two?"}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "Well, n equals two has a maximum of two to the two."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "So maximum of four orbitals."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "That means if we have four orbitals, I have an s orbital and three p orbitals."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "Right?"}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "So I could put a maximum of eight electrons into my N equals two energy level into my N equals two shell."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "So I place two electrons into my s orbital."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "This guy's my s orbital."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "And then I could put six electrons into my three p orbitals."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "So 1234, I put Four, because I only have four left over."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "So now let's look at the electron configuration for our oxygen."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "In our principal quantum number one."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "N equals one."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "We have only the X orbital."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "So we place two electrons here."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "So one s, two."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "And now N equals two."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "We have an S and the three P's."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "And that means we first place two electrons into our S.\nSo two F, two."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "And then we distribute electrons into our piece."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "And we have three P's."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "So we start by putting one in each."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "And I'll explain in a little bit why we put one here, one here, one here, and then one here."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "And not two here and two here and none here."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "I'll explain why in a second."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "Now, so I place one here, one here, one here, and then I place my fourth one into my X."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "So we can also represent this guy in the following way."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "We simply erase all these X's as ZS and simply say two P and we place a four on top."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "Now, whenever we do this, we make the assumption that you understand the fact that this is not a single orbital but this is actually three orbitals."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "Because if this was a single orbital, the four would not make sense because you could only place the maximum of two electrons into any orbital according to the Pole Exclusion Principle."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "So that's the electron configuration."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "One."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "F two."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "Two."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "F two."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "Two."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "P four."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "Since oxygen has a maximum of eight electrons, that means two plus two plus four eight electrons."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "So this makes sense."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "So every atom on the table, every element has its own electron configuration."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "Now, let's look at sodium."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "Sodium has the following electron configuration, right?"}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "It has eleven electrons in its neutral state."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "How about neon?"}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "Neon has ten electrons."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "It has a perfect configuration."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "Every single orbital is completely filled."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "And remember, every atom on a table wants to become a noble gas."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "So every atom wants to become or wants to take the electron configuration of a noble gas."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "And Neon is, in fact, a noble gas."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "Another way representing electro configurations are using noble gas configurations."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "Notice that one S, two, two S two and two P, six is identical to one S Two, two S two and two P six of Neon."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "So we can replace this whole guy simply with neon."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "And these brackets simply mean the electron configuration of Neon."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "And then we add this guy three S one."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "And this means this is the electron configuration of our sodium, right?"}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "Because sodium has one more electron than neon."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "That electron goes into the three S one energy level."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "Now, the ground state of any atom represents its lowest energy state."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "This is the ground state of sodium."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "This is the ground state of hydrogen, and this is the ground state of oxygen."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "Now, when atoms go from a ground state to an excited state, what that means is they form ions or they form excited state atoms."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "And that simply means electrons jump to a higher state."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "And we'll talk more about that when we'll talk about the photoelectric effect."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "So one important aspect of electron configuration must be understood."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "Electron configuration doesn't necessarily have to order things from lowest energy to highest energy."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "Although that's usually the case, that doesn't have to happen."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "In other words, let's look at the following important facts."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "So four S that energy level is at a lower energy than three D, and five S is at a lower energy level than four D.\nAnd this holds for six S and 5D as well."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "Now, these things you just have to simply remember."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "Now, if we look at the electron configuration for Bromine, which has 35 35 protons and 35 electrons, we see the following electron configuration."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "Now, this guy makes sense because one S comes before two S and two S comes before two P and two P comes before three S, and three S comes before three P. In other words, this goes from lowest energy level to highest energy level."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "And since we just said that four S is at a lower energy level than 3D, it would make sense to place the four S two before the this would be the correct election configuration if you're actually ordering from lowest energy level to highest energy level."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "But this doesn't have to be the case."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "In other words, if I flip these guys, that isn't wrong."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "That's allowed."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "That's allowed to happen."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "And that's because electron configuration doesn't necessitate that you have to order them from lowest energy to highest energy."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "Although, if in a question and asks you for the proper electron configuration that order things from lowest to highest, then that has to happen."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "Then this is the proper electron configuration."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "So ions also can be represented using electron configuration."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "For example, let's look at sodium plus has eleven protons and ten elections."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "So in order to write the electric configuration for this guy, we simply take away one electron from the highest energy level."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "So in this case, it would be one S, two two S, two two P, six."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "And we took out one electron from the three S, one orbital, so that that guy disappeared."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "Now, if we make this guy into an ion, right?"}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "Let's say we make it into BR plus ion, we take one electron away."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "That means we take it away from the highest energy level."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "That means we take it away from four P.\nIf we want to add one electron and make this into an anion BR negative, we add an electron and we add the electron electron to the highest energy level, four P five."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "So if this guy gets four P six."}, {"title": "Aufbau Principle and Electron Configuration .txt", "text": "If this guy is BR minus."}, {"title": "Real Gases and van der waals equation .txt", "text": "So far we have only spoken about the way ideal gas molecules behave."}, {"title": "Real Gases and van der waals equation .txt", "text": "We still haven't spoken about how actual or real gas molecules behave."}, {"title": "Real Gases and van der waals equation .txt", "text": "Now, recall that any ideal gas molecule will behave accordingly with the kinetic molecular theory which makes a few important assumptions."}, {"title": "Real Gases and van der waals equation .txt", "text": "Now, in this lecture, we're going to look at the way real gas gas molecules behave and which assumptions are broken down and under which conditions."}, {"title": "Real Gases and van der waals equation .txt", "text": "So on the conditions of standard temperature of zero Celsius and standard pressure of one ATM we can use the ideal gas law to solve problems and to figure out how gas molecules behave."}, {"title": "Real Gases and van der waals equation .txt", "text": "Now, under conditions of high pressure of about 1000 ATM and low temperatures the ideal gas law breaks down meaning our gas molecules no longer behave accordingly with this law."}, {"title": "Real Gases and van der waals equation .txt", "text": "And we can't use this law to solve any form of problem."}, {"title": "Real Gases and van der waals equation .txt", "text": "Now, let's see why this happens and let's see what breaks down."}, {"title": "Real Gases and van der waals equation .txt", "text": "So suppose we have this system in which we have nine molecules and this system is under constant temperature but our pressure is one ATM."}, {"title": "Real Gases and van der waals equation .txt", "text": "Now, suppose we go from this system to a much smaller system."}, {"title": "Real Gases and van der waals equation .txt", "text": "So we decrease volume and we increase pressure but our temperature remains constant."}, {"title": "Real Gases and van der waals equation .txt", "text": "So let's go back to this system, this system which was at standard temperature and pressure, these two values our distance between any two molecules was much larger than the distance or the size of the actual molecule itself."}, {"title": "Real Gases and van der waals equation .txt", "text": "So that means we can use the kinetic theory to approximate how this behaves."}, {"title": "Real Gases and van der waals equation .txt", "text": "Because if the distance is far then we can assume the volume of the molecules to be very, very small."}, {"title": "Real Gases and van der waals equation .txt", "text": "And since they're far away, we can assume they don't attract or repel each other."}, {"title": "Real Gases and van der waals equation .txt", "text": "However, when we get to this state what happens here at high temperatures?"}, {"title": "Real Gases and van der waals equation .txt", "text": "Suppose this is 1000 ATM and still zero Celsius."}, {"title": "Real Gases and van der waals equation .txt", "text": "So our volume has decreased tremendously and our pressure has increased but temperature remains the same."}, {"title": "Real Gases and van der waals equation .txt", "text": "So at very high pressures the distance between any two molecules is approximately the same as the size of the molecule itself."}, {"title": "Real Gases and van der waals equation .txt", "text": "Now, and I claim under this condition the kinetic theory breaks down."}, {"title": "Real Gases and van der waals equation .txt", "text": "So let's see, what about the kinetic theory that breaks down in this system?"}, {"title": "Real Gases and van der waals equation .txt", "text": "Well, now, the molecules are very close to each other."}, {"title": "Real Gases and van der waals equation .txt", "text": "They're so close, in fact, that they will attract each other and repel each other."}, {"title": "Real Gases and van der waals equation .txt", "text": "So the forces that we spoke about before that we neglected."}, {"title": "Real Gases and van der waals equation .txt", "text": "Now we have to take them into consideration."}, {"title": "Real Gases and van der waals equation .txt", "text": "And these forces follow."}, {"title": "Real Gases and van der waals equation .txt", "text": "Coulomb's law means that if our distance decreases, our force increases."}, {"title": "Real Gases and van der waals equation .txt", "text": "So if this one's positive and this one's negative they will attract each other according to Coulomb's law."}, {"title": "Real Gases and van der waals equation .txt", "text": "So now one of the assumptions of the kinetic theory breaks down namely, the electrostatic forces."}, {"title": "Real Gases and van der waals equation .txt", "text": "Electrostatic forces cannot be neglected when pressures are very high."}, {"title": "Real Gases and van der waals equation .txt", "text": "Now, let's look at the volume."}, {"title": "Real Gases and van der waals equation .txt", "text": "Let's take this picture and zoom in."}, {"title": "Real Gases and van der waals equation .txt", "text": "This is what we get."}, {"title": "Real Gases and van der waals equation .txt", "text": "Notice that the space in between the molecules is approximately the same or has the same volume as the molecules themselves."}, {"title": "Real Gases and van der waals equation .txt", "text": "Now, the volume can no longer be neglected."}, {"title": "Real Gases and van der waals equation .txt", "text": "So we can say the volume is zero because now the molecules actually take up a lot of space much more than in this picture."}, {"title": "Real Gases and van der waals equation .txt", "text": "And that means the second assumption in our kinetic theory also breaks down."}, {"title": "Real Gases and van der waals equation .txt", "text": "Namely, volume is no longer zero."}, {"title": "Real Gases and van der waals equation .txt", "text": "So we see that in extreme conditions of high pressure our ideal gas law no longer holds."}, {"title": "Real Gases and van der waals equation .txt", "text": "Now let's see why."}, {"title": "Real Gases and van der waals equation .txt", "text": "Under low temperatures the ideal gas law also breaks down."}, {"title": "Real Gases and van der waals equation .txt", "text": "Well, if we're at low temperatures that means each molecule has a smaller kinetic energy and therefore it's traveling with a smaller velocity."}, {"title": "Real Gases and van der waals equation .txt", "text": "And therefore, they will all drop to the bottom of the container and they will collect and get very close."}, {"title": "Real Gases and van der waals equation .txt", "text": "And if they're close, that means they're feeling electrostatic forces."}, {"title": "Real Gases and van der waals equation .txt", "text": "And so our kinetic theory also breaks down on the low temperatures."}, {"title": "Real Gases and van der waals equation .txt", "text": "Now let's compare the pressure of ideal and real systems."}, {"title": "Real Gases and van der waals equation .txt", "text": "Now, for the pressure of an ideal system, remember they're not feeling electrostatic forces and that means they hit the wall of the container and they're not attracted or repelled by other molecules."}, {"title": "Real Gases and van der waals equation .txt", "text": "For real situations, for real gases, the pressure is less."}, {"title": "Real Gases and van der waals equation .txt", "text": "Well, why is it less?"}, {"title": "Real Gases and van der waals equation .txt", "text": "Well, when the molecule in the real gas travels it's attracted by other molecules."}, {"title": "Real Gases and van der waals equation .txt", "text": "And that means if it's attracted by other molecules if it's pulled by the other molecules it will hit the wall with less force and therefore, a smaller pressure will result."}, {"title": "Real Gases and van der waals equation .txt", "text": "That means for ideal pressures, ideal pressures are higher than real pressures."}, {"title": "Real Gases and van der waals equation .txt", "text": "Likewise, let's examine the conditions for volume of ideal versus volume of real."}, {"title": "Real Gases and van der waals equation .txt", "text": "Now, the volume of ideal is less than volume of real because when you're taken into consideration the volume of real gases you're taking into consideration the volume of the molecules."}, {"title": "Real Gases and van der waals equation .txt", "text": "And that means the volume will be plus the volume of the molecules."}, {"title": "Real Gases and van der waals equation .txt", "text": "And so the volume of real gases will be greater."}, {"title": "Real Gases and van der waals equation .txt", "text": "So now let's see what the gas law is for real gases."}, {"title": "Real Gases and van der waals equation .txt", "text": "So recall that the ideal gas law states that pressure of the ideal system times volume of ideal system gives you NRT."}, {"title": "Real Gases and van der waals equation .txt", "text": "And now notice that in a real system and an ideal system this NRT remains the same."}, {"title": "Real Gases and van der waals equation .txt", "text": "This remains a constant."}, {"title": "Real Gases and van der waals equation .txt", "text": "Because if we're talking about the same temperature our T in both ideal and non ideal conditions stays the same."}, {"title": "Real Gases and van der waals equation .txt", "text": "Our R remains a constant and our number of moles does not change."}, {"title": "Real Gases and van der waals equation .txt", "text": "So in both ideal and non ideal systems this guy remains constant."}, {"title": "Real Gases and van der waals equation .txt", "text": "The only thing that changes is pressure and volume."}, {"title": "Real Gases and van der waals equation .txt", "text": "And so suppose we have P ideal and V ideal."}, {"title": "Real Gases and van der waals equation .txt", "text": "Now, from this information we know that our P real is smaller than our P ideal."}, {"title": "Real Gases and van der waals equation .txt", "text": "And that means we have to add some term to our P real to equate that to our P. Likewise, our Vreal is larger than the ideal and that's why we have to subtract some term from it, some term Y to get the ideal."}, {"title": "Real Gases and van der waals equation .txt", "text": "And so, from experiments, scientists found out what this X and what this Y was."}, {"title": "Real Gases and van der waals equation .txt", "text": "This X is N squared times A over V. Two this Y is N times B."}, {"title": "Real Gases and van der waals equation .txt", "text": "Now, an is simply number of moles, and B is volume a and B are constants that depend on the gas being used."}, {"title": "Real Gases and van der waals equation .txt", "text": "And so they're different for different gases."}, {"title": "Real Gases and van der waals equation .txt", "text": "Now, once again, the reason we have this guy, the reason we're adding this guy to P real is because P real is smaller than P ideal."}, {"title": "Real Gases and van der waals equation .txt", "text": "Likewise, the reason we're subtracting this guy from Vreal is because when we're talking about Vreal or volume of real systems, we're taking into consideration in the volume of the actual molecules."}, {"title": "Real Gases and van der waals equation .txt", "text": "And so vitall is less, because in Vidal, we're not taking the volume of the molecules into consideration."}, {"title": "Real Gases and van der waals equation .txt", "text": "And this formula is known as Vanderwal Equation."}, {"title": "Conjugate Acid-Base Pairs .txt", "text": "In this lecture we're going to talk about the concept of conjugate acidbased pairs."}, {"title": "Conjugate Acid-Base Pairs .txt", "text": "So whenever we have an acid that donates an H plus ion to a base, a new base and a new acid are formed."}, {"title": "Conjugate Acid-Base Pairs .txt", "text": "So, for example, let's look at the reaction of acetic acid and water."}, {"title": "Conjugate Acid-Base Pairs .txt", "text": "So in this case, our bronze and Lyley acid is our acetic acid and our bronchylori base is our water."}, {"title": "Conjugate Acid-Base Pairs .txt", "text": "And that's because this guy has an extra H ion."}, {"title": "Conjugate Acid-Base Pairs .txt", "text": "It donates that H plus ion."}, {"title": "Conjugate Acid-Base Pairs .txt", "text": "And this guy has a lone pair of electrons on its oxygen."}, {"title": "Conjugate Acid-Base Pairs .txt", "text": "And it has the potential to gain a proton."}, {"title": "Conjugate Acid-Base Pairs .txt", "text": "So this is our brocholyari base."}, {"title": "Conjugate Acid-Base Pairs .txt", "text": "Now, when they react this guy, our CBIC acid loses NH ion, while this guy, our water, gains NH ion."}, {"title": "Conjugate Acid-Base Pairs .txt", "text": "And that means if we look at these guys, this becomes our new base, our new bronze of Larry base."}, {"title": "Conjugate Acid-Base Pairs .txt", "text": "Because it now has the potential to gain an H ion because it has that electron pair on the O atom."}, {"title": "Conjugate Acid-Base Pairs .txt", "text": "This guy now has an extra H ion."}, {"title": "Conjugate Acid-Base Pairs .txt", "text": "So it has the potential to donate one."}, {"title": "Conjugate Acid-Base Pairs .txt", "text": "So this guy becomes our bronchit Larry acid."}, {"title": "Conjugate Acid-Base Pairs .txt", "text": "So we see that this statement holds true whenever we have an acid that reacts with a base, a new base and a new acid are formed."}, {"title": "Conjugate Acid-Base Pairs .txt", "text": "So let's define conjugate acid base pairs."}, {"title": "Conjugate Acid-Base Pairs .txt", "text": "So a pair of molecules or ions related to each other by the loss or gain of a single H plus ion are called conjugate acid base pairs."}, {"title": "Conjugate Acid-Base Pairs .txt", "text": "So let's go back to our above system."}, {"title": "Conjugate Acid-Base Pairs .txt", "text": "So we have an acid loser than H ion becoming a base."}, {"title": "Conjugate Acid-Base Pairs .txt", "text": "So this acid and this base are the conjugate acid base pairs."}, {"title": "Conjugate Acid-Base Pairs .txt", "text": "Likewise, this base gains an H becomes a new acid."}, {"title": "Conjugate Acid-Base Pairs .txt", "text": "So this base and this acid are the conjugate acid base pairs."}, {"title": "Conjugate Acid-Base Pairs .txt", "text": "So whenever we have a bronched Larry acid reacting with a bronzedidlory base, we will always form a conjugate Bronxed Larry acid and a conjugate bronson Larry base."}, {"title": "Conjugate Acid-Base Pairs .txt", "text": "For example, let's look at another reaction in which an acid, a bronsolaric acid reacts with a base water."}, {"title": "Conjugate Acid-Base Pairs .txt", "text": "What will happen is this has the potential to gain an H. So it will give off the H.\nAnd the lone pair of electrons on the base will take that H forming our new conjugate acid plus our new conjugate base."}, {"title": "Conjugate Acid-Base Pairs .txt", "text": "So this acid and this base are conjugate acid base pairs."}, {"title": "Conjugate Acid-Base Pairs .txt", "text": "And this base and this acid are conjugate acid base pairs."}, {"title": "Conjugate Acid-Base Pairs .txt", "text": "So notice that one member of a conjugate acid base pair is always found on one side, while the second member of the conjugate base pair is always found on the other side of the equation."}, {"title": "Conjugate Acid-Base Pairs .txt", "text": "You'll never find both members on one side."}, {"title": "Conjugate Acid-Base Pairs .txt", "text": "For example, this guy and this guy are found on different sides."}, {"title": "Conjugate Acid-Base Pairs .txt", "text": "And this guy and this guy are found different sides, just like this acid and this new base are found on different sides."}, {"title": "Conjugate Acid-Base Pairs .txt", "text": "And this base and this acid are found on different sides, so this always holds true."}, {"title": "Conjugate Acid-Base Pairs .txt", "text": "So, for example, if someone asked you to find a conjugate base of some asset, you would simply take away an H from that asset, and that would be your conjugate base."}, {"title": "Conjugate Acid-Base Pairs .txt", "text": "Now, likewise, if somebody gave you a base and asked it to find the conjugate acid, you would simply find the conjugate asset by giving or adding an H to our system."}, {"title": "Conjugate Acid-Base Pairs .txt", "text": "So, for example, if someone said that our acid is this and you need to find the conjugate base without knowing what this side was, you simply subtract an H. Likewise, if somebody gave you this and said, this is our base, find the conjugate acid, you simply add an H, and you will get your conjugate acid."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "In this lecture, we're going to talk about four important periodic trends atomic radius, ionization energy, electronegativity, and electron affinity of atoms."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "Now, let's begin with atomic radius."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "So what is an atomic radius?"}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "Well, it's exactly what you think it is."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "If you think about atom as being a sphere, then our radius begins at the center of our nucleus and ends at the outermost electron shell."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "So, for this atom, our radius is the black line."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "So I want to ask the question what happens to our italic radius as we go from left to right across the period on our periodic table?"}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "For example, let's take the following period."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "Let's begin with lithium and go all the way up to four."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "What happens to our atomic radius?"}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "Well, we see that atomic radius decreases as we go from lithium to fluorine."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "Why is that?"}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "Well, it's because of two things."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "First, the number of protons or number of protons found in our nucleus increases as we go from lithium to fluorine."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "And second, the number of electrons found on our most electron shell also increases."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "And this means, according to Coulomb's law, the force also increases."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "In other words, the force with which the protons pull the outermost electrons increases."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "And this means that our effective nuclear charge on our atom increases."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "And if the force is stronger, so the protons are pulling our outermost electrons with a greater force, that means our radius will decrease."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "The difference between the center, the nucleus and the outermost electron will decrease as we go across the period."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "So that means our lithium will have the highest radius, the largest radius, and the smallest effective nuclear charge, while our fluoride will have the highest effective nuclear charge and the smallest atomic radius."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "So now let's talk about a group."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "What happens as we go from top of the group to the bottom of the group?"}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "So let's look at the following group."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "Let's begin with lithium and go to sodium, then potassium, and so on."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "Well, as we go down the group, our atomic radius tends to increase."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "And this is because with which atom we add a new energy shell."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "So let's look at the following two atoms."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "Let's look at lithium and let's look at sodium."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "Sodium is right below lithium on the same group on the periodic table."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "So notice that we have two energy levels, one S and two S for the lithium, while the sodium has not two, but three energy levels."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "One S, two F and three S.\nNow, this addition of the three S means that our atom will grow in size, will enlarge."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "Where this guy, the atomos guy, is the three F. Shell."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "So that means when we move one down to potassium, potassium will have a four S. So potassium will be even larger than sodium and definitely larger than lithium."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "And that's exactly what we see."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "In other words, as we go down a group, our atomic radius tends to grow in size, while as we go across the period, our atomic radius tends to decrease because our effective nuclear charge of our atom tends to increase."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "So that's atomic radius."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "Now let's look at the ionization energy of our atoms."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "So what is ionization energy?"}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "Well, electrons don't simply come off the atoms by themselves."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "Remember, electrons are held together by electrostatic force that comes from the positively charged nucleus and the negatively charged electrons."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "So something must pull those electrons away."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "In other words, work or energy must be inputted into our system to pull that electron off."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "So therefore, we can define our ionization energy to be the energy required to pull off that electron."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "That outermost electron."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "Now more than one electron can be pulled off."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "For example, calcium."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "Calcium in its neutral state, can take away two electrons to become calcium plus two."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "So that means some atoms can pull away or can give off more than one electron."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "Now, the energy required to pull away that first electron is known as The First ionization energy, while the energy Required to pull away that second electron is Known as A second ionization energy and So on."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "Now let's look at the following now, the less likely an atom gives up the electron, the more energy is required to pull that electron off."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "And we see that as we go across a period, our ionization energy of our atom tends to increase."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "And to explain that, let's look at Coulomb's Law."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "Now, Coulomb's law once again states that the force is equal to a constant k times charge q one times charge q two divided by the distance between them squared, where this guy is a charge due to the nucleus and q two is the charge due to the electrons."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "Now what happens as we move, for example, from lithium to fluorine?"}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "We already said that our effective nuclear charge tends to increase as we go from left to right."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "So fluorine has the highest force."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "In other words, the protons found in the nucleus."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "Pull those electrons on the outermost electron shell with a lot of force, much more force than lithium or beryllium or boron or carbon."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "And that means it's going to require much more energy to pull those outermost electrons off."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "And that's exactly why as we go across the period from lithium to fluorine, our ionization energy tends to increase."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "Because as we go this way, we have a higher effective nuclear charge, which means we have a greater force."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "And also take this into account."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "As we go across, our atomic radius decreases, and that means our denominator."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "Our R also increases."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "So we see that our cues increase, our Rs decrease."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "And whenever the denominator decreases, that means our force tends to increase."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "So not only does this increase in charge cause the force to go up, but also the decrease in the r of the atomic radius tends to increase our force."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "So therefore, as we go from left to right, our ionization energy also increases."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "How Bad?"}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "When we go down a group."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "Well, when we go down the group, our atomic radius increases."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "And that means if we go back to Coulomb's Law, if our atomic radius increases, that means the difference between Q one and Q two or the protons and electrons increases."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "So our R also increases."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "And if there are increases, our denominators increase."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "And that means our force is less."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "So as we go down a group, our ionization energy tends to decrease."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "So to wrap up, basically, the higher your ionization energy is, the less likely you are to give up electrons."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "And we'll see that this directly translates into something called electronegativity."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "So let's look at the third periodic trend called electronegativity."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "Now, electronegativity is simply the ability of atoms to accept or attract other electrons."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "And we see that as we go from left to right, across the period, from Lithium to Fluorine, our Electronegativity increases."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "So let's examine why."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "Let's look at atomic structure and the electron configuration of lithium and compare to that of fluorine."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "Now, lithium has three electrons and three protons."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "So its nucleus is composed of only three protons, while its inner shell is composed of two electrons, and its outer shell is composed only of a single electron."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "Now let's look at the fluorine."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "Fluorine has nine protons in its nucleus."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "While two electrons are found in the inner shell, seven electrons are found on the outer shell."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "And that means because we have a higher nuclear or effective nuclear charge, we have a higher force."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "In other words, because we have nine protons in our nucleus and seven electrons on our outer shell, our force with which our nucleus pulls those electrons is much greater than the force with which these three protons are pulling a single electron."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "And so that means if we place some arbitrary electron equidistant between these two atoms what?"}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "We see that this fluorine will pull this electron with much more force than this guy."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "And that means as we go from lithium to beryllium, to boron, to a carbon to nitrogen to oxygen, finally, to fluorine our electronegativity increases, and in fact, fluorine is the most electronegative atom and electronegativity is actually measured on a scale called the polling scale, and it's given a highest value of 4.0."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "Now, as we go across the period from left to right, we see that our electronegativity increases how about as we go from top to bottom?"}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "Well, as we go from top to bottom, our atomic radius increases."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "So our force with which our protons in the nucleus pull those electrons decreases."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "Because remember, force, according to Coulomb's law, is equal to K times q one times q two over r two."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "So our denominator increases, decreasing our force."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "And so, therefore, as we go from top to bottom, our electronegativity decreases."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "Now for noble gases."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "Electro."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "Negativity is undefined."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "And that's because in Noble gas structure, the electron configuration is perfect."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "And what noble gases can't accept any more electrons?"}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "Because notice that this twopie orbital can accept one more electron."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "And that's exactly why fluorine can accept one more electron."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "But the next atom, the noble gas after this guy can't accept any more electrons because it has a two p six electron configuration."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "So let's look at our final periodic trend called electron affinity."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "Now."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "Electron affinity is the amount of energy released when an atom gains an electron."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "Remember, the only way to take an electron away from the outer shell of an atom is to apply work, is to input energy."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "Because work must be done against the force of the protons in the nucleus attracting those electrons, those outer electrons."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "So that means the reverse must be the following whenever an electron or whenever an atom gains an electron energy must be released."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "And that's exactly what happens when Fluorine, for example, gains electrons."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "When fluorine goes from a neutral molecule, gains an electron to form an anion, it loses energy."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "The energy level of the outer shell is lower."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "And therefore this molecule, this anion is more stable than the neutral counterpart."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "So this reaction going this way is exothermic."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "Now."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "That means whenever we go from Lithium to Beryllium to Boron and so on, whenever we go from left to right, our electron activity increases."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "And that means this guy, this reaction is more exothermic for fluorine than for lithium."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "In other words, whenever our fluorine gains electrons, it becomes stable and it loses a lot of energy."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "On the contrary, whenever this guy gains electrons, the reaction for this guy is endothermic."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "Because this guy, the lithium in the neutral state is more stable than the anion than lithium minus one."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "And that's exactly what we mean by electron affinity."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "Now."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "Likewise, as we go from top to bottom on our group in group, on the period our electron affinity decreases."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "And that's because our atomic radius increases as we go from top to bottom."}, {"title": "Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt", "text": "So as we go from top to bottom, we go from exothermic reactions to endothermic reactions."}, {"title": "Oxidation-Reduction Reactions .txt", "text": "Reduction, oxidation reactions, or simply reduced reactions, are chemical reactions in which electrons are transferred from one atom to another."}, {"title": "Oxidation-Reduction Reactions .txt", "text": "This transfer of electron causes A change in oxidation state or the oxidation number of the atoms."}, {"title": "Oxidation-Reduction Reactions .txt", "text": "Now, the atom that gains the electrons becomes more negative and is said to be reduced."}, {"title": "Oxidation-Reduction Reactions .txt", "text": "The atom that loses the electrons is said to be more positive and is said to be oxidized."}, {"title": "Oxidation-Reduction Reactions .txt", "text": "So let's look at atoms A and B."}, {"title": "Oxidation-Reduction Reactions .txt", "text": "Suppose atom A loses an electron, while atom B gains that same electron."}, {"title": "Oxidation-Reduction Reactions .txt", "text": "That means our charge of A goes from A neutral charge to A plus one charge."}, {"title": "Oxidation-Reduction Reactions .txt", "text": "It loses an electron, while atom B gains an electron."}, {"title": "Oxidation-Reduction Reactions .txt", "text": "So Its charge goes from A neutral charge to a negative one charge."}, {"title": "Oxidation-Reduction Reactions .txt", "text": "So species A or atom A is said to be oxidized, while atom B is set to be reduced."}, {"title": "Oxidation-Reduction Reactions .txt", "text": "Now, we can also look at it another way."}, {"title": "Oxidation-Reduction Reactions .txt", "text": "Atom A is a reducing agent."}, {"title": "Oxidation-Reduction Reactions .txt", "text": "Why?"}, {"title": "Oxidation-Reduction Reactions .txt", "text": "Well, because it reduces atom B."}, {"title": "Oxidation-Reduction Reactions .txt", "text": "It makes this atom more negative."}, {"title": "Oxidation-Reduction Reactions .txt", "text": "So we can also look at atom B as an oxidizing agent, because atom D takes away that electron from A, and it oxidizes A, and that's why it's the oxidizing agent."}, {"title": "Oxidation-Reduction Reactions .txt", "text": "So Oxidation, or the loss of electrons and reduction or the gain of electron always comes in a pair, the same way that acids are always paired with the base."}, {"title": "Oxidation-Reduction Reactions .txt", "text": "So let's look at the most common redox reaction out there two H, two molecules combined with a single O, two molecule forming two molecules of water."}, {"title": "Oxidation-Reduction Reactions .txt", "text": "So on this side, our H two is in its atomic state."}, {"title": "Oxidation-Reduction Reactions .txt", "text": "It's in its elemental state, and so is oxygen."}, {"title": "Oxidation-Reduction Reactions .txt", "text": "That means they both have A charge of zero."}, {"title": "Oxidation-Reduction Reactions .txt", "text": "Now, in this case, our oxygen becomes negative two, and our H becomes a positive two."}, {"title": "Oxidation-Reduction Reactions .txt", "text": "And two H's cause A positive two charge."}, {"title": "Oxidation-Reduction Reactions .txt", "text": "So our overall charge is zero."}, {"title": "Oxidation-Reduction Reactions .txt", "text": "But each atom gains or loses electrons."}, {"title": "Oxidation-Reduction Reactions .txt", "text": "So let's see what happens."}, {"title": "Oxidation-Reduction Reactions .txt", "text": "So, our H atom is the reducing agent, and it loses electrons, which means it's oxidized."}, {"title": "Oxidation-Reduction Reactions .txt", "text": "And that loss of electrons, those electrons are transferred to our oxygen molecule, and that means our oxygen molecule is reduced."}, {"title": "Oxidation-Reduction Reactions .txt", "text": "So this oxygen molecule is the oxidizing agent because it gains those electrons."}, {"title": "Oxidation-Reduction Reactions .txt", "text": "It takes those electrons away from that H molecule."}, {"title": "Order of Reactions .txt", "text": "So we already spoke about the order of reactions without actually mentioning what that is."}, {"title": "Order of Reactions .txt", "text": "So let's look at the following simple elementary irreversible reaction that only goes this direction."}, {"title": "Order of Reactions .txt", "text": "So our reactive x and the gas state reacts in a single step to produce two products, y and z, also in a gas state."}, {"title": "Order of Reactions .txt", "text": "Now, we already spoke about what the rate law was."}, {"title": "Order of Reactions .txt", "text": "The rate law of any reaction is a mathematical representation of the relationship between the concentration of the reactants and our rate of reaction."}, {"title": "Order of Reactions .txt", "text": "And we said that the general form is as follows rate of forward reaction is equal to the constant of our Ford reaction times the concentration of reactants to some power A."}, {"title": "Order of Reactions .txt", "text": "Now, this A represents the order of our reactants."}, {"title": "Order of Reactions .txt", "text": "And since the only reactant is the x reactant, this A represents the order of the entire reaction."}, {"title": "Order of Reactions .txt", "text": "Now, my question is how do we determine the order of our reaction, namely A and our rate constant KF?"}, {"title": "Order of Reactions .txt", "text": "Well, one way to do it, as we saw, is to determine using experimental results."}, {"title": "Order of Reactions .txt", "text": "So we find the initial concentrations and the initial rate and we use that information to determine their relationship or the relationship between A and our rate of our reaction."}, {"title": "Order of Reactions .txt", "text": "And using that this guy and our concentration, we can then find our KAP."}, {"title": "Order of Reactions .txt", "text": "Well, that's one way to do it."}, {"title": "Order of Reactions .txt", "text": "A second way to do it is with graphing."}, {"title": "Order of Reactions .txt", "text": "So we can graph concentration of reactants against time or progress of reaction."}, {"title": "Order of Reactions .txt", "text": "Now, there are three main graphs that we can get."}, {"title": "Order of Reactions .txt", "text": "Now let's look at the first one."}, {"title": "Order of Reactions .txt", "text": "The first one is known as the 0th order of our reaction."}, {"title": "Order of Reactions .txt", "text": "And that means our A is equal to zero."}, {"title": "Order of Reactions .txt", "text": "So this exponent A is zero and hence 0th order of our react."}, {"title": "Order of Reactions .txt", "text": "Now let's recall what the rate of reaction is."}, {"title": "Order of Reactions .txt", "text": "Well, the rate of any reaction or reactant is given by the following formula."}, {"title": "Order of Reactions .txt", "text": "Since we're going from reactants to products, our reactant concentration is decreasing, so the rate is negative."}, {"title": "Order of Reactions .txt", "text": "Change in x of concentration x divided by change in time is equal to our rate of forward."}, {"title": "Order of Reactions .txt", "text": "So k times our concentration of x."}, {"title": "Order of Reactions .txt", "text": "Now, since we're dealing with A equals zero, the zeros order, we plug in our zero for the exponent A."}, {"title": "Order of Reactions .txt", "text": "That means this guy, the x will go to zero."}, {"title": "Order of Reactions .txt", "text": "So let's rearrange this a bit."}, {"title": "Order of Reactions .txt", "text": "Let's bring the negative over here."}, {"title": "Order of Reactions .txt", "text": "Let's bring the T on this side and make this guy one because 80 power is one and we get change in concentration of x equals negative constant k times change in time."}, {"title": "Order of Reactions .txt", "text": "Now let's represent this guy and this guy following way."}, {"title": "Order of Reactions .txt", "text": "So the final concentration minus the initial concentration equals negative k in parentheses time final minus time initial."}, {"title": "Order of Reactions .txt", "text": "But what is time initial?"}, {"title": "Order of Reactions .txt", "text": "Time initial is time zero."}, {"title": "Order of Reactions .txt", "text": "So this guy is zero."}, {"title": "Order of Reactions .txt", "text": "So let's go here."}, {"title": "Order of Reactions .txt", "text": "Now, change in concentration of final minus change in concentration of initial gives you negative k times t final because this guy becomes zero."}, {"title": "Order of Reactions .txt", "text": "Now let's bring the initial over to this side and we get concentration of our final equals negative k times t final plus our initial concentration of x."}, {"title": "Order of Reactions .txt", "text": "And notice that this equation has the same form as y equals MX plus b."}, {"title": "Order of Reactions .txt", "text": "This is our general equation for a line."}, {"title": "Order of Reactions .txt", "text": "And that means if we plot this guy, we will get a line."}, {"title": "Order of Reactions .txt", "text": "So this is our y number, this is our Y intercept, this is our x value and this is our slope."}, {"title": "Order of Reactions .txt", "text": "Our slope is negative k. So if we plot this where our Y is the concentration of X and our X is the time or the progress of reaction, we get the following negative slope where this point is the .0\ncomma concentration of initial because it's time to zero, we plug in t zero and we get simply this guy equals this guy."}, {"title": "Order of Reactions .txt", "text": "That's exactly what this guy is."}, {"title": "Order of Reactions .txt", "text": "This is our initial concentration of our reactor."}, {"title": "Order of Reactions .txt", "text": "Now the slope represents negative k, this is our slope."}, {"title": "Order of Reactions .txt", "text": "So to find our slope, we simply find the final concentration, subtract that from initial concentration and divide it by the change in time, or M equals change in Y over change in X and we find our K value."}, {"title": "Order of Reactions .txt", "text": "And that's how we find our K.\nNow, in other words, to summarize, if after graphing our concentration of reactants versus time, we get a negative slope like this, we get a graph like this."}, {"title": "Order of Reactions .txt", "text": "That means our A must be one."}, {"title": "Order of Reactions .txt", "text": "So now let's look at what the graph would look like if our A was actually one, if our order was first order or A equals one."}, {"title": "Order of Reactions .txt", "text": "Now once again we begin the same way."}, {"title": "Order of Reactions .txt", "text": "Negative change in concentration of x over change in time is equal to our constant KDF times the concentration of x to the one power."}, {"title": "Order of Reactions .txt", "text": "So now this guy remains."}, {"title": "Order of Reactions .txt", "text": "So let's rearrange them a bit and we get well, we bring that change in concentration of x over this side and we bring our time or change in time to this side."}, {"title": "Order of Reactions .txt", "text": "We also bring the negative over to this side and we get change in concentration of x divided by concentration of x equals negative our constant times change in time."}, {"title": "Order of Reactions .txt", "text": "Now, in order to get from this guy to this guy, we have to use calculus and integrals."}, {"title": "Order of Reactions .txt", "text": "Now I will spare you the calculus and we'll simply jump to this step."}, {"title": "Order of Reactions .txt", "text": "If you're interested about what to do from this step to this step, leave a comment and I'll show you."}, {"title": "Order of Reactions .txt", "text": "So after we use calculus, we get natural log of the concentration of final minus natural log of concentration of initial equals negative k times time final minus time initial."}, {"title": "Order of Reactions .txt", "text": "Now this time initial is zero."}, {"title": "Order of Reactions .txt", "text": "So that becomes zero and we bring over this guy to the right side and we get natural log of the concentration final equals negative k times t final plus because this guy was brought over natural log of the concentration of an initial."}, {"title": "Order of Reactions .txt", "text": "Now, this guy also has the same form as the line as a line y equals MX plus B, where this guy is our Y value this guy."}, {"title": "Order of Reactions .txt", "text": "The b is our Y intercept."}, {"title": "Order of Reactions .txt", "text": "Our slope is negative k, and our x value is time."}, {"title": "Order of Reactions .txt", "text": "So let's graph this on an XY plane."}, {"title": "Order of Reactions .txt", "text": "So the y axis is our natural log of x of our concentration of reactive and our x axis is time or progress or reaction."}, {"title": "Order of Reactions .txt", "text": "And we see that once again our slope is negative k, our Y intercept is this guy."}, {"title": "Order of Reactions .txt", "text": "And in order to find our K, we simply use the slope."}, {"title": "Order of Reactions .txt", "text": "In other words, change in y over change in x."}, {"title": "Order of Reactions .txt", "text": "Now once again, if our A equals one, then when we graph this equation on the XY plane, we should get a negative slope like this a straight line."}, {"title": "Order of Reactions .txt", "text": "Now, suppose our A was zero, and we tried graphing this equation the same way."}, {"title": "Order of Reactions .txt", "text": "Then since A equals zero, this would not be a straight line, it'd be some other line."}, {"title": "Order of Reactions .txt", "text": "And that means we can conclude that our A is not one, our A must be something else."}, {"title": "Order of Reactions .txt", "text": "And in order to determine A equals zero, we have to actually graph what we graphed before and after we graph."}, {"title": "Order of Reactions .txt", "text": "If we got a straight negative line, we can conclude that our A equals zero."}, {"title": "Order of Reactions .txt", "text": "So finally, let's look at the graph for A equals two."}, {"title": "Order of Reactions .txt", "text": "So what will the graph look like when our exponent is two?"}, {"title": "Order of Reactions .txt", "text": "So this is called a second order reaction."}, {"title": "Order of Reactions .txt", "text": "And we begin the same way."}, {"title": "Order of Reactions .txt", "text": "Negative change in concentration of x divided by changes time."}, {"title": "Order of Reactions .txt", "text": "Our rate equal to this rate KF times the concentration is the second power because A equals two."}, {"title": "Order of Reactions .txt", "text": "Now, once again we rearrange."}, {"title": "Order of Reactions .txt", "text": "We get the following."}, {"title": "Order of Reactions .txt", "text": "Then we use calculus and simple algebra to find the following final equation."}, {"title": "Order of Reactions .txt", "text": "Now once again, if you're curious about this step, leave a comment and I'll show you."}, {"title": "Order of Reactions .txt", "text": "Now this equation also looks like a line."}, {"title": "Order of Reactions .txt", "text": "So y equals MX plus B, where our Y is this guy."}, {"title": "Order of Reactions .txt", "text": "Our slope is a k, our X is time, and our Y intercept is this guy."}, {"title": "Order of Reactions .txt", "text": "So we're going to get a straight line, positive straight line with a positive slope."}, {"title": "Order of Reactions .txt", "text": "And our intercept is this guy."}, {"title": "Order of Reactions .txt", "text": "And now our Y is this guy."}, {"title": "Order of Reactions .txt", "text": "One over change in concentration."}, {"title": "Order of Reactions .txt", "text": "So if our A is in fact two, we graph and plot this guy."}, {"title": "Order of Reactions .txt", "text": "We should get the following straight line positive line."}, {"title": "Order of Reactions .txt", "text": "And we can find the k by simply using the formula m equals change in y divided by change in x, where M is our slope and m is our."}, {"title": "Reaction Quotient .txt", "text": "So far we have spoken about the equilibrium constant of our reactions."}, {"title": "Reaction Quotient .txt", "text": "And we said that the equilibrium constant k allows us to see how far our reaction proceeded at equilibrium."}, {"title": "Reaction Quotient .txt", "text": "In other words, it only gives us information about our reaction at equilibrium when equilibrium is established."}, {"title": "Reaction Quotient .txt", "text": "Now, it would be nice is if we could somehow know more information about our reaction or about the progress of our reaction before equilibrium is actually established."}, {"title": "Reaction Quotient .txt", "text": "And this is exactly what the reaction quotient does."}, {"title": "Reaction Quotient .txt", "text": "It provides us more information about our reaction before equilibrium is established."}, {"title": "Reaction Quotient .txt", "text": "Now, the reaction quotient q is also just like the equilibrium constant k, the ratio of the concentration of products to the concentration of reactants."}, {"title": "Reaction Quotient .txt", "text": "But unlike our k, q does not refer to the equilibrium concentration."}, {"title": "Reaction Quotient .txt", "text": "Now, if we look at the following reaction, that is not an equilibrium in which x moles of A react with y moles of B to form our products c and d, both having z and w moles respectively."}, {"title": "Reaction Quotient .txt", "text": "Now our quotient, our reaction quotient is the same thing as our equilibrium constant in the sense that it's a ratio."}, {"title": "Reaction Quotient .txt", "text": "It's the ratio of this guy times the ratio."}, {"title": "Reaction Quotient .txt", "text": "It's the concentration of this guy times the concentration of this guy divided by the concentration of A times the concentration of B."}, {"title": "Reaction Quotient .txt", "text": "Now, these exponents come from the coefficients X-Y-Z and W. Now, if our q is equal to our k, that means our reaction is already at equilibrium."}, {"title": "Reaction Quotient .txt", "text": "Now, if q is greater than k at the beginning of our reaction, that means our reaction is reacting favorite."}, {"title": "Reaction Quotient .txt", "text": "And that's because let's look at the ratio."}, {"title": "Reaction Quotient .txt", "text": "If q is greater than k, that means the concentrations of our product c and d is greater than that in equilibrium."}, {"title": "Reaction Quotient .txt", "text": "And that means our equilibrium will shift this way."}, {"title": "Reaction Quotient .txt", "text": "In other words, these products will tend to convert to reactants."}, {"title": "Reaction Quotient .txt", "text": "And so our reaction is reactant favorite, meaning it's favored."}, {"title": "Reaction Quotient .txt", "text": "This way our reverse reaction is favored over our four reactions."}, {"title": "Reaction Quotient .txt", "text": "Now, if k is if q is less than k, that means our reaction is products favored."}, {"title": "Reaction Quotient .txt", "text": "So let's go back to the ratio."}, {"title": "Reaction Quotient .txt", "text": "So q being less than k means that our concentration of and d, our product is less than data equilibrium."}, {"title": "Reaction Quotient .txt", "text": "And what that means is A and B will tend to react to produce the C and D that is seen at equilibrium."}, {"title": "Reaction Quotient .txt", "text": "And therefore our forward reaction will be preferred over the reverse reaction."}, {"title": "Reaction Quotient .txt", "text": "And so this is called product favorite reactions or spontaneous reactions."}, {"title": "Concentration Cells .txt", "text": "The electrochemical cells that we have discussed so far have different reactions proceeding in an ammo in a cathode."}, {"title": "Concentration Cells .txt", "text": "And this difference in reactions creates something called electric potential, also known as a cell voltage."}, {"title": "Concentration Cells .txt", "text": "And we saw that understanding conditions of 1 bar pressure and one molar concentration, we can find find our cell voltage by using this formula where we first find our cell voltage of the anode and then subtract that from the capital."}, {"title": "Concentration Cells .txt", "text": "And these values can be looked up on a reduction half reaction table."}, {"title": "Concentration Cells .txt", "text": "Now, what happens when our conditions are not standard?"}, {"title": "Concentration Cells .txt", "text": "Well, then we have to use this formula."}, {"title": "Concentration Cells .txt", "text": "And we saw that this formula is called Nurse Formula."}, {"title": "Concentration Cells .txt", "text": "And what it basically tells us is that the concentration of our solutions in beaker One and Baker Two will make a difference."}, {"title": "Concentration Cells .txt", "text": "They will influence the final cell voltage of our cell."}, {"title": "Concentration Cells .txt", "text": "So, as of now, we've only really spoken about these types of electrochemical cells in which beaker One contains the oxidation reaction of some metal x."}, {"title": "Concentration Cells .txt", "text": "And Baker Two, the half cell two contains the reduction reaction in which some other metal, metal y, is reduced."}, {"title": "Concentration Cells .txt", "text": "So let's see what the overall net reduction reaction is."}, {"title": "Concentration Cells .txt", "text": "Well, our x metal releases an electron and also releases an x plus ion to our solution, increases the concentration of the x plus ion in Baker One."}, {"title": "Concentration Cells .txt", "text": "This electron then travels via the conductor into this second electrode, a different metal."}, {"title": "Concentration Cells .txt", "text": "Now, inside this electrode, this electron reacts with this y plus ion that is taken up into the electrode and they react to form our Y solid."}, {"title": "Concentration Cells .txt", "text": "Now, notice one type of reaction occurred that deals with X in this beaker."}, {"title": "Concentration Cells .txt", "text": "And a second type of reaction, a different reaction occurred in beaker Two."}, {"title": "Concentration Cells .txt", "text": "And this difference created something called a cell voltage."}, {"title": "Concentration Cells .txt", "text": "And we saw that once again, on the standing conditions, we use this formula, and on the nonstanding conditions, we use this formula."}, {"title": "Concentration Cells .txt", "text": "Now, I want to talk about a different type of electrochemical cell called the concentration cell."}, {"title": "Concentration Cells .txt", "text": "Now, in this cell, we also have two half cells or two beakers."}, {"title": "Concentration Cells .txt", "text": "We also have a salt bridge and a conductor with a bolt meter."}, {"title": "Concentration Cells .txt", "text": "The only difference is that now we have the same exact electrode."}, {"title": "Concentration Cells .txt", "text": "So this electrode might be composed of some metal x, and this electrode is also composed of that same metal."}, {"title": "Concentration Cells .txt", "text": "So now we have the same type of reaction occurring in Baker One and Baker Two."}, {"title": "Concentration Cells .txt", "text": "The only difference is we have different concentrations of solutions because we learned from this equation that even though this guy might be zero, the concentration difference will still create an electric potential or cell voltage."}, {"title": "Concentration Cells .txt", "text": "Now, what is this guy for, this type of electrochemical cell called the concentration cell?"}, {"title": "Concentration Cells .txt", "text": "Well, let's see."}, {"title": "Concentration Cells .txt", "text": "Well, our E of the cell or cell voltage of our cell is equal."}, {"title": "Concentration Cells .txt", "text": "To notice this guy is now zero, because if we try to find our E on the standard conditions what we will get is that this guy and this guy are actually the same."}, {"title": "Concentration Cells .txt", "text": "The value on our table is the same."}, {"title": "Concentration Cells .txt", "text": "So we subtract some number x minus x gives us zero so this guy goes to zero and what we are left with is this equation where now our cell voltage will depend strictly on the concentrations of our solutions."}, {"title": "Concentration Cells .txt", "text": "So let's look at an example of this reaction in order to really understand what a concentration cell is, let's create one."}, {"title": "Concentration Cells .txt", "text": "Suppose we have the following electrochemical setup we have two has cells in hassle number one, oxidation of solid copper takes place so this electrode is solid copper and our initial concentration of aqueous copper in beaker one is zero four five molar."}, {"title": "Concentration Cells .txt", "text": "Now in hassle number two, reduction of copper takes place and this copper or aqueous copper becomes copper solid."}, {"title": "Concentration Cells .txt", "text": "Now, this electrode is also copper solid but our concentration in beaker one is 0.5 molar so this guy is more concentrated and this guy is more dilute."}, {"title": "Concentration Cells .txt", "text": "So let's see what the net rethink reaction for this electrochemical cell is."}, {"title": "Concentration Cells .txt", "text": "So we add the oxidation reaction and the reduction reaction up and we get our net reactor to be the following notice that this copper solid and this copper solid cancel because they appear on both sides of the equation."}, {"title": "Concentration Cells .txt", "text": "Also the electrons cancel because they appear on both sides of the equation."}, {"title": "Concentration Cells .txt", "text": "What we are left with is this guy and this guy."}, {"title": "Concentration Cells .txt", "text": "Now, this guy actually comes from half cell number two, right?"}, {"title": "Concentration Cells .txt", "text": "Because when we ask these guys up, this guy from hazel number two will appear on the left side of our net equation while this aqueous copper will appear on the right side of our equation."}, {"title": "Concentration Cells .txt", "text": "So we go from a higher concentration from zero five to a lower concentration zero five and that makes sense."}, {"title": "Concentration Cells .txt", "text": "So if we were to write the equilibrium constant expression it would be this concentration divided by this concentration and we'll see why that's important in a second."}, {"title": "Concentration Cells .txt", "text": "1st, let's review exactly what happens in this setup."}, {"title": "Concentration Cells .txt", "text": "Well, this is the more dilute solution."}, {"title": "Concentration Cells .txt", "text": "Initially, we have very little aqueous cu two plus ions dissolved in our solution but as that reaction continues, this metal bar releases more of the copper ions into solution increasing the solution, making more concentrated."}, {"title": "Concentration Cells .txt", "text": "Likewise, this acreage copper is taken up by the metal bar because when electrons travel from this electrode to this electrode they react to form copper solid so this becomes more diluted or less concentrated."}, {"title": "Concentration Cells .txt", "text": "Eventually, when the two concentrations equal our reaction will stop because our cell voltage will be zero."}, {"title": "Concentration Cells .txt", "text": "So let's calculate our cell voltage and our initial condition of this concentration and this concentration."}, {"title": "Concentration Cells .txt", "text": "So our formula is this one but notice that this guy is zero because if we were to look up the values for this oxidation reaction and this reduction reaction we see that the magnitude is the same but signs are different so if we add these guys up, we will get zero."}, {"title": "Concentration Cells .txt", "text": "That's why this guy is zero."}, {"title": "Concentration Cells .txt", "text": "So our E is simply this whole guy here."}, {"title": "Concentration Cells .txt", "text": "Notice this is for 25 degrees Celsius."}, {"title": "Concentration Cells .txt", "text": "Now, why do we say log 0.5 over 0.5?"}, {"title": "Concentration Cells .txt", "text": "Well, remember, Q is like the equilibrium constant, except it's not an equilibrium."}, {"title": "Concentration Cells .txt", "text": "It's also the concentration of products over reactants."}, {"title": "Concentration Cells .txt", "text": "And in our net, we do reaction."}, {"title": "Concentration Cells .txt", "text": "The product is this guy in half cell number one, the concentration of 0.5005."}, {"title": "Concentration Cells .txt", "text": "And this is half cell number two, the reactant, which is found in this half cell number two."}, {"title": "Concentration Cells .txt", "text": "So our concentration is zero five."}, {"title": "Concentration Cells .txt", "text": "And that's why we divide 0.05 by 0.5."}, {"title": "Concentration Cells .txt", "text": "Now, our N number of moles of electrons is two moles, right?"}, {"title": "Concentration Cells .txt", "text": "Two moles up here on this side and two moles up here on this side."}, {"title": "Concentration Cells .txt", "text": "So our N is two."}, {"title": "Concentration Cells .txt", "text": "So we take our calculator, we plug it in, we get a negative number."}, {"title": "Concentration Cells .txt", "text": "But since we have a negative on the outside, that means our E, or cell voltage of our cell, is positive."}, {"title": "Concentration Cells .txt", "text": "So we see that even though the same exact reaction takes place here as it does here, a concentration or a different concentration in here and here results in a cell voltage."}, {"title": "Concentration Cells .txt", "text": "Now, of course, when the concentrations equal out, this will go to zero because log of one is zero."}, {"title": "Boiling and Melting Points of Alkanes .txt", "text": "Now, with this lecture, I need to talk about a few trends that exist in alkane compounds."}, {"title": "Boiling and Melting Points of Alkanes .txt", "text": "Now, we're going to specifically focus on melting point and boiling point."}, {"title": "Boiling and Melting Points of Alkanes .txt", "text": "Now, before we get to the trends, let's define intramolecular bonds and intermolecular bonds."}, {"title": "Boiling and Melting Points of Alkanes .txt", "text": "Now, intramolecular bonds are the bonds between the individual joe atoms within a given compound."}, {"title": "Boiling and Melting Points of Alkanes .txt", "text": "The intermolecular bonds are the bonds between different compounds."}, {"title": "Boiling and Melting Points of Alkanes .txt", "text": "Now, here we have two alkanes."}, {"title": "Boiling and Melting Points of Alkanes .txt", "text": "We have neopentane and pentane."}, {"title": "Boiling and Melting Points of Alkanes .txt", "text": "The intramlecular bonds within neopentane are the carbon carbon Covalent bonds and carbon H Covalent bonds."}, {"title": "Boiling and Melting Points of Alkanes .txt", "text": "Likewise, the intramolecular bonds in pentane are the carbon carbon Covalent bonds and the carbon H Covalent bonds, which aren't shown."}, {"title": "Boiling and Melting Points of Alkanes .txt", "text": "So for both types of alkanes and in fact, for all alkanes, the intramlecular bonds are Covalent bonds."}, {"title": "Boiling and Melting Points of Alkanes .txt", "text": "What about the intermolecular bonds?"}, {"title": "Boiling and Melting Points of Alkanes .txt", "text": "Well, if we just examine this molecule by itself, if we simply have one molecule or one compound, that means we have no intermolecular bonds."}, {"title": "Boiling and Melting Points of Alkanes .txt", "text": "Because in order to have an inter molecular bond, you have to have a second compound next to that compound."}, {"title": "Boiling and Melting Points of Alkanes .txt", "text": "So if this is all by itself, we have no intermolecular bonds."}, {"title": "Boiling and Melting Points of Alkanes .txt", "text": "If we place this pentane or some other alkane next to our neopentane, these two compounds will attract one another via intermolecular bonds."}, {"title": "Boiling and Melting Points of Alkanes .txt", "text": "And in this case, in the case of alkanes, we have Vanderbilt forces."}, {"title": "Boiling and Melting Points of Alkanes .txt", "text": "So the intermolecular bonds of alkanes are Vanderbilt forces."}, {"title": "Boiling and Melting Points of Alkanes .txt", "text": "And these are simply instantaneous dipoles created between the protons found in the nuclei and the electrons surrounding or orbiting those nuclei."}, {"title": "Boiling and Melting Points of Alkanes .txt", "text": "So these valuable forces exist only for a moment, and that's exactly why they are relatively weak forces compared to bonds like polar bonds."}, {"title": "Boiling and Melting Points of Alkanes .txt", "text": "Now, so let's talk about this blue region here."}, {"title": "Boiling and Melting Points of Alkanes .txt", "text": "So this blue region on pentane and neopentane represents the boundarbal forces, the instantaneous dipoles created by these two molecules."}, {"title": "Boiling and Melting Points of Alkanes .txt", "text": "Notice that this is relatively symmetrical."}, {"title": "Boiling and Melting Points of Alkanes .txt", "text": "It looks like a sphere, while this has an oval shape."}, {"title": "Boiling and Melting Points of Alkanes .txt", "text": "And this will become important when we'll talk about trends."}, {"title": "Boiling and Melting Points of Alkanes .txt", "text": "And we'll see why in just a second."}, {"title": "Boiling and Melting Points of Alkanes .txt", "text": "So the longer the carbon chain is, the higher the boiling point."}, {"title": "Boiling and Melting Points of Alkanes .txt", "text": "So why is that?"}, {"title": "Boiling and Melting Points of Alkanes .txt", "text": "So what that statement states is that this longer pentane molecule will have a higher boiling point than neopentane, which is shorter and more symmetrical."}, {"title": "Boiling and Melting Points of Alkanes .txt", "text": "Now let's define what a boiling point is."}, {"title": "Boiling and Melting Points of Alkanes .txt", "text": "The boiling point is the point at which our pentane goes from liquid or our meal pentane."}, {"title": "Boiling and Melting Points of Alkanes .txt", "text": "It goes from liquid to gas."}, {"title": "Boiling and Melting Points of Alkanes .txt", "text": "And that means whenever we go from liquid to gas, we're breaking intermolecular bonds."}, {"title": "Boiling and Melting Points of Alkanes .txt", "text": "So that means if this has a higher boiling point, that means this guy forms stronger intermolecular bonds."}, {"title": "Boiling and Melting Points of Alkanes .txt", "text": "And that's exactly why longer the longer our carbon chain is, the stronger our intermolecular bonds are, because we have more surface area, we have more vandalbile forces than in this symmetrical case."}, {"title": "Boiling and Melting Points of Alkanes .txt", "text": "Remember, whenever we have a sphere, we have the minimum amount of surface area."}, {"title": "Boiling and Melting Points of Alkanes .txt", "text": "So the longer our alkane is, the higher the boiling point is."}, {"title": "Boiling and Melting Points of Alkanes .txt", "text": "Now, on the contrary, the more symmetry we have in our alkane, the higher the melting point is."}, {"title": "Boiling and Melting Points of Alkanes .txt", "text": "Now, why is that?"}, {"title": "Boiling and Melting Points of Alkanes .txt", "text": "Well, in a solid, we have a lot of symmetry, right?"}, {"title": "Boiling and Melting Points of Alkanes .txt", "text": "We have a crystal lattice, and we have very well structured molecules."}, {"title": "Boiling and Melting Points of Alkanes .txt", "text": "So because this has more symmetry, it's more compact, it will be able to form a better solid."}, {"title": "Boiling and Melting Points of Alkanes .txt", "text": "And that means more energy needs to be inputted to break the solid and turn into liquid."}, {"title": "Boiling and Melting Points of Alkanes .txt", "text": "And that's exactly why this neopentane will have a higher melting point, because it's more symmetrical and it's able to come itself into a solid state much better than this pentane molecule."}, {"title": "Entropy and Third Law of Thermodynamics .txt", "text": "So when we talk about systems, we simply talk about objects or things of interest, things that we're studying."}, {"title": "Entropy and Third Law of Thermodynamics .txt", "text": "And everything outside of the system is called the surrounding."}, {"title": "Entropy and Third Law of Thermodynamics .txt", "text": "Now, when we talk about entropy, we represent entropy with the letter S and changes in entropy with delta S.\nSo according to the conservation of energy, delta S or the change in entropy of the system plus the change in entropy, the surrounding will give you the change in entropy of the universe."}, {"title": "Entropy and Third Law of Thermodynamics .txt", "text": "Okay?"}, {"title": "Entropy and Third Law of Thermodynamics .txt", "text": "Now remember, the Universe is an isolated system."}, {"title": "Entropy and Third Law of Thermodynamics .txt", "text": "And according to the second law of thermodynamics, an isolated system cannot decrease in entropy."}, {"title": "Entropy and Third Law of Thermodynamics .txt", "text": "That is, the entropy must either remain the same or it might increase."}, {"title": "Entropy and Third Law of Thermodynamics .txt", "text": "Okay?"}, {"title": "Entropy and Third Law of Thermodynamics .txt", "text": "So we could represent this formula in another way, basically the same thing, except now we have this zero here, greater than or equal to zero."}, {"title": "Entropy and Third Law of Thermodynamics .txt", "text": "So the total entropy of the universe can never decrease."}, {"title": "Entropy and Third Law of Thermodynamics .txt", "text": "It must either remain the same or it must increase."}, {"title": "Entropy and Third Law of Thermodynamics .txt", "text": "What this also says is that the entropy of the system can decrease as long as there is a greater or equal increase in the entropy of the surrounding."}, {"title": "Entropy and Third Law of Thermodynamics .txt", "text": "Suppose that this decreases by ten."}, {"title": "Entropy and Third Law of Thermodynamics .txt", "text": "So this is negative ten."}, {"title": "Entropy and Third Law of Thermodynamics .txt", "text": "If this is ten, there's an increase in the universe by ten."}, {"title": "Entropy and Third Law of Thermodynamics .txt", "text": "Then you get negative ten plus ten will give you zero."}, {"title": "Entropy and Third Law of Thermodynamics .txt", "text": "So that works."}, {"title": "Entropy and Third Law of Thermodynamics .txt", "text": "If this decreases by negative ten and this increases by, say, eleven, then negative ten plus eleven will give you one also positive."}, {"title": "Entropy and Third Law of Thermodynamics .txt", "text": "So that works."}, {"title": "Entropy and Third Law of Thermodynamics .txt", "text": "But if we get negative ten, so the system decreases in entropy by negative ten, but the universe increases only by nine, then we get negative ten plus nine will give you negative one, a negative number, a violation of the second law of thermodynamics."}, {"title": "Entropy and Third Law of Thermodynamics .txt", "text": "And this basically tells us that if the entropy of the system decreases, then the entropy of the surroundings must increase by the same amount or greater."}, {"title": "Entropy and Third Law of Thermodynamics .txt", "text": "You can never increase by less."}, {"title": "Entropy and Third Law of Thermodynamics .txt", "text": "Okay, now let's look at these isolated systems."}, {"title": "Entropy and Third Law of Thermodynamics .txt", "text": "We're going to define entropy in a different way."}, {"title": "Entropy and Third Law of Thermodynamics .txt", "text": "Now, a third way."}, {"title": "Entropy and Third Law of Thermodynamics .txt", "text": "Now, in this system, we have six molecules on this side and two molecules on this side."}, {"title": "Entropy and Third Law of Thermodynamics .txt", "text": "Okay?"}, {"title": "Entropy and Third Law of Thermodynamics .txt", "text": "So we have more molecules here than here."}, {"title": "Entropy and Third Law of Thermodynamics .txt", "text": "So according to the probability theory of entropy, or the probability definition of entropy, what will happen?"}, {"title": "Entropy and Third Law of Thermodynamics .txt", "text": "Well, two of these will want to go into here."}, {"title": "Entropy and Third Law of Thermodynamics .txt", "text": "That situation will be more probable."}, {"title": "Entropy and Third Law of Thermodynamics .txt", "text": "So we want to even out."}, {"title": "Entropy and Third Law of Thermodynamics .txt", "text": "We want our system to be even."}, {"title": "Entropy and Third Law of Thermodynamics .txt", "text": "We want four molecules here and four molecules here."}, {"title": "Entropy and Third Law of Thermodynamics .txt", "text": "Okay?"}, {"title": "Entropy and Third Law of Thermodynamics .txt", "text": "So according to the probability definition of entropy, this is more likely, more probable."}, {"title": "Entropy and Third Law of Thermodynamics .txt", "text": "So another way to define entropy would be as follows."}, {"title": "Entropy and Third Law of Thermodynamics .txt", "text": "Entropy is nature's way to spread energy evenly throughout a system."}, {"title": "Entropy and Third Law of Thermodynamics .txt", "text": "So if you have a reaction where the reactants have much more molecules than the product, then the equation or the reaction will tend to go right because there are less molecules on the product."}, {"title": "Entropy and Third Law of Thermodynamics .txt", "text": "Side than the reactive side."}, {"title": "Entropy and Third Law of Thermodynamics .txt", "text": "The last thing that we should talk about when we talk about entropy is the third law of thermodynamics."}, {"title": "Entropy and Third Law of Thermodynamics .txt", "text": "But before we get into that, let's define entropy mathematically using a formula."}, {"title": "Entropy and Third Law of Thermodynamics .txt", "text": "The formula for Entropy is as follows."}, {"title": "Entropy and Third Law of Thermodynamics .txt", "text": "Change in entropy is equal to change in heat over temperature."}, {"title": "Entropy and Third Law of Thermodynamics .txt", "text": "And it has the units joules per kelvin."}, {"title": "Entropy and Third Law of Thermodynamics .txt", "text": "Now, what the third law does is it assigns a zero entropy value to all elements that are at zero kelvin."}, {"title": "Entropy and Third Law of Thermodynamics .txt", "text": "But remember, kelvin or zero Kelvin is attainable."}, {"title": "Entropy and Third Law of Thermodynamics .txt", "text": "And let's t y well, this formula says that the temperature, in fact, was zero."}, {"title": "Entropy and Third Law of Thermodynamics .txt", "text": "The zero here would be a denominator."}, {"title": "Entropy and Third Law of Thermodynamics .txt", "text": "And that's impossible mathematically, because anything over zero is undefined."}, {"title": "Entropy and Third Law of Thermodynamics .txt", "text": "Okay, now, last two things that we should mention is that entropy is an extensive property."}, {"title": "Entropy and Third Law of Thermodynamics .txt", "text": "And what that basically means that if the system grows in size, entropy increases."}, {"title": "Entropy and Third Law of Thermodynamics .txt", "text": "So if the system grows in volume, the entropy increases because there is more room for the molecules to move around."}, {"title": "Entropy and Third Law of Thermodynamics .txt", "text": "If temperature increases, the kinetic energy of the molecules increase."}, {"title": "Entropy and Third Law of Thermodynamics .txt", "text": "The molecules move around more violently, quicker and faster, until the entropy increases."}, {"title": "Entropy and Third Law of Thermodynamics .txt", "text": "If the number of moles increases, the number of particles increases."}, {"title": "Entropy and Third Law of Thermodynamics .txt", "text": "There are more particles, so the entropy increases as well."}, {"title": "Entropy and Third Law of Thermodynamics .txt", "text": "The last thing we should mention is that entropy is a state function."}, {"title": "Entropy and Third Law of Thermodynamics .txt", "text": "And what that basically means is that change in entropy of the forward reaction is equal to the negative of that reverse reaction."}, {"title": "Entropy and Third Law of Thermodynamics .txt", "text": "And what that means is as follows."}, {"title": "Entropy and Third Law of Thermodynamics .txt", "text": "If we look at the reaction here, a plus B forms C, we go from two molecules to one molecule."}, {"title": "Entropy and Third Law of Thermodynamics .txt", "text": "So entropy decreases."}, {"title": "Entropy and Third Law of Thermodynamics .txt", "text": "The reverse reaction would mean that we go from C to A plus B."}, {"title": "Entropy and Third Law of Thermodynamics .txt", "text": "So we go from C one molecule to two molecules."}, {"title": "Entropy and Third Law of Thermodynamics .txt", "text": "So, according to this, because entropy is a state function, the reverse reaction is the negative."}, {"title": "Entropy and Third Law of Thermodynamics .txt", "text": "The Ford reaction."}, {"title": "Entropy and Third Law of Thermodynamics .txt", "text": "So negative times negative 1010 or negative 110?"}, {"title": "Entropy and Third Law of Thermodynamics .txt", "text": "Negative."}, {"title": "Entropy and Third Law of Thermodynamics .txt", "text": "Ten is positive ten?"}, {"title": "Vapor pressure.txt", "text": "Whenever we talk about vapor pressure, we talk about a closed system."}, {"title": "Vapor pressure.txt", "text": "A closed system is a system in which no mass leaves the system."}, {"title": "Vapor pressure.txt", "text": "So no molecules leave the system."}, {"title": "Vapor pressure.txt", "text": "Now, we also talk about two phases being present in the system either liquid and gas or solid in gas."}, {"title": "Vapor pressure.txt", "text": "Now imagine we had a closed container."}, {"title": "Vapor pressure.txt", "text": "In this container."}, {"title": "Vapor pressure.txt", "text": "We had a batch vacuum, and we could somehow inject a liquid into this vacuum."}, {"title": "Vapor pressure.txt", "text": "So we have empty space and we have the liquid on the bottom."}, {"title": "Vapor pressure.txt", "text": "Now, any of these molecules at any given time has some kinetic energy."}, {"title": "Vapor pressure.txt", "text": "Now, if the kinetic energy is high enough, they could escape the liquid phase and become a gas molecule."}, {"title": "Vapor pressure.txt", "text": "And this is called evaporation."}, {"title": "Vapor pressure.txt", "text": "Condensation is the opposite."}, {"title": "Vapor pressure.txt", "text": "It's the process by which gas molecules hitting the surface of the liquid get stuck in the liquid."}, {"title": "Vapor pressure.txt", "text": "Now, when the rates of evaporation equal condensation, the state is an equilibrium."}, {"title": "Vapor pressure.txt", "text": "And when the state is in the equilibrium, we can measure the pressure exerted by the gas molecules on the wall of the container."}, {"title": "Vapor pressure.txt", "text": "And this pressure is called vapor pressure."}, {"title": "Vapor pressure.txt", "text": "So vapor pressure, by definition, is the pressure exerted by gas molecules that are in equilibrium with their liquid or solid state."}, {"title": "Vapor pressure.txt", "text": "And at this point, the rate of molecules leaving the solid or liquid state is equal to the rate at which they enter that state."}, {"title": "Vapor pressure.txt", "text": "Now, from everyday experience, we know a hot liquid will evaporate quicker than a cold liquid."}, {"title": "Vapor pressure.txt", "text": "And this is because vapor pressure is related to kinetic energy and temperature."}, {"title": "Vapor pressure.txt", "text": "This equation shows exactly that."}, {"title": "Vapor pressure.txt", "text": "This equation shows that if we increase temperature, we will increase the partial pressure."}, {"title": "Vapor pressure.txt", "text": "And that means we have more kinetic energy."}, {"title": "Vapor pressure.txt", "text": "The more kinetic energy we have, the more molecules we have that will leave the liquid state and travel into the gas state."}, {"title": "Vapor pressure.txt", "text": "Volatility is the ability of molecules to evaporate."}, {"title": "Vapor pressure.txt", "text": "So a volatile substance will evaporate quickly."}, {"title": "Vapor pressure.txt", "text": "An example of one is alcohol."}, {"title": "Vapor pressure.txt", "text": "Nonvolatile substances are those molecules that will not evaporate quickly."}, {"title": "Vapor pressure.txt", "text": "Boiling point is the temperature at which the vapor pressure of the liquid equals atmospheric pressure."}, {"title": "Vapor pressure.txt", "text": "At this point, more liquid molecules have a higher kinetic energy and therefore more likely to escape into the gas state."}, {"title": "Vapor pressure.txt", "text": "Melting point is the temperature at which the vapor pressure of the liquid equals the vapor pressure of the solid."}, {"title": "Vapor pressure.txt", "text": "At this point, more solid molecules have more kinetic energy and therefore are more likely to escape into the liquid state."}, {"title": "Vapor pressure.txt", "text": "Intermolecular bonds are those bonds?"}, {"title": "Vapor pressure.txt", "text": "Noncovalent bonds that hold molecules together in the liquid and solid states."}, {"title": "Vapor pressure.txt", "text": "Stronger."}, {"title": "Vapor pressure.txt", "text": "Tim."}, {"title": "Vapor pressure.txt", "text": "Molecular bonds will require more energy and a higher temperature to break."}, {"title": "Vapor pressure.txt", "text": "That means the boiling point will increase."}, {"title": "Vapor pressure.txt", "text": "That's why Alcohol, which Has Very Weaker Tummolcular Bonds, will Boil At A Lower Temperature."}, {"title": "Vapor pressure.txt", "text": "Richard, than, say, Water, which has Very strong Attempt, like lemons."}, {"title": "Factors that Affect Solubility.txt", "text": "So gases and solids can both dissolve in liquids and the way in which dissolved in liquid can be influenced by certain things, certain factors."}, {"title": "Factors that Affect Solubility.txt", "text": "For gases."}, {"title": "Factors that Affect Solubility.txt", "text": "I've outlined four different factors."}, {"title": "Factors that Affect Solubility.txt", "text": "The first thing that influences a gasolubility within a given liquid is something called Henry's Law."}, {"title": "Factors that Affect Solubility.txt", "text": "And Henry's law is a formula that relates to solubility of the gas, to the pressure of the gas."}, {"title": "Factors that Affect Solubility.txt", "text": "And the high the pressure, the higher the solubility."}, {"title": "Factors that Affect Solubility.txt", "text": "For example, suppose we have a soda can."}, {"title": "Factors that Affect Solubility.txt", "text": "Now."}, {"title": "Factors that Affect Solubility.txt", "text": "How are they able to get so much gas in the liquid in a soda can?"}, {"title": "Factors that Affect Solubility.txt", "text": "Well, that's because they decreased the volume to such a small volume found above the liquid that the increase in pressure Increase in pressure."}, {"title": "Factors that Affect Solubility.txt", "text": "Causes solubility of the gas to increase."}, {"title": "Factors that Affect Solubility.txt", "text": "And so a lot of the carbon dioxide found above the liquid in a soda can dissolves in the liquid."}, {"title": "Factors that Affect Solubility.txt", "text": "But when you open the liquid, the pressure decreases because there's an influx or an alflux of molecules out of the can."}, {"title": "Factors that Affect Solubility.txt", "text": "And therefore the alflux creates a lower pressure."}, {"title": "Factors that Affect Solubility.txt", "text": "A lower pressure means Solubility decreases."}, {"title": "Factors that Affect Solubility.txt", "text": "A lot of the molecules will leave the liquid and you will get a stale tasting soda."}, {"title": "Factors that Affect Solubility.txt", "text": "The second thing that influences solubility of gases is temperature."}, {"title": "Factors that Affect Solubility.txt", "text": "The higher the temperature, the less soluble something is."}, {"title": "Factors that Affect Solubility.txt", "text": "Or a gas is."}, {"title": "Factors that Affect Solubility.txt", "text": "And that's because it has more kinetic energy and will be less likely to stay within the liquid."}, {"title": "Factors that Affect Solubility.txt", "text": "Sites also influence the solubility."}, {"title": "Factors that Affect Solubility.txt", "text": "Larger molecules, experience larger vandal forces and tend to increase in solubility."}, {"title": "Factors that Affect Solubility.txt", "text": "And that's because a larger or heavier molecule will be pulled more strongly by the liquid and therefore will be more likely to dissolve within the liquid."}, {"title": "Factors that Affect Solubility.txt", "text": "Finally, gases that chemically react with liquids dissolve more readily in a liquid."}, {"title": "Factors that Affect Solubility.txt", "text": "Now for liquids and solids, it's a little different."}, {"title": "Factors that Affect Solubility.txt", "text": "Now."}, {"title": "Factors that Affect Solubility.txt", "text": "Liquids and solids are not compressible and therefore changes in pressure has no effect on Solubility."}, {"title": "Factors that Affect Solubility.txt", "text": "So there is no Henry's Law for liquids and solids."}, {"title": "Factors that Affect Solubility.txt", "text": "However, temperature now increases Solubility."}, {"title": "Factors that Affect Solubility.txt", "text": "For gases."}, {"title": "Factors that Affect Solubility.txt", "text": "We saw there is a decrease in Solubility when the temperatures increased."}, {"title": "Factors that Affect Solubility.txt", "text": "For liquids and solids."}, {"title": "Factors that Affect Solubility.txt", "text": "It's the opposite."}, {"title": "Factors that Affect Solubility.txt", "text": "And that's because, for example, when salts dissolve in a liquid, entropy increases."}, {"title": "Factors that Affect Solubility.txt", "text": "Entropy becomes positive."}, {"title": "Factors that Affect Solubility.txt", "text": "And so if we look at Git's free energy at higher temperatures, this component becomes positive."}, {"title": "Factors that Affect Solubility.txt", "text": "At higher temperatures."}, {"title": "Factors that Affect Solubility.txt", "text": "This guy will be negative."}, {"title": "Factors that Affect Solubility.txt", "text": "So this guy will be negative."}, {"title": "Factors that Affect Solubility.txt", "text": "Therefore the reaction will be more spontaneous."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "So in this lecture, we're going to continue drawing out louis dot structures."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "So let's begin."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "Here we have A-B-C and DME."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "So we have five examples."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "So let's begin."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "So, in part a, we want to draw the lewis structure for ch three."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "Now our first step is to figure out the amount or the number of balanced electrons in this molecule, in this ch three molecule."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "So let's begin by drawing out our carbon electron configuration."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "So we have two electrons that go into one s orbital, two electrons that go into the two s orbital, and two more electrons that go into our two p orbital."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "For h, we have only one electron, and that one electron goes into our one s orbital."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "Now, to count the number of balanced electrons, we simply have to figure out what the number of electrons are for carbon that are located in the outermost shell."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "The outermost shell is the n equals two shell."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "And in the N equals two shell, we have two plus two four electrons."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "So that means we have four bounce electrons for carbon for h, because we have only one electron, and this one electron is an outermost one s shell, we have one balance electron for each H atom."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "So four plus three, because we have three h atoms, and each h atom donates one balance electrons, we have a total of seven electrons."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "Now, notice that this guy is neutral, so this stays the same."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "If, for example, this had a negative one on top, that means we have one extra electron."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "So if there would be a negative one here, this would have been eight electrons."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "But since this is neutral, there's no charge on top."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "This stays at seven electrons."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "So let's begin drawing our lewiston structure."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "So we counted four balanced electrons for carbon."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "So we're going to have three bonding electrons for carbon and one non bonding."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "What that basically means is that three electrons that carbon will donate will be part of a bond, while one electron, which will be found here, won't be part of that bond."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "Now, each h atom will donate one electron each."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "So let's draw our one electron each."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "So these two electrons, where one came from h and one came for c, will be shared by these two atoms, and they will create a sigma bond, or also known as a covalent bond."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "And we can represent that by simply drawing this dashed line here."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "So here's our depiction, or our low style structure of ch three."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "Then let's make sure that this is, in fact, the correct picture."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "Once again, we have seven electrons."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "So 123-4567."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "This line represents two electrons."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "So this satisfies our condition."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "And this is, in fact, the correct drawing for the lewis dot structure for this guy."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "So let's go to part b."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "In part in part b, we have a ch two atom."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "So we have one less h atom as compared to part A."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "So once again, let's draw our electron configuration for both atoms, which is exactly the same as in part A, we have two electrons in the one s and four electrons in the balanced shell."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "So in the two s and the two p. Now we have two h atoms."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "So that means we're going to have one less electron than in part A."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "And notice that this is a neutral atom."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "So we're going to have four plus two electrons."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "So six electrons."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "So let's look at our depiction here."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "So once again we're going to get four electrons that come from the h atom from the C atom."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "And two of these electrons will be bonding electrons."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "That is, they will bond or be shared with two atoms, these two h atoms."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "And now we have two non bonding electrons left over."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "So let's put them in the bond up here."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "Now we have two electrons coming from h, so let's fill them in and let's draw our bond."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "So here we have two electrons coming from here and two electrons here and two electrons here."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "So two two and two gives us six."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "So this is in fact, a correct picture."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "Now this is once again a sigma bond, and this is our non bonding pair of electrons."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "So let's go to part C.\nIn part C we have NH three or ammonia."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "So in this case, we have an N atom."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "So let's throw out our electron configuration for N.\nSo two electrons go into the one s, two electrons going to the two s, and now we have three electrons going to our two p. So altogether we have five balanced electrons because we have five electrons in the outermost shell for anna."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "Now we have the same story as before."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "For h, we have one electron that goes into the one s. And because we have three h's, that the five plus three gives us eight electrons."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "So let's throw out our depiction here."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "So once again, anna will start with n will start with a central carbon central atom."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "So we have five electrons."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "So we're going to have three bonding electrons."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "So let's show them here."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "And then we're going to have two electrons left over."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "So let's put them in our orbital here, and let's also add our electrons that come from our h atom."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "So here we have this situation."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "So let's still in our line."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "So here we have the following lewis structure for ammonia."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "Now we have two electrons that are shared here, two electrons shared here, and two electrons shared here."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "So that's two plus two plus two, six plus two in the non bonding."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "So we have a total of eight electrons, and this is in fact, a neutral ammonia atom."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "So let's go to part D and part D. We basically have a combination of part A and an N atom."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "So once again, from part A and from part C, we have the following electron configuration for our HC and N atom."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "Respectfully now, a total of twelve electrons because we're going to have three electrons that come from our H. We have five electrons coming from our N, and we have four electrons coming from our carbon atom."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "So here's our depiction."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "So once again, let's begin with the central atom."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "Let's begin with our carbon."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "We're going to have four electrons coming for a carbon, and this time all of them will be part of a bond or they're going to be bonding electrons."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "Let's show our three electrons, one each from the H. And here we have like so let's fill in our lines."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "And now we're going to have five electrons coming from our N.\nSo one of these electrons will come from one of these electrons will be a bonding electron."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "The other two electrons will be part of the non bonding configuration."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "So they're going to be in the orbital and they won't be bonding."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "So let's fill this guy in."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "And here's our depiction."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "So as you would expect, N should have five electrons to have a neutral charge, c should have four electrons to have a neutral charge and H should have one each."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "And this is the same exact picture."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "So that means we have a neutral charge."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "And this is the same thing as this."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "So let's make sure we have twelve electrons."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "1234-5678, 910, eleven, one, two."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "So this satisfies our condition, our neutral condition."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "So we're done here."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "So let's go to part E. This is a more complicated example."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "We have the following atom or molecule."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "We have 123456 h atoms."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "That means we're going to have six bounds electrons altogether coming from the H atoms."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "And we have 1234."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "We have four carbon atoms."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "So each carbon atom donates four bounds electrons four times 416 plus 622 electrons altogether."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "So let's begin."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "So once again, we're going to have four electrons coming from our carbon atom."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "Okay?"}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "So we have one, two, and then we're going to have four more."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "Now remember an important point."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "Carbon is able to double bond."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "So in this case, we're going to have double bonds."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "So let's let's first draw out all our bounce electrons for carbon."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "So we have 1234 for this carbon."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "We're going to have one, two, three and four for this carbon."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "We're going to have one, two, three and four for this carbon."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "And we're going to have well, actually, let's put this guy here and then we're going to have 1234 for that carbon and let's finish our HS."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "So one each."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "So one, one and one."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "So now let's fill in our lines."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "So we have like so like so there you go."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "We have one here."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "We have one here, one here."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "We have two here, one here and one here."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "So we're going to have two double bonds here."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "One between these two carbons and one between these two carbons."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "So let's count and make sure this is in fact our balanced electron for this neutral atom that has neutral molecule that has 22 electrons."}, {"title": "Drawing Lewis Structures Example #1 .txt", "text": "So 1234-5678, 910, 1112, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22 so this is in fact our Lewis dot structure for this following neutral compound."}, {"title": "Methyl Cation, Methyl Anion, and Methyl Radical Intermediates .txt", "text": "In this lecture, I'd like to examine a few important reactive intermediates that can be produced from a methane molecule."}, {"title": "Methyl Cation, Methyl Anion, and Methyl Radical Intermediates .txt", "text": "Now, reactive intermediates are simply molecules or compounds that are too unstable and reactive to exist for a very long time."}, {"title": "Methyl Cation, Methyl Anion, and Methyl Radical Intermediates .txt", "text": "So they exist for a very short time, and they react with other compounds and molecules to produce new compounds."}, {"title": "Methyl Cation, Methyl Anion, and Methyl Radical Intermediates .txt", "text": "So let's look at the following methane molecule."}, {"title": "Methyl Cation, Methyl Anion, and Methyl Radical Intermediates .txt", "text": "So, in this react here, we have the following ch bond that dissociates."}, {"title": "Methyl Cation, Methyl Anion, and Methyl Radical Intermediates .txt", "text": "So this bond breaks in such a way that the two electrons go directly onto our H atom."}, {"title": "Methyl Cation, Methyl Anion, and Methyl Radical Intermediates .txt", "text": "So we get the following two reactive intermediates."}, {"title": "Methyl Cation, Methyl Anion, and Methyl Radical Intermediates .txt", "text": "We get the methylcat ion, and we get this Hydride ion."}, {"title": "Methyl Cation, Methyl Anion, and Methyl Radical Intermediates .txt", "text": "So this Hydride molecule has two electrons in the one S state, in the one S orbital."}, {"title": "Methyl Cation, Methyl Anion, and Methyl Radical Intermediates .txt", "text": "So it has a negative charge."}, {"title": "Methyl Cation, Methyl Anion, and Methyl Radical Intermediates .txt", "text": "This methylcat ion has a positive charge on the carbon."}, {"title": "Methyl Cation, Methyl Anion, and Methyl Radical Intermediates .txt", "text": "That means it has one less electron than it should in its neutral state."}, {"title": "Methyl Cation, Methyl Anion, and Methyl Radical Intermediates .txt", "text": "Now, this guy will be very active because it will tend to act as a lewis base donating that pair of electrons."}, {"title": "Methyl Cation, Methyl Anion, and Methyl Radical Intermediates .txt", "text": "Likewise, this guy will also be very active."}, {"title": "Methyl Cation, Methyl Anion, and Methyl Radical Intermediates .txt", "text": "It will tend to accept a pair of electrons into its empty orbital, which we'll see in just a second."}, {"title": "Methyl Cation, Methyl Anion, and Methyl Radical Intermediates .txt", "text": "So let's look at the second type of reaction."}, {"title": "Methyl Cation, Methyl Anion, and Methyl Radical Intermediates .txt", "text": "Now, this methane molecule, the ch bond, also dissociates, but now it associates in a way such that the pair of electrons go onto the carbon atoms."}, {"title": "Methyl Cation, Methyl Anion, and Methyl Radical Intermediates .txt", "text": "So now we get a methyl anion and a positively charged H atom."}, {"title": "Methyl Cation, Methyl Anion, and Methyl Radical Intermediates .txt", "text": "So this guy has no electrons in the one s orbital."}, {"title": "Methyl Cation, Methyl Anion, and Methyl Radical Intermediates .txt", "text": "So that means it will be very active and will tend to act as a lewis acid."}, {"title": "Methyl Cation, Methyl Anion, and Methyl Radical Intermediates .txt", "text": "Now, this methyl and ion, since now it has a pair of electrons inside its orbital, it will tend to act as a lewis base donating those electrons."}, {"title": "Methyl Cation, Methyl Anion, and Methyl Radical Intermediates .txt", "text": "And because it has one more electron than it should in its neutral states, it has a negative one charge."}, {"title": "Methyl Cation, Methyl Anion, and Methyl Radical Intermediates .txt", "text": "So let's look at the third type of reaction with the methane molecule."}, {"title": "Methyl Cation, Methyl Anion, and Methyl Radical Intermediates .txt", "text": "In this reaction, the following ch bond associates."}, {"title": "Methyl Cation, Methyl Anion, and Methyl Radical Intermediates .txt", "text": "But it associates in a way such that one electron goes onto the carbon and one electron goes onto the H atom."}, {"title": "Methyl Cation, Methyl Anion, and Methyl Radical Intermediates .txt", "text": "So we get the following two radicals."}, {"title": "Methyl Cation, Methyl Anion, and Methyl Radical Intermediates .txt", "text": "We get the methyl radical and the H radical."}, {"title": "Methyl Cation, Methyl Anion, and Methyl Radical Intermediates .txt", "text": "So each molecule has one electron in its orbital."}, {"title": "Methyl Cation, Methyl Anion, and Methyl Radical Intermediates .txt", "text": "So now let's examine the three dimensional shapes of these reactive intermediates, and let's compare and contrast them."}, {"title": "Methyl Cation, Methyl Anion, and Methyl Radical Intermediates .txt", "text": "So let's go back to the methylcanion."}, {"title": "Methyl Cation, Methyl Anion, and Methyl Radical Intermediates .txt", "text": "So, I said earlier that this carbon will have an extra or an empty two p orbital."}, {"title": "Methyl Cation, Methyl Anion, and Methyl Radical Intermediates .txt", "text": "And because it has an empty two p orbital, it will act as a lewis acid."}, {"title": "Methyl Cation, Methyl Anion, and Methyl Radical Intermediates .txt", "text": "So let's see what that means."}, {"title": "Methyl Cation, Methyl Anion, and Methyl Radical Intermediates .txt", "text": "Notice also that it has three identical ch bonds."}, {"title": "Methyl Cation, Methyl Anion, and Methyl Radical Intermediates .txt", "text": "And that means this carbon will be SP two hybridized."}, {"title": "Methyl Cation, Methyl Anion, and Methyl Radical Intermediates .txt", "text": "So all these bonds will be SP two hybridized."}, {"title": "Methyl Cation, Methyl Anion, and Methyl Radical Intermediates .txt", "text": "And that means that all these bonds will lie on the same plane, let's say the XY plane."}, {"title": "Methyl Cation, Methyl Anion, and Methyl Radical Intermediates .txt", "text": "And the angle."}, {"title": "Methyl Cation, Methyl Anion, and Methyl Radical Intermediates .txt", "text": "Since we have three angles here, the angle between each adjacent ch bond will be 120 degrees."}, {"title": "Methyl Cation, Methyl Anion, and Methyl Radical Intermediates .txt", "text": "So this guy is 120."}, {"title": "Methyl Cation, Methyl Anion, and Methyl Radical Intermediates .txt", "text": "This angle is 120."}, {"title": "Methyl Cation, Methyl Anion, and Methyl Radical Intermediates .txt", "text": "And the angle in the back is also 120."}, {"title": "Methyl Cation, Methyl Anion, and Methyl Radical Intermediates .txt", "text": "Now, this line, the solid line, simply means the H is coming out of the board."}, {"title": "Methyl Cation, Methyl Anion, and Methyl Radical Intermediates .txt", "text": "The dashed line simply means the H is going into the board."}, {"title": "Methyl Cation, Methyl Anion, and Methyl Radical Intermediates .txt", "text": "Notice this pure two p orbital."}, {"title": "Methyl Cation, Methyl Anion, and Methyl Radical Intermediates .txt", "text": "This orbital is not SP two hybridized."}, {"title": "Methyl Cation, Methyl Anion, and Methyl Radical Intermediates .txt", "text": "This is a pure two p orbital."}, {"title": "Methyl Cation, Methyl Anion, and Methyl Radical Intermediates .txt", "text": "And that's exactly why this guy will act as a lewis acid."}, {"title": "Methyl Cation, Methyl Anion, and Methyl Radical Intermediates .txt", "text": "So if you take this molecule or atom and combine it with this molecule, this lewis base will tend to donate this pair of electrons to this orbital forming back our methane molecule."}, {"title": "Methyl Cation, Methyl Anion, and Methyl Radical Intermediates .txt", "text": "So now let's look at the methylamion."}, {"title": "Methyl Cation, Methyl Anion, and Methyl Radical Intermediates .txt", "text": "Now, we have a similar picture, but we have a pair of electrons within this two p orbital."}, {"title": "Methyl Cation, Methyl Anion, and Methyl Radical Intermediates .txt", "text": "And that means the pair of electrons will be found within this green positive region."}, {"title": "Methyl Cation, Methyl Anion, and Methyl Radical Intermediates .txt", "text": "And now we're no longer going to have SP two hybridized orbitals."}, {"title": "Methyl Cation, Methyl Anion, and Methyl Radical Intermediates .txt", "text": "In fact, this pair of electrons will act as if it was a bond because this pair of electrons will increase the negative charge, thereby increasing the electron density."}, {"title": "Methyl Cation, Methyl Anion, and Methyl Radical Intermediates .txt", "text": "And this will make the ch bonds move downward in an umbrella like fashion."}, {"title": "Methyl Cation, Methyl Anion, and Methyl Radical Intermediates .txt", "text": "So now our bonds are going to be very close to SP three hybridized."}, {"title": "Methyl Cation, Methyl Anion, and Methyl Radical Intermediates .txt", "text": "So we're no longer at SP two."}, {"title": "Methyl Cation, Methyl Anion, and Methyl Radical Intermediates .txt", "text": "We're SP three in this methyl, anion molecule."}, {"title": "Methyl Cation, Methyl Anion, and Methyl Radical Intermediates .txt", "text": "And now this pair of electrons will tend to act as a lewis base, donating these two electrons to some other atom."}, {"title": "Methyl Cation, Methyl Anion, and Methyl Radical Intermediates .txt", "text": "Now let's look at the final methyl radical."}, {"title": "Methyl Cation, Methyl Anion, and Methyl Radical Intermediates .txt", "text": "Now, the methyl radical is a combination of the following two drawings."}, {"title": "Methyl Cation, Methyl Anion, and Methyl Radical Intermediates .txt", "text": "Now, at one given point, it's in this state, and another given point, it's in this state."}, {"title": "Methyl Cation, Methyl Anion, and Methyl Radical Intermediates .txt", "text": "So it inverts from this form to this form."}, {"title": "Methyl Cation, Methyl Anion, and Methyl Radical Intermediates .txt", "text": "So it exists somewhere in between."}, {"title": "Methyl Cation, Methyl Anion, and Methyl Radical Intermediates .txt", "text": "And in fact, we can approximate that the three dimensional picture of our methyl radical looks something like this."}, {"title": "Methyl Cation, Methyl Anion, and Methyl Radical Intermediates .txt", "text": "So it's very similar to this methylcat ion."}, {"title": "Methyl Cation, Methyl Anion, and Methyl Radical Intermediates .txt", "text": "And for most purposes, we can approximate that this has the same exact three dimensional drawing as this methylcat ion."}, {"title": "Methyl Cation, Methyl Anion, and Methyl Radical Intermediates .txt", "text": "So we assume for the most part that all these bonds are SP two hybridized."}, {"title": "Methyl Cation, Methyl Anion, and Methyl Radical Intermediates .txt", "text": "In other words, because we only have one electron."}, {"title": "Methyl Cation, Methyl Anion, and Methyl Radical Intermediates .txt", "text": "And now two, that one electron does not have enough power to bend this shape as much as these two electrons bend the shape here."}, {"title": "Methyl Cation, Methyl Anion, and Methyl Radical Intermediates .txt", "text": "So they will exist between this and this guy."}, {"title": "Methyl Cation, Methyl Anion, and Methyl Radical Intermediates .txt", "text": "And an approximation somewhere in between is this drawing here."}, {"title": "Methyl Cation, Methyl Anion, and Methyl Radical Intermediates .txt", "text": "So, once again, all these three molecules are very reactive."}, {"title": "Methyl Cation, Methyl Anion, and Methyl Radical Intermediates .txt", "text": "They're called reactive income medians."}, {"title": "Methyl Cation, Methyl Anion, and Methyl Radical Intermediates .txt", "text": "And they won't persist in a stable state for a very long time."}, {"title": "Methyl Cation, Methyl Anion, and Methyl Radical Intermediates .txt", "text": "They will exist for a very short time."}, {"title": "Methyl Cation, Methyl Anion, and Methyl Radical Intermediates .txt", "text": "They will either react with these molecules to produce back our product, our reactants, or they will react with other molecules to produce other compounds."}, {"title": "Bonding and Antibonding Molecular Orbitals .txt", "text": "So we began our discussion on molecular orbitals."}, {"title": "Bonding and Antibonding Molecular Orbitals .txt", "text": "And thus far, we've said that, according to quantum mechanics, the number of atomic orbitals that we're combining must exactly equal the number of molecular orbitals that we are forming."}, {"title": "Bonding and Antibonding Molecular Orbitals .txt", "text": "Once again, the number of orbitals you are combining must equal the number that you are forming."}, {"title": "Bonding and Antibonding Molecular Orbitals .txt", "text": "Now."}, {"title": "Bonding and Antibonding Molecular Orbitals .txt", "text": "So far, we have tried to combine the one s atomic orbitals of two identical H atoms."}, {"title": "Bonding and Antibonding Molecular Orbitals .txt", "text": "So they're both neutral."}, {"title": "Bonding and Antibonding Molecular Orbitals .txt", "text": "That means they have one electron and one proton each."}, {"title": "Bonding and Antibonding Molecular Orbitals .txt", "text": "And so far we saw that when we combine these two atomic orbitals of the one of the H atom one that's orbitals, we form something called a five bonding molecular orbital."}, {"title": "Bonding and Antibonding Molecular Orbitals .txt", "text": "Or simply a bonding molecular orbital."}, {"title": "Bonding and Antibonding Molecular Orbitals .txt", "text": "And we said that the energy of this molecular orbital, of the Bonding molecular orbital, is lower than either of the atomic orbitals from which we're forming."}, {"title": "Bonding and Antibonding Molecular Orbitals .txt", "text": "So, according to this diagram, we see that the y axis is energy."}, {"title": "Bonding and Antibonding Molecular Orbitals .txt", "text": "And so the lower we go, the less energy we have."}, {"title": "Bonding and Antibonding Molecular Orbitals .txt", "text": "The higher we go, the more energy we have."}, {"title": "Bonding and Antibonding Molecular Orbitals .txt", "text": "Now, once again, according to Quantum Mechanics, if we begin with two atomic orbitals, we have to form two molecular orbitals."}, {"title": "Bonding and Antibonding Molecular Orbitals .txt", "text": "So far we've only seen one."}, {"title": "Bonding and Antibonding Molecular Orbitals .txt", "text": "Well, the second one is shown right up here, and it's called the phi antibonding molecular orbital."}, {"title": "Bonding and Antibonding Molecular Orbitals .txt", "text": "And we'll see why it's called antibonding in just a second."}, {"title": "Bonding and Antibonding Molecular Orbitals .txt", "text": "The first thing you have to notice about this antibody molecular orbital."}, {"title": "Bonding and Antibonding Molecular Orbitals .txt", "text": "If that is higher in energy than either of these guys, So let's move to this diagram here."}, {"title": "Bonding and Antibonding Molecular Orbitals .txt", "text": "So here we have the combination of two of these atomic orbitals to form our fine bonding molecular orbital."}, {"title": "Bonding and Antibonding Molecular Orbitals .txt", "text": "Now, notice the following this positive and negative sign designates the sign of the Orbitals."}, {"title": "Bonding and Antibonding Molecular Orbitals .txt", "text": "And Orbitals are simply wave functions."}, {"title": "Bonding and Antibonding Molecular Orbitals .txt", "text": "So these guys represent the sign of the orbitals or the wave functions."}, {"title": "Bonding and Antibonding Molecular Orbitals .txt", "text": "They do not represent charge."}, {"title": "Bonding and Antibonding Molecular Orbitals .txt", "text": "Now."}, {"title": "Bonding and Antibonding Molecular Orbitals .txt", "text": "So when we combine these two guys, what we're combining is we're combining two orbitals."}, {"title": "Bonding and Antibonding Molecular Orbitals .txt", "text": "Two?"}, {"title": "Bonding and Antibonding Molecular Orbitals .txt", "text": "One as orbitals of the same sign and we form an overlapping molecular orbital called the bonding."}, {"title": "Bonding and Antibonding Molecular Orbitals .txt", "text": "Molecular orbital."}, {"title": "Bonding and Antibonding Molecular Orbitals .txt", "text": "So to better understand what this is, let's draw out our proton."}, {"title": "Bonding and Antibonding Molecular Orbitals .txt", "text": "An electron diagram."}, {"title": "Bonding and Antibonding Molecular Orbitals .txt", "text": "So here we have the nucleus of our atom."}, {"title": "Bonding and Antibonding Molecular Orbitals .txt", "text": "H A."}, {"title": "Bonding and Antibonding Molecular Orbitals .txt", "text": "And here we have the nucleus of our atom HB."}, {"title": "Bonding and Antibonding Molecular Orbitals .txt", "text": "Now the two electrons are found somewhere in the middle."}, {"title": "Bonding and Antibonding Molecular Orbitals .txt", "text": "Now, what these electrons do is they stabilize these protons."}, {"title": "Bonding and Antibonding Molecular Orbitals .txt", "text": "In other words, let's suppose we take these two electrons away."}, {"title": "Bonding and Antibonding Molecular Orbitals .txt", "text": "According to Coulomb's law, these two positively charged nuclei would begin to repel one another and would travel in opposite directions."}, {"title": "Bonding and Antibonding Molecular Orbitals .txt", "text": "But what these electrons do is they stabilize these two positively charged nuclei."}, {"title": "Bonding and Antibonding Molecular Orbitals .txt", "text": "And because this nucleus is attracted to these two electrons, and this nucleus is attracted to these two electrons, these two protons or nuclei will be held in place, and therefore a bond or a codalin bond will be formed."}, {"title": "Bonding and Antibonding Molecular Orbitals .txt", "text": "And this is known as the bonding molecular orbital."}, {"title": "Bonding and Antibonding Molecular Orbitals .txt", "text": "So let's look at the Creation of the Antibinding molecular orbital."}, {"title": "Bonding and Antibonding Molecular Orbitals .txt", "text": "Now, what this means is that we're combining two orbitals where one of the orbitals one of the one s orbital is of a positive sign and the other atomic orbital, the other one s atomic orbital is of a negative sign."}, {"title": "Bonding and Antibonding Molecular Orbitals .txt", "text": "And remember, orbitals are wave functions."}, {"title": "Bonding and Antibonding Molecular Orbitals .txt", "text": "And that simply means that when our orbitals go from a positive sign to a negative sign, they must go through the .0."}, {"title": "Bonding and Antibonding Molecular Orbitals .txt", "text": "And this is known as the Nodal plane."}, {"title": "Bonding and Antibonding Molecular Orbitals .txt", "text": "And we'll see what that is in effect."}, {"title": "Bonding and Antibonding Molecular Orbitals .txt", "text": "So we're combining these two oppositely charged One s atomic orbitals."}, {"title": "Bonding and Antibonding Molecular Orbitals .txt", "text": "So We Form a positively Charged atomic orbital and a Negative charged atomic orbital."}, {"title": "Bonding and Antibonding Molecular Orbitals .txt", "text": "And this is altogether known as the molecular orbital."}, {"title": "Bonding and Antibonding Molecular Orbitals .txt", "text": "And notice what this region here in the middle is."}, {"title": "Bonding and Antibonding Molecular Orbitals .txt", "text": "This is called the nodal plane."}, {"title": "Bonding and Antibonding Molecular Orbitals .txt", "text": "Or simply the node."}, {"title": "Bonding and Antibonding Molecular Orbitals .txt", "text": "This is the .0."}, {"title": "Bonding and Antibonding Molecular Orbitals .txt", "text": "In other words, nodal plane is the region where the electron density is zero."}, {"title": "Bonding and Antibonding Molecular Orbitals .txt", "text": "What that means is that we will Never find an electron or electrons in this region here."}, {"title": "Bonding and Antibonding Molecular Orbitals .txt", "text": "And so let's see What that means by drawing out our Proton electron diagram."}, {"title": "Bonding and Antibonding Molecular Orbitals .txt", "text": "So here we have two protons."}, {"title": "Bonding and Antibonding Molecular Orbitals .txt", "text": "Our nucleus one, our nucleus two."}, {"title": "Bonding and Antibonding Molecular Orbitals .txt", "text": "And electrons."}, {"title": "Bonding and Antibonding Molecular Orbitals .txt", "text": "Now, because The Electrons can Never Be found in this region here, that means that there is nothing stabilizing the electrostatic repulsion between these two positively charged nuclei."}, {"title": "Bonding and Antibonding Molecular Orbitals .txt", "text": "And that means in this case, in the Anti bonding case, the Two nuclei will actually try to Repel One another, and Our Bond Will be broken."}, {"title": "Bonding and Antibonding Molecular Orbitals .txt", "text": "And that's exactly why it's called antibonding."}, {"title": "Bonding and Antibonding Molecular Orbitals .txt", "text": "Our bond is broken in the antibonding molecular orbital."}, {"title": "Bonding and Antibonding Molecular Orbitals .txt", "text": "So, once again, to Recap, electrons found In The bonding molecular orbitals will Stabilize One another because of the stabilizing formation of electrons and protons."}, {"title": "Bonding and Antibonding Molecular Orbitals .txt", "text": "And this will tend to hold the atoms together."}, {"title": "Bonding and Antibonding Molecular Orbitals .txt", "text": "Electrons In The antibinding molecular orbital cause the Dissociation of the atoms."}, {"title": "Bonding and Antibonding Molecular Orbitals .txt", "text": "Because of this Noteplane region, electrons cannot be found in the Nodal Plane region, as that means these two protons will repel and they will move away from one Another, dissociating breaking that covalent Bond."}, {"title": "Bonding and Antibonding Molecular Orbitals .txt", "text": "So note this a important point."}, {"title": "Bonding and Antibonding Molecular Orbitals .txt", "text": "Electrons can be found both in the bonding and the antibonding molecular orbitals."}, {"title": "Bonding and Antibonding Molecular Orbitals .txt", "text": "However, there's a big difference between the bonding and the antibodies."}, {"title": "Bonding and Antibonding Molecular Orbitals .txt", "text": "When the electrons are in the bonding orbital the bonding molecular orbital."}, {"title": "Bonding and Antibonding Molecular Orbitals .txt", "text": "They will stabilize the bond."}, {"title": "Bonding and Antibonding Molecular Orbitals .txt", "text": "When the electrons into the antibonding region, the antiboming molecular orbital, those electrons will tend to destabilize our bond, and our bond will tend to dissociate or break."}, {"title": "Introduction to Lewis Structure.txt", "text": "So in this lecture, we're going to talk about Lewis structures."}, {"title": "Introduction to Lewis Structure.txt", "text": "Now, Lewis structures are simply shortcut depictions of electrons surrounding our atoms or molecules."}, {"title": "Introduction to Lewis Structure.txt", "text": "So let's begin with examples."}, {"title": "Introduction to Lewis Structure.txt", "text": "So let's suppose we have this fluorine atom."}, {"title": "Introduction to Lewis Structure.txt", "text": "Now, a neutral fluorine atom has nonprofit tons and nine electrons."}, {"title": "Introduction to Lewis Structure.txt", "text": "And the electron configuration of our fluorine atom is as follows."}, {"title": "Introduction to Lewis Structure.txt", "text": "Two electrons will go into the one s orbital, two electrons will go into the two s orbital."}, {"title": "Introduction to Lewis Structure.txt", "text": "Two electrons will go into the two PX, two electrons will go into the two PY, and one electron will go into the two PV."}, {"title": "Introduction to Lewis Structure.txt", "text": "So we have a total of 2222 and one nine electrons."}, {"title": "Introduction to Lewis Structure.txt", "text": "So if we were to actually draw out the atomic orbitals of our fluorine atom, we would get the following picture."}, {"title": "Introduction to Lewis Structure.txt", "text": "So within this picture, our one s orbital is found within our two s orbital."}, {"title": "Introduction to Lewis Structure.txt", "text": "So I did not draw it."}, {"title": "Introduction to Lewis Structure.txt", "text": "But this circular series here is our two s orbital."}, {"title": "Introduction to Lewis Structure.txt", "text": "So we're placing two electrons within this two x orbital shown here."}, {"title": "Introduction to Lewis Structure.txt", "text": "Now we have the two p x orbital shown here."}, {"title": "Introduction to Lewis Structure.txt", "text": "We have the two p y orbital shown here, and the two PZ orbital shown here, coming out of the board and going into the board."}, {"title": "Introduction to Lewis Structure.txt", "text": "So this is the full depiction of the atomic orbitals of flooring."}, {"title": "Introduction to Lewis Structure.txt", "text": "Now, this is very tedious and will take a long time to draw out when you're solving problems."}, {"title": "Introduction to Lewis Structure.txt", "text": "So that's why the Lewis Structure method was developed."}, {"title": "Introduction to Lewis Structure.txt", "text": "And what we do in the Lewis Structure method is the following."}, {"title": "Introduction to Lewis Structure.txt", "text": "We only worry about the balanced electrons."}, {"title": "Introduction to Lewis Structure.txt", "text": "The balanced electrons are the electrons found in the outermost subshell, and this is this guy here."}, {"title": "Introduction to Lewis Structure.txt", "text": "So this N equals to a principal number will include all these electrons here."}, {"title": "Introduction to Lewis Structure.txt", "text": "So that's two plus two plus two plus one."}, {"title": "Introduction to Lewis Structure.txt", "text": "That's seven electrons in the balance shell in the balanced electron shell."}, {"title": "Introduction to Lewis Structure.txt", "text": "So that means we only include these guys."}, {"title": "Introduction to Lewis Structure.txt", "text": "And these one s you could think of as being inside the flooring."}, {"title": "Introduction to Lewis Structure.txt", "text": "So they're not depicted."}, {"title": "Introduction to Lewis Structure.txt", "text": "So we only worry about these guys."}, {"title": "Introduction to Lewis Structure.txt", "text": "So two will go to two s.\nSo two here, two will go into two PX, two go here, two goes to two PY, which go here, and one goes into here."}, {"title": "Introduction to Lewis Structure.txt", "text": "Now, notice it doesn't really matter."}, {"title": "Introduction to Lewis Structure.txt", "text": "I could have took one away from here and placed one on the bottom."}, {"title": "Introduction to Lewis Structure.txt", "text": "As long as I have two two and a two and a one in any arrangement, I will have the Lewis Structure for flooring."}, {"title": "Introduction to Lewis Structure.txt", "text": "And the same thing could be said for oxygen."}, {"title": "Introduction to Lewis Structure.txt", "text": "So oxygen has eight protons, and that means a neutral oxygen has eight electrons."}, {"title": "Introduction to Lewis Structure.txt", "text": "So let's once again draw our electron configuration for oxygen."}, {"title": "Introduction to Lewis Structure.txt", "text": "So we have one s. So two electrons go to the one s.\nWe have two s, two electrons go to the two s. We have two PX and two PY and two PV."}, {"title": "Introduction to Lewis Structure.txt", "text": "So two go in here, one goes in here, and one goes in the last two PZ."}, {"title": "Introduction to Lewis Structure.txt", "text": "Now, once again, we draw out the full atomic orbital picture for our oxygen."}, {"title": "Introduction to Lewis Structure.txt", "text": "So two go into the one S, which we did not draw because it's within our two S. So two go into the two S.\nSo here's our sphere to go inside the two S, two go to the two PX."}, {"title": "Introduction to Lewis Structure.txt", "text": "So two go into the two PX."}, {"title": "Introduction to Lewis Structure.txt", "text": "One goes into two PY."}, {"title": "Introduction to Lewis Structure.txt", "text": "So one goes into this one, and finally, one goes into the two PZ."}, {"title": "Introduction to Lewis Structure.txt", "text": "So once again, this took a lot of time."}, {"title": "Introduction to Lewis Structure.txt", "text": "There's a shortcut method now that we know the Lewis Structure method."}, {"title": "Introduction to Lewis Structure.txt", "text": "And so we draw an oxygen atom."}, {"title": "Introduction to Lewis Structure.txt", "text": "So the o here, we pretend that we put two electrons inside the oxygen, which means we put the two one S electrons inside the oxygen."}, {"title": "Introduction to Lewis Structure.txt", "text": "And now we only worry about our balanced electrons, the outermost electrons."}, {"title": "Introduction to Lewis Structure.txt", "text": "And so we need to place two electrons that represent the two S. So you could either place them here, here, or here or here."}, {"title": "Introduction to Lewis Structure.txt", "text": "I place them, say here."}, {"title": "Introduction to Lewis Structure.txt", "text": "Now we have the two PX, so I placed them here."}, {"title": "Introduction to Lewis Structure.txt", "text": "Now I have the two P-Y-I placed one here and two PD."}, {"title": "Introduction to Lewis Structure.txt", "text": "I placed one here."}, {"title": "Introduction to Lewis Structure.txt", "text": "Now, once again, it does not matter where I place this electron pair."}, {"title": "Introduction to Lewis Structure.txt", "text": "I could place this electron pair here, and I could place this one here, and I could switch them around in any way I want to, as long as I have one pair, one pair and two singles."}, {"title": "Introduction to Lewis Structure.txt", "text": "So this is my depiction for oxygen."}, {"title": "Introduction to Lewis Structure.txt", "text": "So Lewis structure for fluorine and Lewis structure for oxygen."}, {"title": "Introduction to Lewis Structure.txt", "text": "Now."}, {"title": "Introduction to Lewis Structure.txt", "text": "I could also draw Lewis structures for molecules."}, {"title": "Introduction to Lewis Structure.txt", "text": "So suppose I have two fluorine atoms."}, {"title": "Introduction to Lewis Structure.txt", "text": "So I take these two fluorine atoms, so two of them, and they interact with one another to form a diatomic fluoride."}, {"title": "Introduction to Lewis Structure.txt", "text": "Now, what that basically means is that two of these guys will orient in a way such that these two single electrons will interact and they will form a cobaltin bond in which there is a sharing of electrons."}, {"title": "Introduction to Lewis Structure.txt", "text": "So that means this electron will be donated to this orbital, and this electron will be donated to this orbital."}, {"title": "Introduction to Lewis Structure.txt", "text": "So two fluoride will interact to form an electron configuration of the nearest noble gas."}, {"title": "Introduction to Lewis Structure.txt", "text": "The nearest noble gas is neon."}, {"title": "Introduction to Lewis Structure.txt", "text": "Neon has ten protons and ten electrons, while fluorine has or a single fluorine has nine electrons and nine protons."}, {"title": "Introduction to Lewis Structure.txt", "text": "So since one of the fluorine will donate an electron to this guy, this will gain one electron."}, {"title": "Introduction to Lewis Structure.txt", "text": "So this will gain ten electron, half ten electrons, and it will form electron configuration of our neon noble gas."}, {"title": "Introduction to Lewis Structure.txt", "text": "And likewise, the same story for this flooring."}, {"title": "Introduction to Lewis Structure.txt", "text": "And once again, this picture can be depicted in a shortcut way using this flooring or Lewis Structure depiction for flooring."}, {"title": "Introduction to Lewis Structure.txt", "text": "So, once again, two electrons here, here, and here, like we drew here."}, {"title": "Introduction to Lewis Structure.txt", "text": "So this represents the one S, this the two PX, the two PY and the two PZ."}, {"title": "Introduction to Lewis Structure.txt", "text": "So we orient them, and these electrons are shared."}, {"title": "Introduction to Lewis Structure.txt", "text": "And so now we should actually redraw these guys, because since there's a sharing of electrons, they should draw we should draw them like this so that now each one has eight electrons as the valid electrons plus two one s electrons."}, {"title": "Introduction to Lewis Structure.txt", "text": "So each guy has ten electrons, and that means each guy have each flooring has a has achieved electron configuration of a noble gas."}, {"title": "Introduction to Lewis Structure.txt", "text": "Now, this is the same thing as writing this guy."}, {"title": "Introduction to Lewis Structure.txt", "text": "Now, this is even a more shortcut method, because now we don't have to add these electrons on the outside."}, {"title": "Introduction to Lewis Structure.txt", "text": "We kind of assume that they are there, but we don't draw them."}, {"title": "Introduction to Lewis Structure.txt", "text": "What we do draw is this line here."}, {"title": "Introduction to Lewis Structure.txt", "text": "This line simply means that there is an equal sharing of electrons."}, {"title": "Introduction to Lewis Structure.txt", "text": "And this can further be depicted by simply writing f two."}, {"title": "Introduction to Lewis Structure.txt", "text": "And this simply means that there are two foreign atoms and they're interacting in an equivalent way."}, {"title": "Introduction to Lewis Structure.txt", "text": "So they're sharing these two electrons."}, {"title": "Introduction to Lewis Structure.txt", "text": "So this same exact method can be written for oxygen."}, {"title": "Introduction to Lewis Structure.txt", "text": "When two oxygen atoms interact, they form a double bond."}, {"title": "Introduction to Lewis Structure.txt", "text": "And these guys are both shared equally, so they form the electron confi"}, {"title": "Heat Capacity, Specific Heat Capacity and Molar Heat Capacity.txt", "text": "Heat Capacity is not the Mounted heat that Im Istoria Object remember."}, {"title": "Heat Capacity, Specific Heat Capacity and Molar Heat Capacity.txt", "text": "Heat Is the fall of Energy from a high Temperature to a Low Temperature."}, {"title": "Heat Capacity, Specific Heat Capacity and Molar Heat Capacity.txt", "text": "So what Heat Capacity actually is it's the Amount of Energy Quined to change an Object Temperature by some Amount."}, {"title": "Heat Capacity, Specific Heat Capacity and Molar Heat Capacity.txt", "text": "So this is the formula of Le Capacity."}, {"title": "Heat Capacity, Specific Heat Capacity and Molar Heat Capacity.txt", "text": "Where Capital ce is Heat capacity that equal the change in Energy or Energy Imp\u00f4t overchangein Temperature and The Units or Jel Sava jesper celles and the reason we could interchange calvince is because Changes and Temperature on the Scales are equivalent s five degree change on a cabinscaleisoa five degree change on a Celsa scale Suppose we take an object thel and we want to find the Energy Importat required to change this Object Temperature by Five degrees Celsius the way we find that is well, use this formula."}, {"title": "Heat Capacity, Specific Heat Capacity and Molar Heat Capacity.txt", "text": "Look of the particular se value for this substance we Plat get in we plan the change in Temperature In and we find the Energy input required to effect this object and Change Is objective degrees Cel siet Capacity is an extensive Property and that simply means if we Have some object the Sea shell in this hand and the 2\u1d48 Object seashell twice the Size and this one the Mathavenergy required to change the largest sech elte five the grease less will be twice as large as this one and that means if the Taquine as large for the Same Changing Temperature Will Be Large as well, so Heat Capacity or Sea changes with a change in Size of Our System."}, {"title": "Heat Capacity, Specific Heat Capacity and Molar Heat Capacity.txt", "text": "So it's An Extent of property number intense of properties of Those Properties such as Temperature that Do not Change when there is A change in Size two types of Het Capacitives that exist constant Valie Capacitives or Ce Laura tian constant Pressure het Capacitives parano."}, {"title": "Heat Capacity, Specific Heat Capacity and Molar Heat Capacity.txt", "text": "Let's talk about Constant Valetcapacities."}, {"title": "Heat Capacity, Specific Heat Capacity and Molar Heat Capacity.txt", "text": "Let's go back to our First War Terminant."}, {"title": "Heat Capacity, Specific Heat Capacity and Molar Heat Capacity.txt", "text": "Which Basically States that Total change Energy Bar System is equal to the change in Internal Angier System plus Pv Work Done so with this Circle is Our System and all these Malts are famil tou Circle."}, {"title": "Heat Capacity, Specific Heat Capacity and Molar Heat Capacity.txt", "text": "The change in Energy is equal to the Changing all the potential Energies And Conn etic Energydata System and the work done or the work Done by these molecules on the Surrounding Molecules in Expanding or Compressing this System here."}, {"title": "Heat Capacity, Specific Heat Capacity and Molar Heat Capacity.txt", "text": "So when there is a Constant volume, lots look our equation this guy goes to zero because at Constant volume."}, {"title": "Heat Capacity, Specific Heat Capacity and Molar Heat Capacity.txt", "text": "What Happens to change in Pressure."}, {"title": "Heat Capacity, Specific Heat Capacity and Molar Heat Capacity.txt", "text": "Well, it Zero so Change and Energy Is simply change in Internal Energy."}, {"title": "Heat Capacity, Specific Heat Capacity and Molar Heat Capacity.txt", "text": "So there is a Transfert Energy into a system."}, {"title": "Heat Capacity, Specific Heat Capacity and Molar Heat Capacity.txt", "text": "All the Energy is transferer In Increasing Internal Energy Bar System and Because Internal Energy Is related to Kinetic Energy and Kinetic Energy is Related to Temperature increasing Internal Energy increases America Energy and that Increases Temperature."}, {"title": "Heat Capacity, Specific Heat Capacity and Molar Heat Capacity.txt", "text": "So all the Energy In it Cas Valium Goes in Through Increasing Temperature no Pv Work is Done no expansion is done it constant pressure."}, {"title": "Heat Capacity, Specific Heat Capacity and Molar Heat Capacity.txt", "text": "However according to the ideal gasa temperature must change as well and a value must change."}, {"title": "Heat Capacity, Specific Heat Capacity and Molar Heat Capacity.txt", "text": "So that means that some energy goes into increasing temperature and some energy goes into increasing value."}, {"title": "Heat Capacity, Specific Heat Capacity and Molar Heat Capacity.txt", "text": "Okay, so this term is no longer zero this term exists and work is done."}, {"title": "Heat Capacity, Specific Heat Capacity and Molar Heat Capacity.txt", "text": "And that's why p values or the heat capacity at constant pressure values are usually larger than constant valium hit capacity values."}, {"title": "Heat Capacity, Specific Heat Capacity and Molar Heat Capacity.txt", "text": "And that's because if we go back to this term here."}, {"title": "Heat Capacity, Specific Heat Capacity and Molar Heat Capacity.txt", "text": "And we look at this equation for consent valium this last part laser for this guy we simply plug in change in new for the 2\u1d48 question however we have this last term this here this anti secher will be greater."}, {"title": "Heat Capacity, Specific Heat Capacity and Molar Heat Capacity.txt", "text": "So some number over changent temperature verses a smaller number over the same changer temperature will give a smaller sea value."}, {"title": "Heat Capacity, Specific Heat Capacity and Molar Heat Capacity.txt", "text": "So this cy will be smaller than this qui srecoacapacity is an extensive property."}, {"title": "Heat Capacity, Specific Heat Capacity and Molar Heat Capacity.txt", "text": "So an will increase with increase and sides of the system."}, {"title": "Heat Capacity, Specific Heat Capacity and Molar Heat Capacity.txt", "text": "No specific capacity and mali capacitives were developed a intense of properties."}, {"title": "Heat Capacity, Specific Heat Capacity and Molar Heat Capacity.txt", "text": "And that means that these two guys will save the same when the size will increase let's definie capacity specific capacity is the month of algerie to change a specific and multi mass of an object by some temperature."}, {"title": "Heat Capacity, Specific Heat Capacity and Molar Heat Capacity.txt", "text": "The formula is lower."}, {"title": "Heat Capacity, Specific Heat Capacity and Molar Heat Capacity.txt", "text": "Ces equal to put an energy over changing seperature times mass."}, {"title": "Heat Capacity, Specific Heat Capacity and Molar Heat Capacity.txt", "text": "Now, we have this mass component in arden ome."}, {"title": "Heat Capacity, Specific Heat Capacity and Molar Heat Capacity.txt", "text": "And the units are jelspergamtimes calvin or calorifornimes celles now it's an sens of property."}, {"title": "Heat Capacity, Specific Heat Capacity and Molar Heat Capacity.txt", "text": "Why well, because is an extensive property."}, {"title": "Heat Capacity, Specific Heat Capacity and Molar Heat Capacity.txt", "text": "And is an extent of property."}, {"title": "Heat Capacity, Specific Heat Capacity and Molar Heat Capacity.txt", "text": "And from our lecture on extensive intent of properties, we saw that will we divide and extent of property by another extent of property, we get an in sets of property."}, {"title": "Heat Capacity, Specific Heat Capacity and Molar Heat Capacity.txt", "text": "And that's because if you increase the size of the object qu increase and but cris by simera mount and sell the cu m ratio stars the same so stars the same."}, {"title": "Heat Capacity, Specific Heat Capacity and Molar Heat Capacity.txt", "text": "Or a specific et capacity stars the same."}, {"title": "Heat Capacity, Specific Heat Capacity and Molar Heat Capacity.txt", "text": "So let's define moloicapacity moloicapacity the mount of lj rir to change some mount a molles of an object by some temperature."}, {"title": "Heat Capacity, Specific Heat Capacity and Molar Heat Capacity.txt", "text": "And the formula is almost the same thing as this one except the mass is replaced with number of mills and kilogram gram is replaced by molle."}, {"title": "Heat Capacity, Specific Heat Capacity and Molar Heat Capacity.txt", "text": "Now once again this guy is also an intenseproperty because we divide xtensoroperty another extenso property this qu and radio stars the same."}, {"title": "Heat Capacity, Specific Heat Capacity and Molar Heat Capacity.txt", "text": "And so see our moller heat capacity also stars the same."}, {"title": "Partial Pressure Equilibrium Constant .txt", "text": "Now, in this lecture I'm going to really briefly talk about something called the partial pressure clearbium constant."}, {"title": "Partial Pressure Equilibrium Constant .txt", "text": "Now, I'm not going to go into much detail about this guy because I just want you to be aware that this guy exists."}, {"title": "Partial Pressure Equilibrium Constant .txt", "text": "Now if reactants and products are both in the gas state, we can still use the equilibrium constant and the expression equilibrium constant."}, {"title": "Partial Pressure Equilibrium Constant .txt", "text": "But now we have to incorporate the partial pressures of our gases."}, {"title": "Partial Pressure Equilibrium Constant .txt", "text": "For example, suppose we have the following reaction in which gas A react with gas B to produce gas C and gas D, where it lowercase A-B-C and D are the coefficients of each respective atom that represent the moles of each atom."}, {"title": "Partial Pressure Equilibrium Constant .txt", "text": "For example, lowercase a number of moles of A gas reacts with B number of moles of B gas produces C number of moles of C gas and B number of moles of D gas."}, {"title": "Partial Pressure Equilibrium Constant .txt", "text": "Now our equilibrium constant for this gaseous reaction is the following our equilibrium constant KP is equal to the partial pressure of our C of our gas product C to the C power."}, {"title": "Partial Pressure Equilibrium Constant .txt", "text": "Now that's lowercase C, an abia should represent it with the black marker."}, {"title": "Partial Pressure Equilibrium Constant .txt", "text": "So lowercase C times the partial pressure of D gas to the D coefficient."}, {"title": "Partial Pressure Equilibrium Constant .txt", "text": "So d exponent divided by the partial pressure of this gas A to the lowercase A power times the partial pressure of our B reactants our gas to the B lowercase B power."}, {"title": "Partial Pressure Equilibrium Constant .txt", "text": "And this is our equilibrium constant expression for gaseous reactions."}, {"title": "Partial Pressure Equilibrium Constant .txt", "text": "So it's almost the same."}, {"title": "Partial Pressure Equilibrium Constant .txt", "text": "But it's different in that now we're using partial pressures and not concentrations."}, {"title": "Molality Example .txt", "text": "Molality is simply another way of measuring the concentration of a solution."}, {"title": "Molality Example .txt", "text": "The symbol for molality is lowercase letter M and the formula is moles of solute over kilograms of solvent."}, {"title": "Molality Example .txt", "text": "Now let's do an example."}, {"title": "Molality Example .txt", "text": "Using molality."}, {"title": "Molality Example .txt", "text": "The question tells us that we have 90 grams of glucose and 200 grams of H 20."}, {"title": "Molality Example .txt", "text": "And we want to find the molality of the solution."}, {"title": "Molality Example .txt", "text": "We're basically taking glucose, the salute and water, the solvent."}, {"title": "Molality Example .txt", "text": "We're mixing it and we want to find the concentration."}, {"title": "Molality Example .txt", "text": "In terms of molality, the first step is to find the molecular weight of glucose."}, {"title": "Molality Example .txt", "text": "This will help us find the number of moles of glucose within our solution."}, {"title": "Molality Example .txt", "text": "The first step is to find the atomic weight of each atom and multiplied by each subscript."}, {"title": "Molality Example .txt", "text": "So the atomic weight of carbon is 12 grams/mol, the atomic weight of H is 1 gram/mol, and the atomic weight of oxygen is 16 grams/mol."}, {"title": "Molality Example .txt", "text": "So we multiply six by twelve, add that to twelve times one and add that to six times 16 and we get approximately 180 grams/mol."}, {"title": "Molality Example .txt", "text": "Now, using this number, we can take our 90 grams of glucose and find the number of moles."}, {"title": "Molality Example .txt", "text": "90 grams of glucose divided by 180 grams of glucose per mole gets us 0.5\nor one half moles of glucose."}, {"title": "Molality Example .txt", "text": "That's our number of moles within this solution."}, {"title": "Molality Example .txt", "text": "The final step is to use the formula for molality."}, {"title": "Molality Example .txt", "text": "Lowercase M for molality is equal to one half number of moles of salute divided by now notice we're getting 200 grams and molality ditosomality are moles per kilogram."}, {"title": "Molality Example .txt", "text": "So we have to convert 200 grams to kilogram."}, {"title": "Molality Example .txt", "text": "We get 0.2\nkilogram of H 20, the solvent, and we get 2.5 molality or moles per kilogram."}, {"title": "Molality Example .txt", "text": "And that's our final answer."}, {"title": "Halogens .txt", "text": "In this lecture we're going to talk about group seven, a elements, also known as group 17, according to our newer system."}, {"title": "Halogens .txt", "text": "Now, these guides are known as the halogens, and we're going to look at five halogens."}, {"title": "Halogens .txt", "text": "Now, fluorine, chlorine, bromine and iodine are all very common, non metallic halogens."}, {"title": "Halogens .txt", "text": "The thick talent, which is a metal lloyd, is the least common halogen, and that's called astonine with a symbol at."}, {"title": "Halogens .txt", "text": "Now, we're not even really talk about this guy too much because he's not very common."}, {"title": "Halogens .txt", "text": "But you should know that aside from these talents, there's also the thick talent called Astane."}, {"title": "Halogens .txt", "text": "Now, halogens in general are very radioactive."}, {"title": "Halogens .txt", "text": "And what that means is basically it reacts, or halogens react with even the most stable compounds causing damage."}, {"title": "Halogens .txt", "text": "For example, halogens are deadly to humans or other organisms."}, {"title": "Halogens .txt", "text": "And if we inhale some of the halogen gas, we will suffocate and die, because halogens react in our body in a very detrimental way."}, {"title": "Halogens .txt", "text": "Now let's look specifically at fluorine."}, {"title": "Halogens .txt", "text": "Now, fluorine exists in at room temperature in a diatomic gas form, f two form."}, {"title": "Halogens .txt", "text": "So if we inhale, for example, fluorine, the gas, that gas will cause damage in our body and we will suffocate."}, {"title": "Halogens .txt", "text": "Now, fluorine is the most electronegative atom out there."}, {"title": "Halogens .txt", "text": "In other words, it has the highest affinity for electrons."}, {"title": "Halogens .txt", "text": "It is more likely to take electrons away than any other atom."}, {"title": "Halogens .txt", "text": "Now, fluorine also only has one oxidation state, negative one."}, {"title": "Halogens .txt", "text": "And that means it only forms one bond."}, {"title": "Halogens .txt", "text": "No more, only one bond."}, {"title": "Halogens .txt", "text": "Now we'll see that chlorine, BromIn and iodine forms more than one bond."}, {"title": "Halogens .txt", "text": "But know that fluorine, the most electronegative atom, forms only one bond, and its oxidation state is negative one."}, {"title": "Halogens .txt", "text": "For example, it forms bonds with h. It forms bonds with NA and CA, but it only forms one bond."}, {"title": "Halogens .txt", "text": "Now let's look at chlorine."}, {"title": "Halogens .txt", "text": "Chlorine is a diatomic gas at room temperature, just like fluorine."}, {"title": "Halogens .txt", "text": "Bromine is a diatomic liquid at room temperature, and iodine is a diatomic solid at room temperature."}, {"title": "Halogens .txt", "text": "Now, these three guys, chlorine, bromine and iodine, unlike chlorine, can have an oxidation state of up to plus seven, and that means they can all form up to seven bonds."}, {"title": "Halogens .txt", "text": "The last important thing you should know about halogens is that halogens can react with the hion."}, {"title": "Halogens .txt", "text": "In other words, in aqueous state where waters are solvent, they can form acids, hydrofluoric acid, hydrochloric acid, hydrobromic acid, and so on."}, {"title": "Halogens .txt", "text": "All the halogens form acids."}, {"title": "Halogens .txt", "text": "And in fact, he is one of the acids out there."}, {"title": "Theoretical and Percent Yield .txt", "text": "Today we're going to talk about reactions and their yield."}, {"title": "Theoretical and Percent Yield .txt", "text": "Now, the amount of product produced when all the reactants are completely used up in other words, when our reaction runs to completion is known as the theoretical yield."}, {"title": "Theoretical and Percent Yield .txt", "text": "Note that most reactions don't actually run to completion and that's because our reactions usually reach equilibrium before any of the reactants are depleted and that means that theoretical yield will not be possible."}, {"title": "Theoretical and Percent Yield .txt", "text": "We'll get a number below theoretical yield and this number is known as the actual yield of our experiment."}, {"title": "Theoretical and Percent Yield .txt", "text": "Now, to see how far a reaction proceeded, in other words, how close it got to our theoretical yield we simply find actual yield and theoretical yield."}, {"title": "Theoretical and Percent Yield .txt", "text": "We divide two."}, {"title": "Theoretical and Percent Yield .txt", "text": "So actual yield divided by theoretical yield multiplies that by 100 to get our percent because otherwise this guy is a fraction and that will give you percent yield."}, {"title": "Theoretical and Percent Yield .txt", "text": "Now, let's look at the following reaction."}, {"title": "Theoretical and Percent Yield .txt", "text": "So in the following reaction, 1 mol of methane reacts with two moles of oxygen to produce 1 mol of carbon dioxide and two moles of water."}, {"title": "Theoretical and Percent Yield .txt", "text": "Now, let's suppose we react 1 mol of methane with two moles of oxygen, and we find that our actual yield in grams was 38 grams of carbon dioxide."}, {"title": "Theoretical and Percent Yield .txt", "text": "Now, if we find our theoretical yield, we could then find our percent yield."}, {"title": "Theoretical and Percent Yield .txt", "text": "How would we go about finding our theoretical yield?"}, {"title": "Theoretical and Percent Yield .txt", "text": "Well, we have to realize that we have 1 mol reacting in two moles."}, {"title": "Theoretical and Percent Yield .txt", "text": "That means a theoretical yield of this guy is 1 mol."}, {"title": "Theoretical and Percent Yield .txt", "text": "Because one to two gives you one of this guy and two of this guy."}, {"title": "Theoretical and Percent Yield .txt", "text": "And 1 mol of carbon dioxide is simply well, we take our molecular weight of our carbon dioxide which is 12 grams/mol for carbon dioxide and 32 grams/mol for two oxygens and we get 32 plus twelve gives us 44 grams/mol."}, {"title": "Theoretical and Percent Yield .txt", "text": "This is our molecular weight of carbon dioxide."}, {"title": "Theoretical and Percent Yield .txt", "text": "So you multiply by 1 mol and we get the theoretical yield is 44 grams of carbon dioxide."}, {"title": "Theoretical and Percent Yield .txt", "text": "So now we follow our formula."}, {"title": "Theoretical and Percent Yield .txt", "text": "We take our 38 grams our actual yield that we found from the experiment divide that by our 44 grams, our theoretical yield."}, {"title": "Theoretical and Percent Yield .txt", "text": "This guy multiply that by 100% to find a percentage and we find that our percent yield is 86.4%."}, {"title": "Theoretical and Percent Yield .txt", "text": "In other words, this is a pretty good yield because we see that our actual yield is not too far off from our theoretical radical yield."}, {"title": "Theoretical and Percent Yield .txt", "text": "Anything 80% or above is considered to be a good yield."}, {"title": "Introduction to Alkanes .txt", "text": "So in this lecture, I'd like to give a brief introduction to alkanes."}, {"title": "Introduction to Alkanes .txt", "text": "Now, alkanes are a member of a family of hydrocarbons, and that simply means alkanes are composed entirely of carbons and H atoms."}, {"title": "Introduction to Alkanes .txt", "text": "Now, all linear alkanes have the following molecular formula c subscript NH, subscript two N plus two, where N designates the number of carbons."}, {"title": "Introduction to Alkanes .txt", "text": "For example, if N is ten, if we have an alkane composed of ten carbon atoms, that means we're going to have 22 H atoms."}, {"title": "Introduction to Alkanes .txt", "text": "Two times ten plus two is 22."}, {"title": "Introduction to Alkanes .txt", "text": "The simplest alkane is methane."}, {"title": "Introduction to Alkanes .txt", "text": "Methane is composed of one carbon and four hydrogens."}, {"title": "Introduction to Alkanes .txt", "text": "Now, the molecular formula is ch four."}, {"title": "Introduction to Alkanes .txt", "text": "This can be represented another way using the following diagram."}, {"title": "Introduction to Alkanes .txt", "text": "So, the carbon central atom is attached to four identical H atoms in the following manner, where each bond is a covalent bond and each bond is SP three hybridized."}, {"title": "Introduction to Alkanes .txt", "text": "Now, what happens, for example, if we take away this H atom and along with the H atom, we take away one electron and we leave one electron on this molecule."}, {"title": "Introduction to Alkanes .txt", "text": "Now, let's suppose I take two of such molecules and I interact them in such a way so that I form the following compound."}, {"title": "Introduction to Alkanes .txt", "text": "So, these two electrons interact to form a covalent SP three hybridized bond, and I form a compound with two carbons."}, {"title": "Introduction to Alkanes .txt", "text": "So now I have Ethane, which has a molecular formula c, two H six."}, {"title": "Introduction to Alkanes .txt", "text": "Now, I can continue doing this to produce propane, butane pentane, hexane, heptane, octane and so on."}, {"title": "Introduction to Alkanes .txt", "text": "Now, butane for example, is another type of alkane that's composed of four carbon atoms."}, {"title": "Introduction to Alkanes .txt", "text": "So I essentially took four of these molecules, I combined them and I got the following butane molecule."}, {"title": "Introduction to Alkanes .txt", "text": "Now, another type of alkane are cycloalkanes."}, {"title": "Introduction to Alkanes .txt", "text": "These are simply cyclic versions of their alkanes."}, {"title": "Introduction to Alkanes .txt", "text": "And here I have two examples."}, {"title": "Introduction to Alkanes .txt", "text": "For example, cyclopropane and cyclohexane."}, {"title": "Introduction to Alkanes .txt", "text": "So essentially propane, pro means three a refers to the alkane, and cycle means it's in a cyclic fashion."}, {"title": "Introduction to Alkanes .txt", "text": "So here I have cyclopropane and cyclohexane, six carbon atoms and three carbon atoms here."}, {"title": "Introduction to Alkanes .txt", "text": "Now, the formula for cycle alkanes is not the same as the formula for linear alkanes."}, {"title": "Introduction to Alkanes .txt", "text": "The formula for cycloalkanes are CNH, two N. And we can see that this, in fact, is true."}, {"title": "Introduction to Alkanes .txt", "text": "Here we have six H atoms and we have three carbon atoms."}, {"title": "Introduction to Alkanes .txt", "text": "So three carbon atoms, that means we'll have two times three six H atoms."}, {"title": "Introduction to Alkanes .txt", "text": "Likewise, here we have six carbons."}, {"title": "Introduction to Alkanes .txt", "text": "That means we will have twelve H atoms."}, {"title": "Introduction to Alkanes .txt", "text": "That's exactly what we have."}, {"title": "Introduction to Alkanes .txt", "text": "Two, four, 6810, twelve."}, {"title": "Introduction to Alkanes .txt", "text": "So, once again, alkanes and cycle alkanes are essentially entirely composed of H atoms and carbon atoms."}, {"title": "Introduction to Alkanes .txt", "text": "The only difference between alkanes and cycloalkanes is the fact that in the molecular formula we're going to have two N plus two for alkanes and two N for cycloalkanes."}, {"title": "pH Example #2.txt", "text": "So in this example we begin with the blood PH of 7.41."}, {"title": "pH Example #2.txt", "text": "What we want to find is the hydronium concentration of our blood and the hydroxide concentration of our blood."}, {"title": "pH Example #2.txt", "text": "So before we begin a luxury view exponents."}, {"title": "pH Example #2.txt", "text": "Remember exponents is simply another way of writing logs."}, {"title": "pH Example #2.txt", "text": "And logs is simply another way of writing exponents."}, {"title": "pH Example #2.txt", "text": "We can convert from one form to the other whenever it's convenient."}, {"title": "pH Example #2.txt", "text": "For example, let's look at this above statement."}, {"title": "pH Example #2.txt", "text": "Here we have our base is x, our exponent is e and our y is our result."}, {"title": "pH Example #2.txt", "text": "So this guy equals this guy."}, {"title": "pH Example #2.txt", "text": "Now we can convert from this form to the log form."}, {"title": "pH Example #2.txt", "text": "And the logform basically states that our log of our base x in parentheses is our result y and this equals our exponent."}, {"title": "pH Example #2.txt", "text": "So why is this useful?"}, {"title": "pH Example #2.txt", "text": "Well let's see."}, {"title": "pH Example #2.txt", "text": "If we know our base and we know our y, the result and we don't know our e, there's nothing we can do in this form to solve this problem."}, {"title": "pH Example #2.txt", "text": "But what we can do is simply convert this guy to log form and we get log of x, which is what we know."}, {"title": "pH Example #2.txt", "text": "In parentheses is our y, which is also what we know."}, {"title": "pH Example #2.txt", "text": "And we want to find our e. So now we have this entire guy."}, {"title": "pH Example #2.txt", "text": "We don't count this guy."}, {"title": "pH Example #2.txt", "text": "So now what we can do is simply plug this guy to the calculator, get an answer, and that's our e. Now suppose we were in the opposite situation."}, {"title": "pH Example #2.txt", "text": "Suppose we had our log x our base and we had our exponent and we didn't have our y."}, {"title": "pH Example #2.txt", "text": "Well now we don't have this entire thing."}, {"title": "pH Example #2.txt", "text": "So we can plug this into our calculator."}, {"title": "pH Example #2.txt", "text": "What we must do is convert from this guy to the exponent form because we have the base x, we have the y, the e to exponent."}, {"title": "pH Example #2.txt", "text": "Now we have x to the e, plug that into the calculator and we get our y."}, {"title": "pH Example #2.txt", "text": "And this is exactly what we do in part one."}, {"title": "pH Example #2.txt", "text": "So in part one, let's first write down our formula for PH."}, {"title": "pH Example #2.txt", "text": "We know PH is equal to the negative log of our hydronium concentration."}, {"title": "pH Example #2.txt", "text": "But that's the same thing as saying negative log of the hydride ion concentration."}, {"title": "pH Example #2.txt", "text": "So that means this guy equals this guy."}, {"title": "pH Example #2.txt", "text": "And we know from what skewed them that our PH is 7.41."}, {"title": "pH Example #2.txt", "text": "So this guy equals 7.41."}, {"title": "pH Example #2.txt", "text": "So let's go back here for a second."}, {"title": "pH Example #2.txt", "text": "So we have our exponents, we have e, we have our log, which is log ten."}, {"title": "pH Example #2.txt", "text": "We have the ten, we have the x."}, {"title": "pH Example #2.txt", "text": "We don't have our inside, so we don't have our y."}, {"title": "pH Example #2.txt", "text": "So we're in a situation where we can't solve in this form for the y."}, {"title": "pH Example #2.txt", "text": "What we must do is we must convert from this form to the exponent form."}, {"title": "pH Example #2.txt", "text": "So the equivalent way of writing logs and exponents is taking our base, base x, writing it here."}, {"title": "pH Example #2.txt", "text": "Okay then taking our exponents, our exponent and writing it here but wait, we have a negative log."}, {"title": "pH Example #2.txt", "text": "So this negative, we bring it over to here."}, {"title": "pH Example #2.txt", "text": "By simply dividing or multiplying both sides by negative one, this guy cancels becomes a positive."}, {"title": "pH Example #2.txt", "text": "This guy becomes a negative."}, {"title": "pH Example #2.txt", "text": "We get ten to the negative 7.41 is equal."}, {"title": "pH Example #2.txt", "text": "Now we take our calculator, we simply plug it into our calculator and we find our result, namely 3.89 times ten to the negative eight molar."}, {"title": "pH Example #2.txt", "text": "And this is equivalent to this guy and this guy."}, {"title": "pH Example #2.txt", "text": "This is our hydrogen ion concentration as well as our hydronium ion concentration."}, {"title": "pH Example #2.txt", "text": "So we found part one."}, {"title": "pH Example #2.txt", "text": "Let's move on to part two."}, {"title": "pH Example #2.txt", "text": "So, the first step in part two is writing the equation for our dissociation of water."}, {"title": "pH Example #2.txt", "text": "So, water in the liquid states dissociates into two ions, namely H plus ion in the aqueous state and oh minus ion in the aqueous state."}, {"title": "pH Example #2.txt", "text": "Notice that we have 1 mol becomes 1 mol in 1 mol."}, {"title": "pH Example #2.txt", "text": "So now let's write the equilibrium constant equation."}, {"title": "pH Example #2.txt", "text": "So our constant kw, which is what?"}, {"title": "pH Example #2.txt", "text": "We don't know where we could find that in a textbook or online."}, {"title": "pH Example #2.txt", "text": "So this is something we actually know equals concentration of hydroxide times concentration of Hydride."}, {"title": "pH Example #2.txt", "text": "So we know this."}, {"title": "pH Example #2.txt", "text": "This is what we found here upstairs, right?"}, {"title": "pH Example #2.txt", "text": "We don't know this."}, {"title": "pH Example #2.txt", "text": "This is what we want to find."}, {"title": "pH Example #2.txt", "text": "And we know this as well."}, {"title": "pH Example #2.txt", "text": "This, if you look up online at 25 degrees Celsius, is simply 1.0 times ten to the negative 14."}, {"title": "pH Example #2.txt", "text": "And that always holds true."}, {"title": "pH Example #2.txt", "text": "So you should probably remember that."}, {"title": "pH Example #2.txt", "text": "So this guy equals our unknown times what?"}, {"title": "pH Example #2.txt", "text": "These data from part one, 3.89\ntimes ten to negative eight."}, {"title": "pH Example #2.txt", "text": "We bring this guy over here, we solve divide 1.0 times ten to the negative 14 divided by 3.89\ntimes ten to negative eight, we get 2.57 times ten to the negative seven."}, {"title": "pH Example #2.txt", "text": "So this is our concentration of our hydroxide within our blood."}, {"title": "pH Example #2.txt", "text": "So we did part one."}, {"title": "pH Example #2.txt", "text": "We did part two."}, {"title": "pH Example #2.txt", "text": "Part three basically asks us to say if our blood is basic or acidic."}, {"title": "pH Example #2.txt", "text": "Well, this is the easiest part because if it's 7.41 and 7.41 is above seven, anything above seven is basic amount of blood is basic or slightly basic because it's a little bit above seven point."}, {"title": "Ethane.txt", "text": "Now, in this lecture, we're going to build an ethane molecule from two methane molecules."}, {"title": "Ethane.txt", "text": "Now, ethane is an alkane."}, {"title": "Ethane.txt", "text": "It's composed of two carbons and a total of six H atoms."}, {"title": "Ethane.txt", "text": "A methane molecule, however, is the simplest alkane."}, {"title": "Ethane.txt", "text": "It's composed of one carbon and four H atoms, identical H atoms attached to the carbon via SP three hybridized orbitals."}, {"title": "Ethane.txt", "text": "So we're basically going to take two methane molecules, combine them, and form our ethylene."}, {"title": "Ethane.txt", "text": "But before we actually combine them, we have to turn them into methyl radicals."}, {"title": "Ethane.txt", "text": "A methyl radical is simply a methane molecule minus an h atom and an electron."}, {"title": "Ethane.txt", "text": "So to create a methyl radical from a methane molecule, we take away an h atom along with one electron."}, {"title": "Ethane.txt", "text": "But the same thing goes for this second methane molecule."}, {"title": "Ethane.txt", "text": "We take away an h atom along with one electron."}, {"title": "Ethane.txt", "text": "So now we have a methylradical in this radical."}, {"title": "Ethane.txt", "text": "These bonds between the carbon and the H are approximately SP two hybridyne."}, {"title": "Ethane.txt", "text": "And this orbital is approximately a two P orbital."}, {"title": "Ethane.txt", "text": "And our electron, the single electron, will be found within this two p orbital."}, {"title": "Ethane.txt", "text": "The same thing goes for the second methyl radical."}, {"title": "Ethane.txt", "text": "We have SP two hybridized bond between the carbon and H, and we have one electron found within this two p orbital."}, {"title": "Ethane.txt", "text": "Now, when these two methyl radicals begin to approach one another, the lobes, which are approximately two p, become approximately SP three hybridized."}, {"title": "Ethane.txt", "text": "And that simply means that as they approach one another, these green sections become larger and larger, and these blue sections become smaller and smaller."}, {"title": "Ethane.txt", "text": "And eventually, when they come close enough, there is an overlap between these two SP three hybridized orbitals, and they form what we know as a covalent bond."}, {"title": "Ethane.txt", "text": "And we get our ethane molecule, in which every single bond is SP three hybridized."}, {"title": "Ethane.txt", "text": "Once again, to build methane I'm sorry, to build this should be ethane."}, {"title": "Ethane.txt", "text": "To build ethane, we begin with two methyl radicals."}, {"title": "Ethane.txt", "text": "They're orbitals containing the electrons react, forming an SP three sigma bond, as we saw here."}, {"title": "Ethane.txt", "text": "Once again, individually, these methyl roticals contain SP two hybridized bonds with approximately two p orbital that contains our electrons."}, {"title": "Ethane.txt", "text": "But when they come closer, these orbitals become SP three hybridized, which eventually form the bond, forming our ethane molecule."}, {"title": "Ethane.txt", "text": "Now, let's look at our electron diagram or energy diagram for these two bonds."}, {"title": "Ethane.txt", "text": "So here we have our SP three hybridized bond."}, {"title": "Ethane.txt", "text": "They interact."}, {"title": "Ethane.txt", "text": "They each have one electron each."}, {"title": "Ethane.txt", "text": "And then they form two molecular orbitals."}, {"title": "Ethane.txt", "text": "One is a sigma bonding molecular orbital, and the second one is a sigma antibonding molecular orbital."}, {"title": "Ethane.txt", "text": "Now, this guy will be lower in energy."}, {"title": "Ethane.txt", "text": "This guy will be larger."}, {"title": "Ethane.txt", "text": "It will have larger amount of energy."}, {"title": "Ethane.txt", "text": "And that means that our electrons will tend to go into the orbital that is lower in energy."}, {"title": "Ethane.txt", "text": "So our electrons will tend to go into this lower bonding sigma orbital."}, {"title": "Ethane.txt", "text": "And so this guy is lower in energy than both this and this atomic orbital."}, {"title": "Ethane.txt", "text": "So, what is the meaning of this?"}, {"title": "Ethane.txt", "text": "Well, let's look at our reaction."}, {"title": "Ethane.txt", "text": "So, our reaction takes place in the following way."}, {"title": "Ethane.txt", "text": "Our reactants A, which are simply two methyl radicals, react."}, {"title": "Ethane.txt", "text": "They have to surmel this activation barrier."}, {"title": "Ethane.txt", "text": "They reach some transition states down here, and then they drop down and form our product, our essay molecule."}, {"title": "Ethane.txt", "text": "And because this final bond is lower in energy than either of these two atomic orbitals, we release energy and we release our energy."}, {"title": "Ethane.txt", "text": "Change in enthalpy."}, {"title": "Ethane.txt", "text": "So change in energy simply change in enthalpy."}, {"title": "Ethane.txt", "text": "So, as our reaction progresses, our energy drops by this amount, and it's actually 900 kilogows per mole."}, {"title": "Ethane.txt", "text": "In other words, if we have 1 mol of methyl radical reaction with 1 mol of methyl radical, we form 1 mol of essay and we release energy."}, {"title": "Ethane.txt", "text": "So we release 90 energy."}, {"title": "Ethane.txt", "text": "So this is a favorable reaction in terms of our change in enthalpy."}, {"title": "Heat .txt", "text": "Today we're going to talk about energy transfer between one system and a second system or one object and a second object."}, {"title": "Heat .txt", "text": "Energy transfer occurs in two ways, either by heat or by work."}, {"title": "Heat .txt", "text": "Today we're only going to talk about heat."}, {"title": "Heat .txt", "text": "Now, heat is a transfer of energy from a hot object to a cold object."}, {"title": "Heat .txt", "text": "And this occurs naturally or spontaneously."}, {"title": "Heat .txt", "text": "There are three ways by which heat occurs."}, {"title": "Heat .txt", "text": "The first one is conduction."}, {"title": "Heat .txt", "text": "Conduction is energy transfer due to physical contact between the two objects or the two systems."}, {"title": "Heat .txt", "text": "Here I've outlined two situations."}, {"title": "Heat .txt", "text": "In the first situation, I have two blocks of the same size."}, {"title": "Heat .txt", "text": "The first block is at a higher temperature, Th."}, {"title": "Heat .txt", "text": "The second block is at a lower temperature, TL."}, {"title": "Heat .txt", "text": "And nothing is connecting the two objects."}, {"title": "Heat .txt", "text": "No physical barrier, no physical connection occurs here."}, {"title": "Heat .txt", "text": "In situation two, however, I have the same two blocks at the same two temperatures and a solid bridge connecting the two blocks."}, {"title": "Heat .txt", "text": "Okay?"}, {"title": "Heat .txt", "text": "In this situation, conduction will occur because of this metal bridge, and energy will be transferred."}, {"title": "Heat .txt", "text": "Energy flow will occur in this direction."}, {"title": "Heat .txt", "text": "And in this situation, there is no physical bridge that connects the two situations."}, {"title": "Heat .txt", "text": "Yes, there are air molecules flying around in this space here, but there is no solid physical thing that's connecting the two systems, and therefore, conduction will not occur."}, {"title": "Heat .txt", "text": "A visible example of conduction is when a person takes a pencil or a pen or a marker in their hand, holds it tightly for 30 seconds, two minutes, let it go, and notices that the temperature rises in the marker or the pencil."}, {"title": "Heat .txt", "text": "And this occurs because there's an energy transfer or flow of energy from my body, from my hand, from my palm into this marker, thereby raising the temperature of this marker."}, {"title": "Heat .txt", "text": "That is conduction."}, {"title": "Heat .txt", "text": "And it only occurs when there is physical contact."}, {"title": "Heat .txt", "text": "So when people talk about conduction, they usually talk about energy flow or the rate of energy flow within the system."}, {"title": "Heat .txt", "text": "In this situation outlined here, I have a hot system, a cold system, the physical contact, the bridge that's connecting the two systems, okay?"}, {"title": "Heat .txt", "text": "And energy flow will occur, will travel from here to here within this bridge."}, {"title": "Heat .txt", "text": "And the rate of that flow can be given by this equation here."}, {"title": "Heat .txt", "text": "Okay?"}, {"title": "Heat .txt", "text": "So Q over T, where T is the time it takes for it to travel this distance."}, {"title": "Heat .txt", "text": "Q is the flow of heat or flow of energy equals K times A over L times the change in temperature."}, {"title": "Heat .txt", "text": "Okay?"}, {"title": "Heat .txt", "text": "And K here is simply a constant called a thermal connectivity constant that depends on the object or the system used."}, {"title": "Heat .txt", "text": "And it differs from one object to the second object."}, {"title": "Heat .txt", "text": "It basically depends on the composition of the object."}, {"title": "Heat .txt", "text": "It also depends slightly on the temperature of the object being used."}, {"title": "Heat .txt", "text": "Okay, l here is the distance, the distance from this object to the second object."}, {"title": "Heat .txt", "text": "Therefore, the entire bridge distance l would be plugged in here okay?"}, {"title": "Heat .txt", "text": "Now, the area isn't the area of this."}, {"title": "Heat .txt", "text": "It isn't the area of this."}, {"title": "Heat .txt", "text": "It's the area of the bridge that's connecting it's the area of the face side."}, {"title": "Heat .txt", "text": "The face side is this side."}, {"title": "Heat .txt", "text": "If you take this out, this is the area we want, okay?"}, {"title": "Heat .txt", "text": "And this is the length that we're talking about here."}, {"title": "Heat .txt", "text": "Now, the difference in temperature is simply this temperature minus this temperature, when you plot the things in, you get the rate of heat flow, okay?"}, {"title": "Heat .txt", "text": "And this will become important only when you're dealing with conduction and nothing else."}, {"title": "Heat .txt", "text": "This formula only applies for conduction."}, {"title": "Heat .txt", "text": "The second way by which energy is transferred due to heat is called convection."}, {"title": "Heat .txt", "text": "Convection is a transfer of energy due to the movement of fluids."}, {"title": "Heat .txt", "text": "And fluids can both include gas and liquid, okay?"}, {"title": "Heat .txt", "text": "And convection absolutely requires the presence of molecules or atoms within the medium."}, {"title": "Heat .txt", "text": "There is no longer a need for a physical presence or a physical bridge connecting two objects or two systems, but there is a need for those molecules, okay?"}, {"title": "Heat .txt", "text": "And here we have a common example used to describe or convey convection, okay?"}, {"title": "Heat .txt", "text": "Here we have a cup of coffee."}, {"title": "Heat .txt", "text": "You know that if you leave a cup of coffee, as in temperature, eventually it will cool down."}, {"title": "Heat .txt", "text": "That's because energy transferred from the cup of coffee to the air, okay?"}, {"title": "Heat .txt", "text": "What actually happens on a microscopic level is that the atoms, for example, diatomic oxygen, hit the surface of the water, okay?"}, {"title": "Heat .txt", "text": "When they hit the surface of the water, they bounce back with a higher kinetic energy, okay?"}, {"title": "Heat .txt", "text": "So the oxygen gain kinetic energy while this lost kinetic energy, so it lost the heat."}, {"title": "Heat .txt", "text": "It lost energy because of conservation of energy, okay?"}, {"title": "Heat .txt", "text": "Eventually, enough of these atoms will attack or hit the surface of the water that it will lose most of its energy, and this will cool it down, okay?"}, {"title": "Heat .txt", "text": "And that's why convection can only occur in the presence of molecules."}, {"title": "Heat .txt", "text": "And conduction requires physical contact."}, {"title": "Heat .txt", "text": "The third and final type of energy transfer that occurs due to heat is called radiation."}, {"title": "Heat .txt", "text": "Radiation is the energy transfer that occurs due to the presence of electromagnetic waves, okay?"}, {"title": "Heat .txt", "text": "These electromagnetic waves can include UV waves, radio waves, microwaves and infrared waves, and other waves as well."}, {"title": "Heat .txt", "text": "So all objects on Earth and in space radiate heat or radiate energy."}, {"title": "Heat .txt", "text": "And that's because every single object has some temperature and zero Kelvin, the absolute zero temperature, is unattainable."}, {"title": "Heat .txt", "text": "So all objects vibrate or move to a certain extent, and therefore all objects at all times radiate energy."}, {"title": "Heat .txt", "text": "Okay?"}, {"title": "Heat .txt", "text": "One cool thing about radiation, unlike convection or conduction, is that radiation can occur in the absence of molecules or in the absence of a physical barrier."}, {"title": "Heat .txt", "text": "And this is seen in space when light travels from the sun, the hot object to the Earth, the cooler object, the waves travel in a vacuum in the absence of molecules."}, {"title": "Heat .txt", "text": "And that's because waves, electromagnetic waves, are actually energy bundles that carry themselves from a hot object to a cool object, okay?"}, {"title": "Heat .txt", "text": "And it is radiation that heats the Earth."}, {"title": "Heat .txt", "text": "When we spoke earlier about conduction, we also mentioned rate of energy transfer."}, {"title": "Heat .txt", "text": "Here we can also talk about a similar concept, rate of energy transfer."}, {"title": "Heat .txt", "text": "But the formula here, it's different."}, {"title": "Heat .txt", "text": "The formula here is power, which is actually change in energy over time, which is a rate flow is equal to sigma, which is a constant and will be given to you admissitivity value A and T. T is the temperature of the object."}, {"title": "Heat .txt", "text": "A is the area of the face that's radiating the heat, and this is a value between zero and one."}, {"title": "Heat .txt", "text": "Now, where this value is one, that that simply means that the object is absorbing all the heat, is absorbing all the radiation, which means that it also releases all the radiation, okay?"}, {"title": "Heat .txt", "text": "Now, a black body object is an object that has this value that equals one."}, {"title": "Heat .txt", "text": "Now, technically, such an object does not exist, and that's because if such an object did exist, it would not reflect any of the waves and would not reflect light waves, and so we would not be able to see it."}, {"title": "Heat .txt", "text": "It would be invisible to us."}, {"title": "Heat .txt", "text": "So technically, it does not exist because every single object to some degree is visible to us, okay?"}, {"title": "Heat .txt", "text": "And a value of zero simply means that it reflects all the radiation, doesn't absorb any radiation, so it doesn't release any radiation, okay?"}, {"title": "Electronegativity and Polar Bonds.txt", "text": "So what exactly is electronegativity?"}, {"title": "Electronegativity and Polar Bonds.txt", "text": "Well, electronegativity is usually defined as the ability of atoms to attract electrons."}, {"title": "Electronegativity and Polar Bonds.txt", "text": "In other words, how likely is it that the protons found in the nucleus will attract our electrons in the atom?"}, {"title": "Electronegativity and Polar Bonds.txt", "text": "So we know as electronegativity increases."}, {"title": "Electronegativity and Polar Bonds.txt", "text": "According to our definition, the atoms ability to attract electrons also increases."}, {"title": "Electronegativity and Polar Bonds.txt", "text": "And generally speaking, according to our periodic trends, as we go up a group or across a period from left to right on our periodic table, the electrodegativity of the atoms increases."}, {"title": "Electronegativity and Polar Bonds.txt", "text": "In other words, their ability to attract electrons increases."}, {"title": "Electronegativity and Polar Bonds.txt", "text": "So, for example, let's take the second period."}, {"title": "Electronegativity and Polar Bonds.txt", "text": "As we go from Lithium to Beryllium all the way to fluorine."}, {"title": "Electronegativity and Polar Bonds.txt", "text": "The electronegativity of these atoms increases."}, {"title": "Electronegativity and Polar Bonds.txt", "text": "And in fact, fluorine and oxygen are the two most electronegative atoms found on our periodic table."}, {"title": "Electronegativity and Polar Bonds.txt", "text": "So we just defined what electronegativity is."}, {"title": "Electronegativity and Polar Bonds.txt", "text": "But where does it come from?"}, {"title": "Electronegativity and Polar Bonds.txt", "text": "What determines electronegativity well, it turns out another important principle known as effective nuclear charge determines or creates electronegativity."}, {"title": "Electronegativity and Polar Bonds.txt", "text": "Now effective nuclear charge is simply the charge that the balanced electrons found in the outermost shell feel due to the protons found in the nucleus."}, {"title": "Electronegativity and Polar Bonds.txt", "text": "Remember, electrons and protons attract one another."}, {"title": "Electronegativity and Polar Bonds.txt", "text": "Now, normally, the effective nuclear charge is smaller than the actual nuclear charge found in the nucleus."}, {"title": "Electronegativity and Polar Bonds.txt", "text": "And that's because some of the electrons found in the innermost shell shield the charge."}, {"title": "Electronegativity and Polar Bonds.txt", "text": "They decrease the charge, creating a shielding effect."}, {"title": "Electronegativity and Polar Bonds.txt", "text": "So, in other words, the more balanced electrons we have, the more our nuclear charge is."}, {"title": "Electronegativity and Polar Bonds.txt", "text": "Effective nuclear charge."}, {"title": "Electronegativity and Polar Bonds.txt", "text": "The more inner most electrons we have in the innermost shell, the smaller our effective nuclear charge."}, {"title": "Electronegativity and Polar Bonds.txt", "text": "So once again, electronegativity arises from effective nuclear charge."}, {"title": "Electronegativity and Polar Bonds.txt", "text": "The more dense electrons an atom has, the larger the effective nuclear charge is, the more electronegative the atom."}, {"title": "Electronegativity and Polar Bonds.txt", "text": "And that's exactly why electronegativity increases as we go from lithium to fluorine."}, {"title": "Electronegativity and Polar Bonds.txt", "text": "Because the number of bounced electrons found in each atom increases as we go from left to right on our periodic table."}, {"title": "Electronegativity and Polar Bonds.txt", "text": "Also the ratio of bounce electrons to the innermost electrons also increases."}, {"title": "Electronegativity and Polar Bonds.txt", "text": "So let's take lithium, for example, and let's compare it to fluorine."}, {"title": "Electronegativity and Polar Bonds.txt", "text": "So Lithium has one bounced electron in the two S shell, while this fluorine has seven bounced electrons."}, {"title": "Electronegativity and Polar Bonds.txt", "text": "So because this has more balanced electrons and because the ratio is seven to two versus one to two, because the ratio here is much larger, this has much more effective nuclear charge and therefore it's more electronegative."}, {"title": "Electronegativity and Polar Bonds.txt", "text": "So electronegativity in polar bonds go hand in hand."}, {"title": "Electronegativity and Polar Bonds.txt", "text": "In fact, polar bonds or polar codalent bonds are formed because of differences in electronegativity."}, {"title": "Electronegativity and Polar Bonds.txt", "text": "Once again, polar bonds are created due to electronegativity differences between the atoms composing the bond."}, {"title": "Electronegativity and Polar Bonds.txt", "text": "So, as an example, let's look at HF."}, {"title": "Electronegativity and Polar Bonds.txt", "text": "So h donates one electron and the fluorine also donates one electron."}, {"title": "Electronegativity and Polar Bonds.txt", "text": "But because this fluorine atom is more electronegative, it attracts electrons more strongly."}, {"title": "Electronegativity and Polar Bonds.txt", "text": "That means that electron density will be closer."}, {"title": "Electronegativity and Polar Bonds.txt", "text": "The electrons will be closer to our fluorine."}, {"title": "Electronegativity and Polar Bonds.txt", "text": "And for the fluorine will develop a partial negative charge."}, {"title": "Electronegativity and Polar Bonds.txt", "text": "While this h will develop a partial positive charge."}, {"title": "Electronegativity and Polar Bonds.txt", "text": "The electrons will not be shared equally."}, {"title": "Electronegativity and Polar Bonds.txt", "text": "They're going to be closer to the fluorine."}, {"title": "Electronegativity and Polar Bonds.txt", "text": "So if we examine the molecular orbital of this bond, we see that the one s orbital combines overlaps with the SP three orbital of the fluorine forming this hybridized or this molecular orbital."}, {"title": "Electronegativity and Polar Bonds.txt", "text": "And the electrons found in this molecular orbital will be closer to the fluorine nucleus than the h nucleus."}, {"title": "Electronegativity and Polar Bonds.txt", "text": "And once again, that's why we have a partial negative on the fluorine and a partial positive on the h.\nSo recall that Bronsted larry acids are compounds that donate an h ion."}, {"title": "Electronegativity and Polar Bonds.txt", "text": "So, for example, this hydrofluoric acid is a Bronxed larry acid because it has an H that it can donate."}, {"title": "Electronegativity and Polar Bonds.txt", "text": "So what determines if a compound is a good Bronsted larry acid?"}, {"title": "Electronegativity and Polar Bonds.txt", "text": "So, good Bronsted larry acids have very polar bonds, which means that the h atoms are held very weakly and therefore are donated very readily."}, {"title": "Electronegativity and Polar Bonds.txt", "text": "So this polar bond is very polar, and that's because we have a very electronegative atom and not so electronegative atom."}, {"title": "Electronegativity and Polar Bonds.txt", "text": "So there is a large difference in electronegativity creating a very polar bond."}, {"title": "Electronegativity and Polar Bonds.txt", "text": "And so the bond will be weak."}, {"title": "Electronegativity and Polar Bonds.txt", "text": "This h will be held very weakly because electrons will be closer to the fluorine, and so it will readily dissociate in water to produce an h ion with a plus one charge and an fion with a minus one charge."}, {"title": "Chalcogen\u2019s and Noble Gases .txt", "text": "In this lecture, we're going to talk about two more groups or families found on our Fiana table known as the calculus, or group 16, six A, and the noble gas group, or group 18 or eight A."}, {"title": "Chalcogen\u2019s and Noble Gases .txt", "text": "Now, let's begin with our calculations."}, {"title": "Chalcogen\u2019s and Noble Gases .txt", "text": "Now, there are five main calculations."}, {"title": "Chalcogen\u2019s and Noble Gases .txt", "text": "Oxygen, sulfur and selenium are all nonmetals, while our metalloids are polonium and talorium."}, {"title": "Chalcogen\u2019s and Noble Gases .txt", "text": "Now notice, unlike group five A and four A, which both have metals, group six A, or the calcigens, don't have any metals."}, {"title": "Chalcogen\u2019s and Noble Gases .txt", "text": "Now, let's begin with oxygen."}, {"title": "Chalcogen\u2019s and Noble Gases .txt", "text": "Now, in this lecture, we're only really going to look at oxygen and sulfur because they occur way more frequently than any of these three guys."}, {"title": "Chalcogen\u2019s and Noble Gases .txt", "text": "So let's look at oxygen."}, {"title": "Chalcogen\u2019s and Noble Gases .txt", "text": "Oxygen is the second most electronegative atom."}, {"title": "Chalcogen\u2019s and Noble Gases .txt", "text": "In other words, it likes to take electrons."}, {"title": "Chalcogen\u2019s and Noble Gases .txt", "text": "Now, we'll talk more about electronegativity in a future lecture."}, {"title": "Chalcogen\u2019s and Noble Gases .txt", "text": "For now, it's sufficient to say that oxygen is the second most electronegative."}, {"title": "Chalcogen\u2019s and Noble Gases .txt", "text": "It's second to fluorine."}, {"title": "Chalcogen\u2019s and Noble Gases .txt", "text": "And we'll talk more about fluorine when we'll talk about the seven A group elements or the halogens."}, {"title": "Chalcogen\u2019s and Noble Gases .txt", "text": "Now, oxygen, like carbon, also forms strong bonds, strong double bonds."}, {"title": "Chalcogen\u2019s and Noble Gases .txt", "text": "And oxygen exists in nature in a diatomic or a triathlonic form, namely ozone or O two oxygen."}, {"title": "Chalcogen\u2019s and Noble Gases .txt", "text": "Now, O two, or oxygen, reacts with metals, alkaline metals and earth metals and transition metals to form metal oxides."}, {"title": "Chalcogen\u2019s and Noble Gases .txt", "text": "Now, whenever our alkaline metals react with our oxygen, they form peroxide, for example, li two or ma two, et cetera."}, {"title": "Chalcogen\u2019s and Noble Gases .txt", "text": "Now let's look at sulphur."}, {"title": "Chalcogen\u2019s and Noble Gases .txt", "text": "Now, sulphur can form two, three, four or even six covalent bonds with other atoms or molecules, and also like oxygen, can form strong pi bonds, namely the double bond."}, {"title": "Chalcogen\u2019s and Noble Gases .txt", "text": "So now let's look at our noble gases."}, {"title": "Chalcogen\u2019s and Noble Gases .txt", "text": "Noble gases are group 18 or eight eight, and they're also known as the inner gases."}, {"title": "Chalcogen\u2019s and Noble Gases .txt", "text": "Now, these guys are extremely stable and therefore, they're very unreactive."}, {"title": "Chalcogen\u2019s and Noble Gases .txt", "text": "And they exist unlike every other atom or most other atoms."}, {"title": "Chalcogen\u2019s and Noble Gases .txt", "text": "For example, oxygen and nitrogen and hydrogen."}, {"title": "Chalcogen\u2019s and Noble Gases .txt", "text": "These guys exist in monotonic gas form at room temperature."}, {"title": "Bomb Calorimeter Example.txt", "text": "In this example, we are given 3.5 grams of glucose, 800 grams of water, an initial temperature of 22 degrees Celsius, a final temperature of 33 degrees Celsius."}, {"title": "Bomb Calorimeter Example.txt", "text": "The heat capacity of our bomb is 840 joules per Celsius."}, {"title": "Bomb Calorimeter Example.txt", "text": "And our specific heat capacity for water is 4.18 joules per Celsius times ground."}, {"title": "Bomb Calorimeter Example.txt", "text": "We want to find the final changes, the energy of our surroundings when 1 mol of glucose is combusted."}, {"title": "Bomb Calorimeter Example.txt", "text": "So let's visualize the example."}, {"title": "Bomb Calorimeter Example.txt", "text": "So here's our bomb kilometer, and we're basically taking the red oxygen molecules and the purple glucose molecules."}, {"title": "Bomb Calorimeter Example.txt", "text": "We're mixing them, combusting them in our bomb or steel bomb."}, {"title": "Bomb Calorimeter Example.txt", "text": "And we want to find the amount of energy released that goes into heating the bomb, and then the amount of energy released that goes into heating the water."}, {"title": "Bomb Calorimeter Example.txt", "text": "So you have to find two things energy that goes into the bomb and the energy that goes into the water."}, {"title": "Bomb Calorimeter Example.txt", "text": "Okay, first, let's look at the equation at hand."}, {"title": "Bomb Calorimeter Example.txt", "text": "So we have 1 mol of glucose and six mole of oxygen combusting into six moles of carbon dioxide and six moles of water."}, {"title": "Bomb Calorimeter Example.txt", "text": "Okay?"}, {"title": "Bomb Calorimeter Example.txt", "text": "So our second step in our second step, we want to find the change in energy that goes from the system, from these two guys, from our glucose and oxygen into our bomb."}, {"title": "Bomb Calorimeter Example.txt", "text": "Okay?"}, {"title": "Bomb Calorimeter Example.txt", "text": "Now remember, our bomb is given a heat capacity of 840 joules per Celsius."}, {"title": "Bomb Calorimeter Example.txt", "text": "So we simply use the formula for heat capacity or Q equals C times change in T. And we present this Q as Q one."}, {"title": "Bomb Calorimeter Example.txt", "text": "And we find that 840 Joules per Celsius times the change in our temperature, or eleven degrees Celsius, gives us 9240 joules."}, {"title": "Bomb Calorimeter Example.txt", "text": "So this million Joules goes from the system into the bomb, into heating the bomb."}, {"title": "Bomb Calorimeter Example.txt", "text": "Now let's calculate that there are the change in energy that goes from the system to our water."}, {"title": "Bomb Calorimeter Example.txt", "text": "Okay?"}, {"title": "Bomb Calorimeter Example.txt", "text": "And we're given a specific heat of water, 4.8\njoules per Celsius times gram."}, {"title": "Bomb Calorimeter Example.txt", "text": "So we have to use this formula because we're using little C. So we let this change down GB, Q Two."}, {"title": "Bomb Calorimeter Example.txt", "text": "We basically plug in our Master of Water, 800 grams times 4.8 joules per gram times Celsius times our difference in temperature."}, {"title": "Bomb Calorimeter Example.txt", "text": "So eleven degrees Celsius, and we get 36,784 joules."}, {"title": "Bomb Calorimeter Example.txt", "text": "So this main joules goes into heating the water, increasing temperature of water by eleven degrees."}, {"title": "Bomb Calorimeter Example.txt", "text": "Okay, the final step is basically to add up the two energies."}, {"title": "Bomb Calorimeter Example.txt", "text": "Because energy in both cases is released, you must add them up."}, {"title": "Bomb Calorimeter Example.txt", "text": "So 9240 plus 36,784 joules gives you 46,024 joules."}, {"title": "Bomb Calorimeter Example.txt", "text": "But there's one last thing left to do."}, {"title": "Bomb Calorimeter Example.txt", "text": "Notice that this amount of Joules corresponds to 3.5\ngrams of glucose, and this amount is much less than 1 mol of glucose."}, {"title": "Bomb Calorimeter Example.txt", "text": "Okay?"}, {"title": "Bomb Calorimeter Example.txt", "text": "So let's see how many moles 3.5 grams of glucose actually corresponds to."}, {"title": "Bomb Calorimeter Example.txt", "text": "So we take our grams, 3.5 grams, divide that by our molecular formula for glucose, which is 180 grams/mol, and we get zero point 19 moles."}, {"title": "Bomb Calorimeter Example.txt", "text": "So this number corresponds to only zero point 19 moles."}, {"title": "Bomb Calorimeter Example.txt", "text": "We want to find how many joules corresponds to 1 mol of glucose."}, {"title": "Bomb Calorimeter Example.txt", "text": "Okay?"}, {"title": "Bomb Calorimeter Example.txt", "text": "So we basically take our number and divide that by our moles, and that gives us 2,422,316 joules per mole."}, {"title": "Bomb Calorimeter Example.txt", "text": "So this number is the amount per mole of glucose."}, {"title": "Bomb Calorimeter Example.txt", "text": "So that's how much energy is released."}, {"title": "Bomb Calorimeter Example.txt", "text": "And because it's released, this means it's negative."}, {"title": "Bomb Calorimeter Example.txt", "text": "So it's negative this number."}, {"title": "Empirical and Molecular Formula .txt", "text": "Whenever an element combines with a second element, it forms something called a compound."}, {"title": "Empirical and Molecular Formula .txt", "text": "Now, in any pure compound, the relative amount of one atom to the second atom can be given or represented using a ratio of whole numbers."}, {"title": "Empirical and Molecular Formula .txt", "text": "For example, let's look at a water molecule."}, {"title": "Empirical and Molecular Formula .txt", "text": "The formula for water is H 20."}, {"title": "Empirical and Molecular Formula .txt", "text": "And the ratio of atom our H molecules to our water molecules is two to one."}, {"title": "Empirical and Molecular Formula .txt", "text": "In other words, for every O molecule, there are two H molecules."}, {"title": "Empirical and Molecular Formula .txt", "text": "Now, this above ratio is known as the empirical formula."}, {"title": "Empirical and Molecular Formula .txt", "text": "Now, on the contrary, there's also something called the molecular formula."}, {"title": "Empirical and Molecular Formula .txt", "text": "And the molecular formula gives you the exact number of atoms found in each compound."}, {"title": "Empirical and Molecular Formula .txt", "text": "Now, sometimes your empirical formula will be the same as your molecular formula."}, {"title": "Empirical and Molecular Formula .txt", "text": "As is in the case of water."}, {"title": "Empirical and Molecular Formula .txt", "text": "This is both an empirical formula and the molecular formula."}, {"title": "Empirical and Molecular Formula .txt", "text": "Other times, these two guys will differ."}, {"title": "Empirical and Molecular Formula .txt", "text": "For example, suppose we look at the hydrocarbon ch 16."}, {"title": "Empirical and Molecular Formula .txt", "text": "The molecular formula gives you the exact amount of atoms."}, {"title": "Empirical and Molecular Formula .txt", "text": "In other words, this is our molecular formula."}, {"title": "Empirical and Molecular Formula .txt", "text": "In this hydrocarbon, there are eight C molecules, carbon molecules and 16 H molecules."}, {"title": "Empirical and Molecular Formula .txt", "text": "However, the empirical formula for this molecule is C one, H two."}, {"title": "Empirical and Molecular Formula .txt", "text": "In other words, for every two H molecules, there is one C molecule."}, {"title": "Empirical and Molecular Formula .txt", "text": "And if we divide 16 by eight, we also get two the same way we divide two by one."}, {"title": "Empirical and Molecular Formula .txt", "text": "So the way you basically go from a molecular to an empirical formula is you find a common number and you divide it by that common number, making sure that we get whole numbers."}, {"title": "Empirical and Molecular Formula .txt", "text": "So in this case, eight goes into 16 twice and eight goes into eight once."}, {"title": "Empirical and Molecular Formula .txt", "text": "Now, why is an empirical formula useful?"}, {"title": "Empirical and Molecular Formula .txt", "text": "Well, an empirical formula can be used to find the percent by mass of any atom in our compound."}, {"title": "Empirical and Molecular Formula .txt", "text": "Now, let's look at this example again."}, {"title": "Empirical and Molecular Formula .txt", "text": "How can we find the percent by mass of hydrogen in our molecule in our compound?"}, {"title": "Empirical and Molecular Formula .txt", "text": "Well, what we do is we take our atomic weight of our H, which is 1 gram/mol and divide that by our molecular weight of this guy or the empirical weight of this guy."}, {"title": "Empirical and Molecular Formula .txt", "text": "And what we get is 14 grams/mol."}, {"title": "Empirical and Molecular Formula .txt", "text": "These guys, these units cancel, and we get one over 14, which is 0.7\n114."}, {"title": "Empirical and Molecular Formula .txt", "text": "Now, to get the percent, we multiply by 100 and we get 7.14% by mass of H in ch two."}, {"title": "Empirical and Molecular Formula .txt", "text": "So in this context, our H takes up 7.14% by mass."}, {"title": "Empirical and Molecular Formula .txt", "text": "So now, suppose I want to find my empirical formula given percent by mass."}, {"title": "Empirical and Molecular Formula .txt", "text": "So suppose I'm given that my compound is eleven point 11% hydrogen and 88.89% oxygen."}, {"title": "Empirical and Molecular Formula .txt", "text": "I have to follow three steps to find the empirical formula."}, {"title": "Empirical and Molecular Formula .txt", "text": "In my first step, I make the assumption that I have 100 grams of my compound."}, {"title": "Empirical and Molecular Formula .txt", "text": "And what I do is I convert this guy to fraction and this guy to fraction by dividing each guy by 100."}, {"title": "Empirical and Molecular Formula .txt", "text": "And then I multiply each guy by my 100 grams of compound to find how many grams of each is in my compound."}, {"title": "Empirical and Molecular Formula .txt", "text": "So, 100 grams of my compound multiplied by 0.111 which I got this guy divided by 100 equals eleven point 11 grams of h in my 100 grams of compound."}, {"title": "Empirical and Molecular Formula .txt", "text": "Now, likewise, I multiply 100 grams times 0.8\n889."}, {"title": "Empirical and Molecular Formula .txt", "text": "This gives me 88.89 grams of oxygen in my 100 grams of compound."}, {"title": "Empirical and Molecular Formula .txt", "text": "Now I have to convert my grams to moles."}, {"title": "Empirical and Molecular Formula .txt", "text": "In other words, I want to find how many moles of each guy of each atom is in my compound."}, {"title": "Empirical and Molecular Formula .txt", "text": "Now, eleven point 11 grams of h divided by the molecular or atomic weight of h 1 gram/mol gives me eleven point eleven moles of h.\nLikewise, I do the same thing for oxygen."}, {"title": "Empirical and Molecular Formula .txt", "text": "88.89 grams of oxygen divided by the atomic weight for oxygen 16 grams/mol grams cancel and I get 5.56\nmole."}, {"title": "Empirical and Molecular Formula .txt", "text": "Now, I simply take this guy, the moles of my h, divide that by the moles of my oxygen and I get two, or approximately two."}, {"title": "Empirical and Molecular Formula .txt", "text": "And this and this means that for every two moles of h, I have 1 mol of oxygen."}, {"title": "Empirical and Molecular Formula .txt", "text": "And therefore, I could write my empirical formula in the following way."}, {"title": "Empirical and Molecular Formula .txt", "text": "For every two moles of h, I have 1 mol of oxygen and my empirical formula is water."}, {"title": "Bomb Calorimeter .txt", "text": "In this lecture we're going to talk about bomb caluminas."}, {"title": "Bomb Calorimeter .txt", "text": "So a bomb killer eminem measures change in energy of the reaction when at least one of the reactants is a gas."}, {"title": "Bomb Calorimeter .txt", "text": "And when we talk about gases, we need to remember that gases compress and expand."}, {"title": "Bomb Calorimeter .txt", "text": "So what Bond kilometers do is they intentionally keep the volume constant by letting the reaction occur in a steel container, in a steel cylinder."}, {"title": "Bomb Calorimeter .txt", "text": "So no expansion in the steel cylinder occurs."}, {"title": "Bomb Calorimeter .txt", "text": "So let's compare box perimeters to coffee cup calorimeters."}, {"title": "Bomb Calorimeter .txt", "text": "In a coffee cup, caliber, expansion or compression was not a problem."}, {"title": "Bomb Calorimeter .txt", "text": "And that's because our reactants were liquids and solids."}, {"title": "Bomb Calorimeter .txt", "text": "Now, liquids and solids don't compress."}, {"title": "Bomb Calorimeter .txt", "text": "And so when we speak about coffee cup kilometers, we talk about constant pressure."}, {"title": "Bomb Calorimeter .txt", "text": "In a Bond kilometer, we talk about constant volume and pressure is allowed to change."}, {"title": "Bomb Calorimeter .txt", "text": "So let's look at the structure of a bomb kilometer."}, {"title": "Bomb Calorimeter .txt", "text": "Now, bomb calorimeters are composed of two cylinders, a large one and a small one."}, {"title": "Bomb Calorimeter .txt", "text": "The outer one is called the insulated chamber and it insulates the entire system."}, {"title": "Bomb Calorimeter .txt", "text": "So energy is not allowed to leave our bomb kilometer."}, {"title": "Bomb Calorimeter .txt", "text": "The intermodal chamber is called a steel bomb and it's basically the location of our reaction."}, {"title": "Bomb Calorimeter .txt", "text": "This is where our reaction occurs and it's made from steel so that the gas can't expand our system."}, {"title": "Bomb Calorimeter .txt", "text": "Now this thermometer is placed into the water and everything is sealed off."}, {"title": "Bomb Calorimeter .txt", "text": "And our goal is to basically change or measure the change in temperature of our reaction, okay?"}, {"title": "Bomb Calorimeter .txt", "text": "The same way we do in a coffee cup calorimeter."}, {"title": "Bomb Calorimeter .txt", "text": "So let's look at this section here."}, {"title": "Bomb Calorimeter .txt", "text": "A sample of a known mass is added to a dish."}, {"title": "Bomb Calorimeter .txt", "text": "So let's look at the combustion of glucose in the presence of oxygen."}, {"title": "Bomb Calorimeter .txt", "text": "Plus some heat gives us carbon dioxide and water."}, {"title": "Bomb Calorimeter .txt", "text": "So let's place a small sample of glucose into our dish found inside the steel bomb and let's fill our bomb with oxygen, right, because oxygen is required for burning to occur."}, {"title": "Bomb Calorimeter .txt", "text": "Next, let's place the steel bomb into a waterfilled the cylinder and let's seal off the top."}, {"title": "Bomb Calorimeter .txt", "text": "Let's place a thermometer inside this section."}, {"title": "Bomb Calorimeter .txt", "text": "Okay?"}, {"title": "Bomb Calorimeter .txt", "text": "Now let's ignite the sample using some electrical spark and this will allow this reaction to occur."}, {"title": "Bomb Calorimeter .txt", "text": "Now, when this reaction begins occurring, carbon dioxide is produced, so more gas produced."}, {"title": "Bomb Calorimeter .txt", "text": "So this system, the pressure increases."}, {"title": "Bomb Calorimeter .txt", "text": "And increase in pressure means there is an increase in temperature when the volume is held constant."}, {"title": "Bomb Calorimeter .txt", "text": "And the increase in temperature will transfer energy from this section to the surroundings, to the water."}, {"title": "Bomb Calorimeter .txt", "text": "And you could measure the change in temperature using this thermometer."}, {"title": "Bomb Calorimeter .txt", "text": "So the initial and final temperature, just like you would in a coffee cup kilometer."}, {"title": "Bomb Calorimeter .txt", "text": "So finally, you can use the change in temperature and the formula to calculate our energy change."}, {"title": "Bomb Calorimeter .txt", "text": "Now let's look at our first law of thermodynamics which states that change in energy is equal to heat plus work."}, {"title": "Bomb Calorimeter .txt", "text": "Now, in this case, no mechanical work is done and no PV work is done because change in volume is zero."}, {"title": "Bomb Calorimeter .txt", "text": "So changed energy is simply the heat or Change in Internal Energy Guard system."}, {"title": "Bomb Calorimeter .txt", "text": "So what we simply do is we simply use this formula by using the total maps plus the specific heat capacity plus change in energy or, I'm sorry, change in temperature, and we could find our change in energy."}, {"title": "Coffee Cup Calorimeter Example .txt", "text": "In this equation, we are given 250 MLS of one molar sodium hydroxide and 250 MLS of one molar hydrochloric acid."}, {"title": "Coffee Cup Calorimeter Example .txt", "text": "Both guys are at one ATM."}, {"title": "Coffee Cup Calorimeter Example .txt", "text": "That means constant pressure."}, {"title": "Coffee Cup Calorimeter Example .txt", "text": "So we have to use a coffee cup calorimeter."}, {"title": "Coffee Cup Calorimeter Example .txt", "text": "Now, we are also given a T initial of 23 degrees Celsius and a T final of 31 one degree Celsius."}, {"title": "Coffee Cup Calorimeter Example .txt", "text": "Our specific heat capacity for both guys is 4.18\njoules per gram times Celsius."}, {"title": "Coffee Cup Calorimeter Example .txt", "text": "We want to find our goal is to find the change in enthalpy or change in energy of our solution."}, {"title": "Coffee Cup Calorimeter Example .txt", "text": "So we take our coffee cup calorimeter, we mix the two different types of compounds."}, {"title": "Coffee Cup Calorimeter Example .txt", "text": "We wait a little."}, {"title": "Coffee Cup Calorimeter Example .txt", "text": "We wait for the observed change in temperature to occur, and we have to calculate the change in energy that corresponds to that change in temperature."}, {"title": "Coffee Cup Calorimeter Example .txt", "text": "So our first step is to see exactly what's going on within our coffee cup calorimeter."}, {"title": "Coffee Cup Calorimeter Example .txt", "text": "So we're basically mixing 1 mol of sodium hydroxide and 1 mol of hydrochloric acid."}, {"title": "Coffee Cup Calorimeter Example .txt", "text": "We get dissociated ions, 1 mol of each."}, {"title": "Coffee Cup Calorimeter Example .txt", "text": "And then these guys, we combine to form 1 mol of salt and 1 mol of water."}, {"title": "Coffee Cup Calorimeter Example .txt", "text": "So our second step and third step involves finding the total grams of our mixture."}, {"title": "Coffee Cup Calorimeter Example .txt", "text": "So you want to find the grams of sodium hydroxide and the grams of hydrochloric acid."}, {"title": "Coffee Cup Calorimeter Example .txt", "text": "This will become important in using this equation."}, {"title": "Coffee Cup Calorimeter Example .txt", "text": "So, this M corresponds to the total mass."}, {"title": "Coffee Cup Calorimeter Example .txt", "text": "That's why we need to find the total mass."}, {"title": "Coffee Cup Calorimeter Example .txt", "text": "So first, before we find the grams of sodium hydroxide, we have to find the moles of sodium hydroxide."}, {"title": "Coffee Cup Calorimeter Example .txt", "text": "To find the moles, we have to take our one molar solution of sodium hydroxide."}, {"title": "Coffee Cup Calorimeter Example .txt", "text": "We multiply that by our volume in liters."}, {"title": "Coffee Cup Calorimeter Example .txt", "text": "So, multiplied by zero point 250 liters, and we get zero point 25 moles of sodium hydroxide."}, {"title": "Coffee Cup Calorimeter Example .txt", "text": "Because the liters cancel, the second step is to find the grams of sodium hydroxide."}, {"title": "Coffee Cup Calorimeter Example .txt", "text": "To find the grams, we must first find the molecular weight of sodium hydroxide."}, {"title": "Coffee Cup Calorimeter Example .txt", "text": "To find a molecular weight, we simply add up the atomic weight of each atom."}, {"title": "Coffee Cup Calorimeter Example .txt", "text": "So, 23 moles per gram, or grams per mole for sodium, plus 16 grams/mol for oxygen, plus 1 gram/mol for h, and we get 40 grams/mol times the number of moles."}, {"title": "Coffee Cup Calorimeter Example .txt", "text": "Moles cancel, and we get 10 grams of sodium hydroxide mixed into our solution."}, {"title": "Coffee Cup Calorimeter Example .txt", "text": "Our third step is to follow the same exact steps that we just followed just for hydrophoric acid."}, {"title": "Coffee Cup Calorimeter Example .txt", "text": "So find the moles."}, {"title": "Coffee Cup Calorimeter Example .txt", "text": "1 mol per liter times zero point 25 liters gets you zero point 25 moles of hydrofluoric acid."}, {"title": "Coffee Cup Calorimeter Example .txt", "text": "Now, the same step, we have to find a molecular weight of hydrochloric acid."}, {"title": "Coffee Cup Calorimeter Example .txt", "text": "Multiplies that by our moles, and we get grams."}, {"title": "Coffee Cup Calorimeter Example .txt", "text": "So 1 gram/mol for h plus 35.5 grams per mole for chlorine, and we get 36.5\ngrams per mole times zero point 25 moles."}, {"title": "Coffee Cup Calorimeter Example .txt", "text": "Moles cancel, and we get 9.13 grams of hydrochloric acid."}, {"title": "Coffee Cup Calorimeter Example .txt", "text": "Finally, we use our formula to find the energy change, and we get the total mass ten plus 9.13."}, {"title": "Coffee Cup Calorimeter Example .txt", "text": "So 19.13 grams times 4.18\njoules per celsius times gram, which we get from here."}, {"title": "Coffee Cup Calorimeter Example .txt", "text": "And our t final minus t initial so 31 -23 and we get 640 joules."}, {"title": "Coffee Cup Calorimeter Example .txt", "text": "But this corresponds to 00:25 moles of HCL and 00:25 moles of soyu hydroxide."}, {"title": "Coffee Cup Calorimeter Example .txt", "text": "We want to find what corresponds to 1 mol of each."}, {"title": "Coffee Cup Calorimeter Example .txt", "text": "So we basically have to multiply this guy by four, or we could divide this guy by 00:25."}, {"title": "Coffee Cup Calorimeter Example .txt", "text": "We get the same answer."}, {"title": "Coffee Cup Calorimeter Example .txt", "text": "So 640 joules divided by zero point 250 mole gets you 2560 joules per mole."}, {"title": "Coffee Cup Calorimeter Example .txt", "text": "And that's our final answer."}, {"title": "Coffee Cup Calorimeter Example .txt", "text": "So 2560 Joules are released when this guy is mixed."}, {"title": "Coffee Cup Calorimeter Example .txt", "text": "So that's why our water inside is heated to this temperature."}, {"title": "Coffee Cup Calorimeter Example .txt", "text": "Because this amount of energy energy is released into our solution to our water, into the system."}, {"title": "Coffee Cup Calorimeter Example .txt", "text": "And that heats our solution."}, {"title": "Principal Azimuthal Magnetic and Spin Quantum Numbers .txt", "text": "So, just like any given car in any given state has a unique license plate number every electron in any given atom has a unique license plate number."}, {"title": "Principal Azimuthal Magnetic and Spin Quantum Numbers .txt", "text": "Composed of quantum numbers."}, {"title": "Principal Azimuthal Magnetic and Spin Quantum Numbers .txt", "text": "So quantum numbers are simply the identification numbers for electrons in atoms."}, {"title": "Principal Azimuthal Magnetic and Spin Quantum Numbers .txt", "text": "And each unique electron in any given atom has exactly four quantum numbers which make it unique."}, {"title": "Principal Azimuthal Magnetic and Spin Quantum Numbers .txt", "text": "So these four quantum numbers is like the ID badge of that unique electron."}, {"title": "Principal Azimuthal Magnetic and Spin Quantum Numbers .txt", "text": "So let's look at these four quantum numbers."}, {"title": "Principal Azimuthal Magnetic and Spin Quantum Numbers .txt", "text": "The first quantum number is called the principal quantum number, N. So it's represented by the lowercase letter N. And this number begins with one and could be 2345."}, {"title": "Principal Azimuthal Magnetic and Spin Quantum Numbers .txt", "text": "So N has to be a positive whole number."}, {"title": "Principal Azimuthal Magnetic and Spin Quantum Numbers .txt", "text": "Now, this quantum number, the principal quantum number, designates the shell level or the energy level in which the electron is located."}, {"title": "Principal Azimuthal Magnetic and Spin Quantum Numbers .txt", "text": "The Larger the n, the Larger Our size or The Larger The Size Of The Atom and The Greater The energy."}, {"title": "Principal Azimuthal Magnetic and Spin Quantum Numbers .txt", "text": "In other words, an electron found in n equals one is lower in energy than if an electron is found in N equals two."}, {"title": "Principal Azimuthal Magnetic and Spin Quantum Numbers .txt", "text": "So the higher the n, the greater the size of the atom and the greater the energy level in which our electron is in."}, {"title": "Principal Azimuthal Magnetic and Spin Quantum Numbers .txt", "text": "The second quantum number is known as the osmic quantum number and is represented by the lowercase cursive l.\nNow, this quantum number designates the subshell in which our electron is in."}, {"title": "Principal Azimuthal Magnetic and Spin Quantum Numbers .txt", "text": "And the number of subshells."}, {"title": "Principal Azimuthal Magnetic and Spin Quantum Numbers .txt", "text": "This letter N depends on the principal quantum number, and it's given by the following equation l equals n equals one."}, {"title": "Principal Azimuthal Magnetic and Spin Quantum Numbers .txt", "text": "In other words, if we know that our principal quantum number in which our electron is located is n equals four, then our subshell is n minus one So four minus one L equals three."}, {"title": "Principal Azimuthal Magnetic and Spin Quantum Numbers .txt", "text": "And so let's look at some examples of our subshells."}, {"title": "Principal Azimuthal Magnetic and Spin Quantum Numbers .txt", "text": "S is a subshell, P is a subshell, D is a subshell, s is a subshell, and so on."}, {"title": "Principal Azimuthal Magnetic and Spin Quantum Numbers .txt", "text": "Now, these S and P and D are the most familiar ones."}, {"title": "Principal Azimuthal Magnetic and Spin Quantum Numbers .txt", "text": "These guys, you should definitely know."}, {"title": "Principal Azimuthal Magnetic and Spin Quantum Numbers .txt", "text": "Now, for example, s corresponds to l equals zero."}, {"title": "Principal Azimuthal Magnetic and Spin Quantum Numbers .txt", "text": "When our quantum number is N equals one, we get one minus 10."}, {"title": "Principal Azimuthal Magnetic and Spin Quantum Numbers .txt", "text": "So if our electron is found with a principal quantum number of one, that means it must be in subsshell l equals zero, because l equals one minus one gives you zero."}, {"title": "Principal Azimuthal Magnetic and Spin Quantum Numbers .txt", "text": "Likewise, p represents a subshell of l equals 1d represents a subsshell of l equals two, f represents a subshell of l equals three, and so on."}, {"title": "Principal Azimuthal Magnetic and Spin Quantum Numbers .txt", "text": "Now, every subshell has a certain shape."}, {"title": "Principal Azimuthal Magnetic and Spin Quantum Numbers .txt", "text": "In other words, every subshell has an orbital that has a certain shape."}, {"title": "Principal Azimuthal Magnetic and Spin Quantum Numbers .txt", "text": "And the shape of the orbitals in any subshell represents the most probable location of our electrons."}, {"title": "Principal Azimuthal Magnetic and Spin Quantum Numbers .txt", "text": "So shapes are based on mathematical probabilities where our electrons are located."}, {"title": "Principal Azimuthal Magnetic and Spin Quantum Numbers .txt", "text": "So let's look at the shape of our S. S has a spherical shape."}, {"title": "Principal Azimuthal Magnetic and Spin Quantum Numbers .txt", "text": "And what that basically means what this shape means is that there's a 90% chance that our electron will be found within this sphere."}, {"title": "Principal Azimuthal Magnetic and Spin Quantum Numbers .txt", "text": "In other words, if we know that our N is equal to zero, or actually M equals one, m can't be zero."}, {"title": "Principal Azimuthal Magnetic and Spin Quantum Numbers .txt", "text": "If M equals one, that means our L equals zero."}, {"title": "Principal Azimuthal Magnetic and Spin Quantum Numbers .txt", "text": "So that means our subshale must be S. And that means that if this was our proton, there is a 90% chance, 90% probability that our electron is found within this skier."}, {"title": "Principal Azimuthal Magnetic and Spin Quantum Numbers .txt", "text": "Likewise, let's look at the P orbital."}, {"title": "Principal Azimuthal Magnetic and Spin Quantum Numbers .txt", "text": "The P orbital has the following shape."}, {"title": "Principal Azimuthal Magnetic and Spin Quantum Numbers .txt", "text": "And what this P orbital states is there's a 90% probability that our electron is found within this weird shape."}, {"title": "Principal Azimuthal Magnetic and Spin Quantum Numbers .txt", "text": "Now, for this guy, N must be equal to two."}, {"title": "Principal Azimuthal Magnetic and Spin Quantum Numbers .txt", "text": "Because if M equals to two, our L will be one."}, {"title": "Principal Azimuthal Magnetic and Spin Quantum Numbers .txt", "text": "And we see that P has a subshell of one."}, {"title": "Principal Azimuthal Magnetic and Spin Quantum Numbers .txt", "text": "So this guy corresponds to M equals one, and actually M equals two, and L equals one."}, {"title": "Principal Azimuthal Magnetic and Spin Quantum Numbers .txt", "text": "Now let's look at the third quantum number."}, {"title": "Principal Azimuthal Magnetic and Spin Quantum Numbers .txt", "text": "The third quantum number is called the magnetic quantum number."}, {"title": "Principal Azimuthal Magnetic and Spin Quantum Numbers .txt", "text": "And this guy is designated by a lowercase M with a subscript L.\nSo ML for magnetic quantum number."}, {"title": "Principal Azimuthal Magnetic and Spin Quantum Numbers .txt", "text": "The Magnetic Quantum Number designates the exact orbital in which our electron is in."}, {"title": "Principal Azimuthal Magnetic and Spin Quantum Numbers .txt", "text": "Now recall that every subshell L has a certain amount of orbitals, right?"}, {"title": "Principal Azimuthal Magnetic and Spin Quantum Numbers .txt", "text": "When our M equals one, they were talking about the S orbital or L equals zero subshell."}, {"title": "Principal Azimuthal Magnetic and Spin Quantum Numbers .txt", "text": "And this guy has only one orbital, namely the S orbital."}, {"title": "Principal Azimuthal Magnetic and Spin Quantum Numbers .txt", "text": "If our principal quantum number, N is two, that means two minus one."}, {"title": "Principal Azimuthal Magnetic and Spin Quantum Numbers .txt", "text": "Our L, our second quantum number, is one."}, {"title": "Principal Azimuthal Magnetic and Spin Quantum Numbers .txt", "text": "And that means there are three orbitals."}, {"title": "Principal Azimuthal Magnetic and Spin Quantum Numbers .txt", "text": "Now, these guys are the p orbitals."}, {"title": "Principal Azimuthal Magnetic and Spin Quantum Numbers .txt", "text": "Remember, there are three P orbitals."}, {"title": "Principal Azimuthal Magnetic and Spin Quantum Numbers .txt", "text": "There's one in the X direction."}, {"title": "Principal Azimuthal Magnetic and Spin Quantum Numbers .txt", "text": "So if we draw our XYZ axis, our three dimensional axis, that means our P orbital is in the X direction, our PY orbital is in the Y direction, and our PD orbital is in the Z direction."}, {"title": "Principal Azimuthal Magnetic and Spin Quantum Numbers .txt", "text": "In other words, if we put all these guys together, we get three orbitals."}, {"title": "Principal Azimuthal Magnetic and Spin Quantum Numbers .txt", "text": "And these guys are all perpendicular to each other."}, {"title": "Principal Azimuthal Magnetic and Spin Quantum Numbers .txt", "text": "Why?"}, {"title": "Principal Azimuthal Magnetic and Spin Quantum Numbers .txt", "text": "Well, because these lines, the Z and the X axis, the X and the Y axis, and the Z and the Y axis are all perpendicular to each other."}, {"title": "Principal Azimuthal Magnetic and Spin Quantum Numbers .txt", "text": "So all these three guys PX, PY, and PZ must be perpendicular."}, {"title": "Principal Azimuthal Magnetic and Spin Quantum Numbers .txt", "text": "Now, our range for our Magnetic quantum numbers can be derived using our L. Our range begins at minus L and goes to plus L. So our PX begins at negative L.\nAnd since this guy represents L equals one, that means our PX must be L minus one or minus one."}, {"title": "Principal Azimuthal Magnetic and Spin Quantum Numbers .txt", "text": "So our ML is minus one."}, {"title": "Principal Azimuthal Magnetic and Spin Quantum Numbers .txt", "text": "Now, the next number after minus one is zero."}, {"title": "Principal Azimuthal Magnetic and Spin Quantum Numbers .txt", "text": "Right?"}, {"title": "Principal Azimuthal Magnetic and Spin Quantum Numbers .txt", "text": "We're adding increments of one."}, {"title": "Principal Azimuthal Magnetic and Spin Quantum Numbers .txt", "text": "And that means our PY must have an ML of equals zero."}, {"title": "Principal Azimuthal Magnetic and Spin Quantum Numbers .txt", "text": "And our final number is plus L, so plus one."}, {"title": "Principal Azimuthal Magnetic and Spin Quantum Numbers .txt", "text": "So our ML for PD, the final orbital is plus one."}, {"title": "Principal Azimuthal Magnetic and Spin Quantum Numbers .txt", "text": "Now let's look at the final quantum number."}, {"title": "Principal Azimuthal Magnetic and Spin Quantum Numbers .txt", "text": "The final quantum number is known as the electron spin quantum number."}, {"title": "Principal Azimuthal Magnetic and Spin Quantum Numbers .txt", "text": "And this guy is represented by also a lowercase M but with a subscript S S for spin."}, {"title": "Principal Azimuthal Magnetic and Spin Quantum Numbers .txt", "text": "Now, every orbital can have a maximum of two electrons."}, {"title": "Principal Azimuthal Magnetic and Spin Quantum Numbers .txt", "text": "And what the Pole Exclusion Principle tells us is it states that any two electrons in any given atom can never have the same four quantum numbers."}, {"title": "Principal Azimuthal Magnetic and Spin Quantum Numbers .txt", "text": "Remember, just like any car in any given state can only have one license plate one unique license plate any unique electron in any given atom will only have four quantum numbers unique to that electron."}, {"title": "Principal Azimuthal Magnetic and Spin Quantum Numbers .txt", "text": "So that's what the poly exclusion principle tells us."}, {"title": "Principal Azimuthal Magnetic and Spin Quantum Numbers .txt", "text": "And that means since any given orbital can have a maximum of two electrons there are two possible spin numbers or quantum spin numbers plus one two and minus one two."}, {"title": "Principal Azimuthal Magnetic and Spin Quantum Numbers .txt", "text": "So I want to mention briefly two more important notes about quantum numbers."}, {"title": "Principal Azimuthal Magnetic and Spin Quantum Numbers .txt", "text": "Now, to find a total number of orbitals in any given shell level with any given principal quantum number we simply take that principal quantum number and square it."}, {"title": "Principal Azimuthal Magnetic and Spin Quantum Numbers .txt", "text": "So for N equals one there are one squared to one orbital."}, {"title": "Principal Azimuthal Magnetic and Spin Quantum Numbers .txt", "text": "And that makes sense because when N equals one L equals zero and we have only the S orbital."}, {"title": "Principal Azimuthal Magnetic and Spin Quantum Numbers .txt", "text": "For M equals two there are two squared to four total orbitals."}, {"title": "Principal Azimuthal Magnetic and Spin Quantum Numbers .txt", "text": "And that also makes sense that we have the SPSP one and PZ a total of four orbitals."}, {"title": "Principal Azimuthal Magnetic and Spin Quantum Numbers .txt", "text": "For M equals three, there are nine orbitals."}, {"title": "Principal Azimuthal Magnetic and Spin Quantum Numbers .txt", "text": "For M equals four, there are 16 orbitals and so on."}, {"title": "Principal Azimuthal Magnetic and Spin Quantum Numbers .txt", "text": "Now, one last thing I want to mention is if we look at our periodic table what each period represents is a new energy level, a new shell level."}, {"title": "Principal Azimuthal Magnetic and Spin Quantum Numbers .txt", "text": "So period number one, all the elements have a shell level of one."}, {"title": "Principal Azimuthal Magnetic and Spin Quantum Numbers .txt", "text": "In period two, all the elements have a shell level of two."}, {"title": "Principal Azimuthal Magnetic and Spin Quantum Numbers .txt", "text": "In period three, all the elements have a shell level of four and so on."}, {"title": "Principal Azimuthal Magnetic and Spin Quantum Numbers .txt", "text": "So each guide, each row, each period represents a new energy level."}, {"title": "Cis-Trans and Z-E Isomerism .txt", "text": "So let's recall what anisomer is."}, {"title": "Cis-Trans and Z-E Isomerism .txt", "text": "So two compounds are said to be isomers, where they have the same exact molecular formula but different structures."}, {"title": "Cis-Trans and Z-E Isomerism .txt", "text": "So in this lecture, we're going to focus on cystrend ze isomers."}, {"title": "Cis-Trans and Z-E Isomerism .txt", "text": "So let's begin by looking at the following alkane that has the following molecular formula c two, H two to XY, where XY are simply two different compounds, molecules or atoms that are not H atoms."}, {"title": "Cis-Trans and Z-E Isomerism .txt", "text": "And let's begin by trying to figure out the three dimensional structure of this alkene."}, {"title": "Cis-Trans and Z-E Isomerism .txt", "text": "So, alkines have the following structure."}, {"title": "Cis-Trans and Z-E Isomerism .txt", "text": "So we have a double bond."}, {"title": "Cis-Trans and Z-E Isomerism .txt", "text": "The lower bond is a sigma bond."}, {"title": "Cis-Trans and Z-E Isomerism .txt", "text": "The upper bond is our Pi bond."}, {"title": "Cis-Trans and Z-E Isomerism .txt", "text": "So lower bond, sigma, upper pi bond."}, {"title": "Cis-Trans and Z-E Isomerism .txt", "text": "We have the two intersections."}, {"title": "Cis-Trans and Z-E Isomerism .txt", "text": "So these are the carbon atoms shown here."}, {"title": "Cis-Trans and Z-E Isomerism .txt", "text": "And here we have the two H atoms given the red and the x atom, the green atom and the Y atom, the blue atom."}, {"title": "Cis-Trans and Z-E Isomerism .txt", "text": "Now, one important detail about the structure of alkanes is that they have planar symmetry."}, {"title": "Cis-Trans and Z-E Isomerism .txt", "text": "In other words, all these four atoms are found on the same exact plane."}, {"title": "Cis-Trans and Z-E Isomerism .txt", "text": "So this was the XY plane."}, {"title": "Cis-Trans and Z-E Isomerism .txt", "text": "All these four atoms would be on the same plane."}, {"title": "Cis-Trans and Z-E Isomerism .txt", "text": "And these four bonds are also on the same plane."}, {"title": "Cis-Trans and Z-E Isomerism .txt", "text": "Now, whenever we have the two HS on the same side of the plane, or the x and Y, the heavier atoms on the same side of the plane, we have CITs or Z compounds or molecules."}, {"title": "Cis-Trans and Z-E Isomerism .txt", "text": "In other words, we define C compounds as hydrogens being on the same side."}, {"title": "Cis-Trans and Z-E Isomerism .txt", "text": "And we define Z compounds as having the heavier groups on the same side."}, {"title": "Cis-Trans and Z-E Isomerism .txt", "text": "Remember, we define x and Y to be any compound, molecule or atom that is different than H. And that means our x and Y are both heavier than H's."}, {"title": "Cis-Trans and Z-E Isomerism .txt", "text": "So this compound is one isomer of this molecular formula and it's the sys or Z isomer."}, {"title": "Cis-Trans and Z-E Isomerism .txt", "text": "What about trans or e?"}, {"title": "Cis-Trans and Z-E Isomerism .txt", "text": "Well, let's recall another important detail about alkenes."}, {"title": "Cis-Trans and Z-E Isomerism .txt", "text": "Alkines have double bonds, and that means we can't rotate this molecule."}, {"title": "Cis-Trans and Z-E Isomerism .txt", "text": "The only way we rotate this lower bond is if we break the Pi bond."}, {"title": "Cis-Trans and Z-E Isomerism .txt", "text": "The only way we break the Pi bond is if we input energy."}, {"title": "Cis-Trans and Z-E Isomerism .txt", "text": "So let's say we input energy, exactly 66 energy."}, {"title": "Cis-Trans and Z-E Isomerism .txt", "text": "Then we'll break the Pi bond and our bond, our CC bond, the lower CC bond will rotate."}, {"title": "Cis-Trans and Z-E Isomerism .txt", "text": "And then let's suppose it rotates."}, {"title": "Cis-Trans and Z-E Isomerism .txt", "text": "We take away the energy and our Pi bond reforms."}, {"title": "Cis-Trans and Z-E Isomerism .txt", "text": "We will get the following molecule."}, {"title": "Cis-Trans and Z-E Isomerism .txt", "text": "So, in this molecule, we have the HS are on the opposite sides, and the x and Y are also on the opposite sides."}, {"title": "Cis-Trans and Z-E Isomerism .txt", "text": "So we have the following picture."}, {"title": "Cis-Trans and Z-E Isomerism .txt", "text": "So we have the two HS being on different sides, and we have the Y and the X also being on different sides."}, {"title": "Cis-Trans and Z-E Isomerism .txt", "text": "So trans is defined the following way."}, {"title": "Cis-Trans and Z-E Isomerism .txt", "text": "Hydrogens are on different sides of the plane, x and x, I mean H and H different sides."}, {"title": "Cis-Trans and Z-E Isomerism .txt", "text": "And E is defined as the heavier groups are in different sides."}, {"title": "Cis-Trans and Z-E Isomerism .txt", "text": "So, once again, our X and Y are in different signs."}, {"title": "Cis-Trans and Z-E Isomerism .txt", "text": "Now, these two guides are isomers to one another, and they're separated by 66 kilotons of mole."}, {"title": "Cis-Trans and Z-E Isomerism .txt", "text": "So let's look at the following few examples, and let's try to figure out which ones are E and which ones are Z."}, {"title": "Cis-Trans and Z-E Isomerism .txt", "text": "So we're looking for the heavier groups and the lighter groups."}, {"title": "Cis-Trans and Z-E Isomerism .txt", "text": "So we have two methyl groups and two Ethyl groups."}, {"title": "Cis-Trans and Z-E Isomerism .txt", "text": "Ethyl is heavier."}, {"title": "Cis-Trans and Z-E Isomerism .txt", "text": "That means these guys found on the same side are the heavier groups."}, {"title": "Cis-Trans and Z-E Isomerism .txt", "text": "And so we have the heavier groups on the same side."}, {"title": "Cis-Trans and Z-E Isomerism .txt", "text": "So that means we have our Z."}, {"title": "Cis-Trans and Z-E Isomerism .txt", "text": "So this must be Z."}, {"title": "Cis-Trans and Z-E Isomerism .txt", "text": "So what about this guy here?"}, {"title": "Cis-Trans and Z-E Isomerism .txt", "text": "We also have methyl and Ethyl."}, {"title": "Cis-Trans and Z-E Isomerism .txt", "text": "But the Ethyl groups are different size, and the methyl groups are the same size."}, {"title": "Cis-Trans and Z-E Isomerism .txt", "text": "So that means the lighter are on the same sides."}, {"title": "Cis-Trans and Z-E Isomerism .txt", "text": "On different sides, the heavier are a different size."}, {"title": "Cis-Trans and Z-E Isomerism .txt", "text": "So that means we must have our E.\nSo this is E. What about this guy?"}, {"title": "Cis-Trans and Z-E Isomerism .txt", "text": "Well, now we have a methyl."}, {"title": "Cis-Trans and Z-E Isomerism .txt", "text": "We have an h group."}, {"title": "Cis-Trans and Z-E Isomerism .txt", "text": "We have a methyl and an Ethyl."}, {"title": "Cis-Trans and Z-E Isomerism .txt", "text": "So once again, we have the two ethyls on different sides, the two heavier groups."}, {"title": "Cis-Trans and Z-E Isomerism .txt", "text": "And that means we must have our E.\nWell, what about this last one?"}, {"title": "Cis-Trans and Z-E Isomerism .txt", "text": "Here we have two methyl groups attached to the same carbon."}, {"title": "Cis-Trans and Z-E Isomerism .txt", "text": "So these two groups are identical."}, {"title": "Cis-Trans and Z-E Isomerism .txt", "text": "And that means there's no way to distinguish between these two guys because they have the same exact weight."}, {"title": "Cis-Trans and Z-E Isomerism .txt", "text": "And that means there are no isomers of this compound."}, {"title": "Cis-Trans and Z-E Isomerism .txt", "text": "E or or fists or trans do not exist for this guy."}, {"title": "Phase Change .txt", "text": "A phase."}, {"title": "Phase Change .txt", "text": "Change is a physical process by which a substance goes from one phase to another phase."}, {"title": "Phase Change .txt", "text": "Now let's look at melting, freezing, vaporization and condensation."}, {"title": "Phase Change .txt", "text": "Melting is the process by which a solid becomes a liquid."}, {"title": "Phase Change .txt", "text": "And in this process, energy input is required."}, {"title": "Phase Change .txt", "text": "So the process is endothelial."}, {"title": "Phase Change .txt", "text": "Thermic melting is endothermic."}, {"title": "Phase Change .txt", "text": "The enthalpy of fusion is simply the energy input required to melt something."}, {"title": "Phase Change .txt", "text": "And this guy is the same as this guy, so it's also positive."}, {"title": "Phase Change .txt", "text": "So in melting, the potential energy of our substance, of our solid, is increased."}, {"title": "Phase Change .txt", "text": "And the atrium molecular bonds connecting the solid are broken so that eventually they can become liquid molecules."}, {"title": "Phase Change .txt", "text": "So freezing is the opposite of melting."}, {"title": "Phase Change .txt", "text": "Freezing is the process by which a liquid becomes a solid."}, {"title": "Phase Change .txt", "text": "In this process, internal energy of our system, of our liquid, decreases until eventually it becomes a solid."}, {"title": "Phase Change .txt", "text": "That means energy is released the environment."}, {"title": "Phase Change .txt", "text": "Okay, so it's exothermic."}, {"title": "Phase Change .txt", "text": "So the entropy of freezing is negative."}, {"title": "Phase Change .txt", "text": "It's the same magnitude as the enthalpy of fusion, but it's negative."}, {"title": "Phase Change .txt", "text": "So now let's look at vaporization."}, {"title": "Phase Change .txt", "text": "Vaporization is a process by which a liquid becomes a gas."}, {"title": "Phase Change .txt", "text": "And in this situation, energy input is also required, just like in melting."}, {"title": "Phase Change .txt", "text": "And that's because the potential edge of the bonds is required to increase."}, {"title": "Phase Change .txt", "text": "So energy input into our system from the environment is required."}, {"title": "Phase Change .txt", "text": "So the enthalpy of vaporization is positive."}, {"title": "Phase Change .txt", "text": "Now let's look at condensation."}, {"title": "Phase Change .txt", "text": "Condensation is the opposite of vaporization."}, {"title": "Phase Change .txt", "text": "It's the process by which a gas molecule goes back into the liquid state and condensation, just like freezing, is exothermic."}, {"title": "Phase Change .txt", "text": "When a gas becomes a liquid, energy is released of the environment because the internal energy of our system decreases."}, {"title": "Phase Change .txt", "text": "So energy is released and the change in enthalpy of condensation is negative."}, {"title": "Le Chatelier\u2019s Principle .txt", "text": "Now, suppose we have a chemical reaction that has achieved equilibrium."}, {"title": "Le Chatelier\u2019s Principle .txt", "text": "And I want to ask the question how does our chemical equilibrium change when we change the following things when we increase or decrease temperature, when we increase or decrease pressure or when we change the concentrations of reactions or products."}, {"title": "Le Chatelier\u2019s Principle .txt", "text": "Now, these questions and many others can be answered using a principle known as Lusciously as principle."}, {"title": "Le Chatelier\u2019s Principle .txt", "text": "And what this principle states is that whenever a system at equilibrium is stressed it will respond by shifting equilibrium in the direction that tends to decrease that stress."}, {"title": "Le Chatelier\u2019s Principle .txt", "text": "Now, let's look at three stresses temperature, pressure and concentrations."}, {"title": "Le Chatelier\u2019s Principle .txt", "text": "So let's begin with temperature."}, {"title": "Le Chatelier\u2019s Principle .txt", "text": "Suppose we have the following reaction in which 1 mol of among the gas state reacts with three moles of diatomic H two plus the gas state to produce two moles of ammonia alter the gas state and heat."}, {"title": "Le Chatelier\u2019s Principle .txt", "text": "So this is an exothermic reaction."}, {"title": "Le Chatelier\u2019s Principle .txt", "text": "Now, whenever we're talking about lushly as principle and we see that we have heat produced or heat in the beginning, that means we can treat this heat sky as a product."}, {"title": "Le Chatelier\u2019s Principle .txt", "text": "So our heat is tangible, okay?"}, {"title": "Le Chatelier\u2019s Principle .txt", "text": "So now let's increase the temperature of our system of our reaction."}, {"title": "Le Chatelier\u2019s Principle .txt", "text": "Now, we increase temperature by adding energy and that means we're adding heat."}, {"title": "Le Chatelier\u2019s Principle .txt", "text": "Now, if we're adding heat, that means one of our products, namely the heat guide is increased."}, {"title": "Le Chatelier\u2019s Principle .txt", "text": "So the concentration is not really concentration but you could think of energy concentration of our heat increases."}, {"title": "Le Chatelier\u2019s Principle .txt", "text": "Now, if you think of this as the reaction quotient, that means our ratio will increase."}, {"title": "Le Chatelier\u2019s Principle .txt", "text": "So our Q will become greater than our K.\nAnd that means as K is bigger than Q, there will be a leftward shift of equilibrium."}, {"title": "Le Chatelier\u2019s Principle .txt", "text": "In other words, these guys will tend to react to convert back to our reactants, namely these two guys."}, {"title": "Le Chatelier\u2019s Principle .txt", "text": "So we see that whenever we're talking about an exothermic reaction in which he's produced increasing temperature of our system will shift equilibrium to the left this way."}, {"title": "Le Chatelier\u2019s Principle .txt", "text": "So in this case, the reverse reaction is more favored than a four reaction."}, {"title": "Le Chatelier\u2019s Principle .txt", "text": "So let's reverse the case."}, {"title": "Le Chatelier\u2019s Principle .txt", "text": "Let's say we're dealing with an endothermic reaction in which heat is added to our ammonia molecules to create our products."}, {"title": "Le Chatelier\u2019s Principle .txt", "text": "So now these guys are products and these guys are reactants."}, {"title": "Le Chatelier\u2019s Principle .txt", "text": "Now, what happens if we increase temperature?"}, {"title": "Le Chatelier\u2019s Principle .txt", "text": "Well, now we have the reverse case."}, {"title": "Le Chatelier\u2019s Principle .txt", "text": "Now, one of our reactants, its concentration increases."}, {"title": "Le Chatelier\u2019s Principle .txt", "text": "And that means our Q, our quotient reaction quotient decreases, becomes smaller than K. And that means increasing temperature of an endothermic reaction will shift it to the right."}, {"title": "Le Chatelier\u2019s Principle .txt", "text": "We're going to see a leftward shift in equilibrium."}, {"title": "Le Chatelier\u2019s Principle .txt", "text": "So the reactants will tend to react to produce our products, our end in the gas state and three moles of H two in the gas state."}, {"title": "Le Chatelier\u2019s Principle .txt", "text": "Now, some exceptions to Lusciously as principle exists."}, {"title": "Le Chatelier\u2019s Principle .txt", "text": "Now, at very high temperatures, entropy takes over."}, {"title": "Le Chatelier\u2019s Principle .txt", "text": "And that's because entropy is dictated by the following reaction in which change in gigs, free energy is equal to change in entropy minus temperature times change in entropy."}, {"title": "Le Chatelier\u2019s Principle .txt", "text": "So, if temperature is high enough and we have a positive change in entropy, even if we have an endothermic or an exothermic reaction, it doesn't matter what reaction we have."}, {"title": "Le Chatelier\u2019s Principle .txt", "text": "At a very high temperature with very positive entropy, we're always going to get a negative gives free energy."}, {"title": "Le Chatelier\u2019s Principle .txt", "text": "And so, our reaction will always tend to be this way in a rightward direction."}, {"title": "Le Chatelier\u2019s Principle .txt", "text": "Now, let's talk about pressure."}, {"title": "Le Chatelier\u2019s Principle .txt", "text": "Suppose once again we have the following exostobic reaction."}, {"title": "Le Chatelier\u2019s Principle .txt", "text": "And now, suppose we try to increase our pressure at constant temperature, so we decrease our volume."}, {"title": "Le Chatelier\u2019s Principle .txt", "text": "And so, the pressure of our system, the pressure of the molecules exert on the wall of the container increases."}, {"title": "Le Chatelier\u2019s Principle .txt", "text": "So what will happen?"}, {"title": "Le Chatelier\u2019s Principle .txt", "text": "Well, increasing, or according to Lush of Global principle, increasing pressure by decreasing volume at constant temperature, by making our system smaller, by shrinking, it will shift the equilibrium in a direction where there are less molecules present."}, {"title": "Le Chatelier\u2019s Principle .txt", "text": "In other words, let's see how many molecules we have on the reactant side and how many molecules we have on the product side."}, {"title": "Le Chatelier\u2019s Principle .txt", "text": "Well, according to this formula, we have one and three."}, {"title": "Le Chatelier\u2019s Principle .txt", "text": "So, four molecules, four moles of molecules on our reactive side, and only two moles of molecules on our product side."}, {"title": "Le Chatelier\u2019s Principle .txt", "text": "So that means, by decreasing volume, thereby increasing pressure, our system will shift this way, rightward?"}, {"title": "Le Chatelier\u2019s Principle .txt", "text": "Because if our system goes this way, it's going to produce on average, less moles of molecules than on this side."}, {"title": "Le Chatelier\u2019s Principle .txt", "text": "So, our system will try to counter the increase in pressure by decreasing the pressure by going this way to decrease the number of total molecules found in our system."}, {"title": "Le Chatelier\u2019s Principle .txt", "text": "If we have less molecules in our system, that means less molecules are colliding with the walls of our container."}, {"title": "Le Chatelier\u2019s Principle .txt", "text": "And so, our overall total pressure is less."}, {"title": "Le Chatelier\u2019s Principle .txt", "text": "And finally, let's look at how concentration affects our equilibrium of our reaction according to Leslie Lee's principle."}, {"title": "Le Chatelier\u2019s Principle .txt", "text": "Now, let's look at the same reaction."}, {"title": "Le Chatelier\u2019s Principle .txt", "text": "1 mol of them react to three moles of H two and gas state to produce two moles of ammonia and heat an exothermic reaction."}, {"title": "Le Chatelier\u2019s Principle .txt", "text": "So, how will increasing reactants change our equilibrium?"}, {"title": "Le Chatelier\u2019s Principle .txt", "text": "Well, increasing the concentration of either or both the reactants shifts equilibrium to the right."}, {"title": "Le Chatelier\u2019s Principle .txt", "text": "So, a right workshift in equilibrium, while increasing concentration of our products, any of the products of both the products shifts our equilibrium to the left."}, {"title": "Le Chatelier\u2019s Principle .txt", "text": "So, increasing this guy will shift our equilibrium to the left, producing more of our reactants."}, {"title": "Le Chatelier\u2019s Principle .txt", "text": "So, why is that?"}, {"title": "Le Chatelier\u2019s Principle .txt", "text": "Well, let's see once again, what happens when we increase the concentrations of this guy and this guy."}, {"title": "Le Chatelier\u2019s Principle .txt", "text": "Well, recall what the reaction quotient states."}, {"title": "Le Chatelier\u2019s Principle .txt", "text": "If you increase the concentration of our reactants, then our reaction quotient will become larger than our equilibrium constant K. And if Q is larger than K, that means we're going to observe a rightward shift in equilibrium in other words, the forward reaction will proceed this way at a higher rate than the reverse reaction."}, {"title": "Le Chatelier\u2019s Principle .txt", "text": "So these guys will want to convert to decrease the overall concentration of our reactants so that our Q can become our K again."}, {"title": "Le Chatelier\u2019s Principle .txt", "text": "In other words, Q will tend to move towards K. Likewise, if we increase the concentration of products."}, {"title": "Le Chatelier\u2019s Principle .txt", "text": "That means our q will become a less than K.\nAnd since q will want to move towards K, this concentration will tend to decreasing therefore providing a leftward shift in equilibrium."}, {"title": "Le Chatelier\u2019s Principle .txt", "text": "I want to mention one last important note what will happen if we add some other arbitrary molecule that is not present in our reaction?"}, {"title": "Le Chatelier\u2019s Principle .txt", "text": "Such as for example, diatomic CO2 in our gas state?"}, {"title": "Le Chatelier\u2019s Principle .txt", "text": "Well, to answer this question, let's look at our partial pressure equilibrium constant."}, {"title": "Le Chatelier\u2019s Principle .txt", "text": "And the reason we're using partial pressures is because every single reactant is in the gas state."}, {"title": "Le Chatelier\u2019s Principle .txt", "text": "Let me just add the G and G for gas."}, {"title": "Le Chatelier\u2019s Principle .txt", "text": "So our equilibrium or partial pressure equilibrium constant given by KP equals the partial pressure of our product to the second power because we have a two coefficient divided by the partial pressure due to this gas molecule times the partial pressure due to this gas molecule to the third power."}, {"title": "Le Chatelier\u2019s Principle .txt", "text": "The third comes from the coefficient and the one here comes from the one coefficient."}, {"title": "Le Chatelier\u2019s Principle .txt", "text": "Notice that our gas molecule, this one does not appear in our equilibrium expression and that means adding this guide will have no effect on our chemical equilibrium and in fact, adding any other molecule, for example helium to our mixture will not do anything to our chemical equilibrium."}, {"title": "Le Chatelier\u2019s Principle .txt", "text": "And that's an important point to understand only increasing the concentrations of molecules that are actually present in our reaction in our equilibrium expression will affect our chemical equilibrium."}, {"title": "Le Chatelier\u2019s Principle .txt", "text": "And because this molecule molecule is imprisoned, it will have no effect on our chemical equilibrium."}, {"title": "pH example #1.txt", "text": "In this example, we begin with 300 MLS of water and zero point 46 grams of nitric acid."}, {"title": "pH example #1.txt", "text": "We want to find our PH of our solution."}, {"title": "pH example #1.txt", "text": "So we basically begin with pure water, which has a PH of seven."}, {"title": "pH example #1.txt", "text": "And we added acid, a Bronxed Lyric acid, which will basically dissociate into H plus and the base."}, {"title": "pH example #1.txt", "text": "That means that concentration of our H ions within our solution will increase."}, {"title": "pH example #1.txt", "text": "So our PH should decrease."}, {"title": "pH example #1.txt", "text": "Let's see what we get."}, {"title": "pH example #1.txt", "text": "Exactly."}, {"title": "pH example #1.txt", "text": "So we want to use the formula for a PH."}, {"title": "pH example #1.txt", "text": "But before we use that formula, we have to find the molarity of our solution."}, {"title": "pH example #1.txt", "text": "And the way we find molarity is first we want to find the molecular weight of our solid, but then we want to find the moles of our solid."}, {"title": "pH example #1.txt", "text": "And finally we find the kilograms of solvent."}, {"title": "pH example #1.txt", "text": "We divide moles of solid by kilograms of solvent."}, {"title": "pH example #1.txt", "text": "We get molarity, plug that into our PH formula, and we find our result."}, {"title": "pH example #1.txt", "text": "So let's begin."}, {"title": "pH example #1.txt", "text": "Molecular weight of our nitric acid is simply calculated by adding up the atomic weights of each respective atom."}, {"title": "pH example #1.txt", "text": "So 1 gram/mol for H plus 14 grams/mol for N plus three times."}, {"title": "pH example #1.txt", "text": "Because we have a subscription of 316 grams per mole for O, gives you a molecular weight of 63 grams/mol for nitric acid."}, {"title": "pH example #1.txt", "text": "Now, to find the moles of nitric acid, we take our grams of nitric acid, divide that by our molecular weight grams cancel, moles goes on top, and we get zero point 73 moles of nitric acid."}, {"title": "pH example #1.txt", "text": "So finally, we have to find the kilograms of solvent."}, {"title": "pH example #1.txt", "text": "To find the kilograms of solvent, we take our density of water and multiply it by the volume of water."}, {"title": "pH example #1.txt", "text": "So our density of water, we can look that up, and that's 1 gram per ML times the amount in volume of water."}, {"title": "pH example #1.txt", "text": "300 MLS MLS cancel."}, {"title": "pH example #1.txt", "text": "We get 300 grams of water."}, {"title": "pH example #1.txt", "text": "Now we need kilograms."}, {"title": "pH example #1.txt", "text": "To find kilograms, we simply take this, divide it by 1000, we get 0.3 kg."}, {"title": "pH example #1.txt", "text": "Now, to find Molarity, we simply take our moles of solute, divide that by kilograms of solvent, and we get zero point 24 three molar."}, {"title": "pH example #1.txt", "text": "So that's our Molarity."}, {"title": "pH example #1.txt", "text": "And finally we use our PH formula which basically states PH equals negative log ten of 0.243."}, {"title": "pH example #1.txt", "text": "Our Molarity, plug that into our calculator and we get 1.61."}, {"title": "pH example #1.txt", "text": "So clearly it went from a PH of seven, a neutral, so a very low PH 1.61."}, {"title": "pH example #1.txt", "text": "And this means it's a very acidic solution."}, {"title": "pH example #1.txt", "text": "And that's because this is a very strong Bronzed and Lowry acid."}, {"title": "Autoionization of Water .txt", "text": "In this lecture, we're going to look at the autoimonization of water."}, {"title": "Autoionization of Water .txt", "text": "Now, even the most purified form of water conducts some electricity, and that indicates the presence of ions found within our mixture."}, {"title": "Autoionization of Water .txt", "text": "And since water is the only molecule present in our mixture, that means water must associate."}, {"title": "Autoionization of Water .txt", "text": "And let's see exactly what happens."}, {"title": "Autoionization of Water .txt", "text": "Remember, water can act as both a base and an acid."}, {"title": "Autoionization of Water .txt", "text": "So what actually happens is two water molecules interact in such a way that one acts as a base and one act as an acid."}, {"title": "Autoionization of Water .txt", "text": "So one donates H, and the other one accepts H, forming a conjugate acid and a conjugate base, namely hydronium and hydroxide."}, {"title": "Autoionization of Water .txt", "text": "And this process of dissociation is called autoionization, where the auto basically means that two water molecules interact."}, {"title": "Autoionization of Water .txt", "text": "And ionization means the dissociation of the two water molecules."}, {"title": "Autoionization of Water .txt", "text": "Now, at equilibrium, reactants are favored."}, {"title": "Autoionization of Water .txt", "text": "And that means equilibrium lies far to the left."}, {"title": "Autoionization of Water .txt", "text": "So that means there will be many more water molecules than ions at any given temperature."}, {"title": "Autoionization of Water .txt", "text": "So, equilibrium construction."}, {"title": "Autoionization of Water .txt", "text": "So let's write the equilibrium construction for our reaction above."}, {"title": "Autoionization of Water .txt", "text": "So remember, liquids are not included."}, {"title": "Autoionization of Water .txt", "text": "Only eighthway solutions are included."}, {"title": "Autoionization of Water .txt", "text": "So our KWR constant is equal to the concentration of hydronium times the concentration of hydroxide."}, {"title": "Autoionization of Water .txt", "text": "So kw in this case, when we talk about autoionization, is called the ionization constant for H 20."}, {"title": "Autoionization of Water .txt", "text": "And this depends on temperature."}, {"title": "Autoionization of Water .txt", "text": "And at 25 degrees Celsius, you should know that kw is 1.0 times ten to negative 14."}, {"title": "Autoionization of Water .txt", "text": "Now, notice that our exponents here are one and one."}, {"title": "Autoionization of Water .txt", "text": "That's because we have 1 mol and 1 mol."}, {"title": "Autoionization of Water .txt", "text": "So, since we know our kw, and from experiments, we know that at a PH of seven, our concentration of hydronium is 1.0\ntimes ten to negative seven."}, {"title": "Autoionization of Water .txt", "text": "That means, since we know this guy and this guy, we can find the concentration of hydroxide."}, {"title": "Autoionization of Water .txt", "text": "And we can do it by simply dividing through by 1.0\ntimes ten negative seven."}, {"title": "Autoionization of Water .txt", "text": "And we get x equals 1.0 times ten to negative seven."}, {"title": "Autoionization of Water .txt", "text": "So at a PH of seven, our concentration of hydronium equals that of hydroxide."}, {"title": "Autoionization of Water .txt", "text": "Now, at any given temperature, the ionization constant will always remain the same."}, {"title": "Autoionization of Water .txt", "text": "So at 25 degrees Celsius, this guy will always be 1.0\ntimes ten to negative 14."}, {"title": "Autoionization of Water .txt", "text": "This will only increase with increase in temperature or decrease with decreasing temperature."}, {"title": "Autoionization of Water .txt", "text": "This does not depend on the concentration of this guy, nor on this guy."}, {"title": "Autoionization of Water .txt", "text": "Now, if our hydronium concentration is greater than 1.0 times ten to negative seven, that means our solution is acidic."}, {"title": "Autoionization of Water .txt", "text": "If it's less than 1.0\ntimes ten to seven, it's basic."}, {"title": "Autoionization of Water .txt", "text": "Likewise, if our hydroxide concentration is less than 1.0 times six, negative seven, it's an acidic solution."}, {"title": "Autoionization of Water .txt", "text": "If it's more than 1.0 times six mega seven, it's a basic solution."}, {"title": "Autoionization of Water .txt", "text": "Now, in this last step, I want to look at the expression for kw again."}, {"title": "Autoionization of Water .txt", "text": "And my goal is to take this expression and convert it to this expression."}, {"title": "Autoionization of Water .txt", "text": "This expression will be convenient when we know the PH and we want to find the poh."}, {"title": "Autoionization of Water .txt", "text": "And when we know that poh and we want to find the PH."}, {"title": "Autoionization of Water .txt", "text": "So to go from this guy to this guy, let's first look at a few things."}, {"title": "Autoionization of Water .txt", "text": "Let's review."}, {"title": "Autoionization of Water .txt", "text": "One of the logs of log states that log of X times Y equals log x plus log y."}, {"title": "Autoionization of Water .txt", "text": "The second part I want to look at is the formulas for PH and poh."}, {"title": "Autoionization of Water .txt", "text": "PH is equal to negative log of the hydronium concentration, and Poh is equal to the negative log of the hydroxide concentration."}, {"title": "Autoionization of Water .txt", "text": "Now, in Part C, remember, at 25 degrees Celsius, our Kw will always be 1.0\ntimes 10th to negative 14."}, {"title": "Autoionization of Water .txt", "text": "Now, if we want to take the PH of kw, which is PKW, we simply write PKW is equal to negative log of one times ten to the negative 14."}, {"title": "Autoionization of Water .txt", "text": "Right?"}, {"title": "Autoionization of Water .txt", "text": "Now, I could either plug this guy into the calculator, or I could solve it in my head."}, {"title": "Autoionization of Water .txt", "text": "Now, since we have a negative here and a negative here, negatives cancel."}, {"title": "Autoionization of Water .txt", "text": "So we simply have one times 10th and negative four."}, {"title": "Autoionization of Water .txt", "text": "It's the 14th."}, {"title": "Autoionization of Water .txt", "text": "So since our base is ten, I'll write a base ten."}, {"title": "Autoionization of Water .txt", "text": "Since our exponent is what we don't know, we leave that blank."}, {"title": "Autoionization of Water .txt", "text": "And since this is our result, we plug this into the result."}, {"title": "Autoionization of Water .txt", "text": "So 10th to what power gives you ten to the 14th?"}, {"title": "Autoionization of Water .txt", "text": "Well, 14."}, {"title": "Autoionization of Water .txt", "text": "So x is 14."}, {"title": "Autoionization of Water .txt", "text": "So PKW is 14."}, {"title": "Autoionization of Water .txt", "text": "So let's go back to here."}, {"title": "Autoionization of Water .txt", "text": "Kw is equal to hydronium times hydroxide log of base ten of Kw is equal to log of base ten of this entire guy."}, {"title": "Autoionization of Water .txt", "text": "Using part A, we simply distribute, and we get log of kw is equal to log of this guy plus log of this guy."}, {"title": "Autoionization of Water .txt", "text": "Now, to use part B, I need to multiply the entire statement by negative one."}, {"title": "Autoionization of Water .txt", "text": "And now I can substitute."}, {"title": "Autoionization of Water .txt", "text": "I bring this guy, the PH, into here, and this guy is simply poach goes here, and this guy is simply PKW."}, {"title": "Autoionization of Water .txt", "text": "And now from Part C, I know that PKW is equal to 14."}, {"title": "Autoionization of Water .txt", "text": "So this guy equal to 14."}, {"title": "Autoionization of Water .txt", "text": "And now this becomes very useful when I'm solving problems using PH and poh."}, {"title": "Intensive and Extensive Properties.txt", "text": "Hi."}, {"title": "Intensive and Extensive Properties.txt", "text": "Today we're going to talk about extensive properties, intensive properties, state functions of a system of interest."}, {"title": "Intensive and Extensive Properties.txt", "text": "OK?"}, {"title": "Intensive and Extensive Properties.txt", "text": "Before we talk about these guys, let's define what a system is."}, {"title": "Intensive and Extensive Properties.txt", "text": "A system is simply something that a person or a scientist or researcher wants to study."}, {"title": "Intensive and Extensive Properties.txt", "text": "It's the object of interest, okay?"}, {"title": "Intensive and Extensive Properties.txt", "text": "And the object could be as simple as the eraser."}, {"title": "Intensive and Extensive Properties.txt", "text": "It could be this marker, it could be this whiteboard, it could be me, it could be the room, the building, this system."}, {"title": "Intensive and Extensive Properties.txt", "text": "For example, if we chose this eraser to be the system has certain properties, it has a certain weight, it has a certain mass, it has a certain volume, certain density, certain pressure, certain height, length and width."}, {"title": "Intensive and Extensive Properties.txt", "text": "It has certain properties that are used to quantify this system."}, {"title": "Intensive and Extensive Properties.txt", "text": "And these properties, if you list them all in order, could be subdivided into two categories extensive properties and intensive properties."}, {"title": "Intensive and Extensive Properties.txt", "text": "Okay?"}, {"title": "Intensive and Extensive Properties.txt", "text": "Extensive properties are those properties that depend on size and intensive properties do not depend on size."}, {"title": "Intensive and Extensive Properties.txt", "text": "So let's go through the examples."}, {"title": "Intensive and Extensive Properties.txt", "text": "Extensive properties, let's talk about mass."}, {"title": "Intensive and Extensive Properties.txt", "text": "So this eraser has a certain mass, okay?"}, {"title": "Intensive and Extensive Properties.txt", "text": "And what happens to the mass if you double the size of this eraser?"}, {"title": "Intensive and Extensive Properties.txt", "text": "Well, the mass would also double."}, {"title": "Intensive and Extensive Properties.txt", "text": "Suppose you add or you stack a second eraser on top of this eraser, what will happen to the mass?"}, {"title": "Intensive and Extensive Properties.txt", "text": "It will double."}, {"title": "Intensive and Extensive Properties.txt", "text": "How about the force or the weight felt by a scale?"}, {"title": "Intensive and Extensive Properties.txt", "text": "Right?"}, {"title": "Intensive and Extensive Properties.txt", "text": "If you take this eraser and you weight it, you get one force."}, {"title": "Intensive and Extensive Properties.txt", "text": "If you weight this or if you weigh two erasers, you will get a force twice the size of the original."}, {"title": "Intensive and Extensive Properties.txt", "text": "So force is also dependent on size, volume as well."}, {"title": "Intensive and Extensive Properties.txt", "text": "Volume is pretty intuitive."}, {"title": "Intensive and Extensive Properties.txt", "text": "If you increase the size of this twice the size, the volume will also increase."}, {"title": "Intensive and Extensive Properties.txt", "text": "Same with area, same with length, width and height, right?"}, {"title": "Intensive and Extensive Properties.txt", "text": "If you take this eraser, if you stack another eraser on top of it, the height will increase."}, {"title": "Intensive and Extensive Properties.txt", "text": "So increase in size increases height."}, {"title": "Intensive and Extensive Properties.txt", "text": "How about moles?"}, {"title": "Intensive and Extensive Properties.txt", "text": "Well, this is composed of certain bonds, certain atoms that are bonded together, right?"}, {"title": "Intensive and Extensive Properties.txt", "text": "Covalently well, number of moles."}, {"title": "Intensive and Extensive Properties.txt", "text": "Suppose this is composed of a certain number of moles."}, {"title": "Intensive and Extensive Properties.txt", "text": "Suppose it's x number of moles."}, {"title": "Intensive and Extensive Properties.txt", "text": "You take a second eraser identical to this one, stack it on top of this one, and what will you get?"}, {"title": "Intensive and Extensive Properties.txt", "text": "You will get an eraser with x number of moles."}, {"title": "Intensive and Extensive Properties.txt", "text": "A second eraser with x number of moles."}, {"title": "Intensive and Extensive Properties.txt", "text": "The result is two x number of moles."}, {"title": "Intensive and Extensive Properties.txt", "text": "So increasing this size or this system to twice its size increases the number of moles to twice number of original moles, number of moles increases."}, {"title": "Intensive and Extensive Properties.txt", "text": "And remember, internal energy depends on the number of moles of the atom."}, {"title": "Intensive and Extensive Properties.txt", "text": "So if the number of atoms increases or the number of moles increase, the internal energy also increases."}, {"title": "Intensive and Extensive Properties.txt", "text": "Okay?"}, {"title": "Intensive and Extensive Properties.txt", "text": "So all these guys, all these properties are properties that can be used to describe the system of interest, to quantify it depends on the size of the system."}, {"title": "Intensive and Extensive Properties.txt", "text": "Increasing the size of this increases these properties."}, {"title": "Intensive and Extensive Properties.txt", "text": "How about intensive properties?"}, {"title": "Intensive and Extensive Properties.txt", "text": "Earlier we said instant properties are those properties that do not depend on the size."}, {"title": "Intensive and Extensive Properties.txt", "text": "They're independent."}, {"title": "Intensive and Extensive Properties.txt", "text": "So let's see why temperature is independent property."}, {"title": "Intensive and Extensive Properties.txt", "text": "So let's not use this as an example, but let's use something more intuitive."}, {"title": "Intensive and Extensive Properties.txt", "text": "Let's use our human body, okay?"}, {"title": "Intensive and Extensive Properties.txt", "text": "So let's take three different individuals."}, {"title": "Intensive and Extensive Properties.txt", "text": "Let's take a baby, let's take myself and let's take our seven foot player, okay?"}, {"title": "Intensive and Extensive Properties.txt", "text": "Seven foot basketball player."}, {"title": "Intensive and Extensive Properties.txt", "text": "We are all different in size, right?"}, {"title": "Intensive and Extensive Properties.txt", "text": "The baby is really small on average."}, {"title": "Intensive and Extensive Properties.txt", "text": "And then the height of the basketball player is really big."}, {"title": "Intensive and Extensive Properties.txt", "text": "So there's clearly a difference in size."}, {"title": "Intensive and Extensive Properties.txt", "text": "So we're all going to have different masses, different weights, different volumes, compose a different number of spells or moles, have a different area, have a different length or height width, have different internal energy."}, {"title": "Intensive and Extensive Properties.txt", "text": "But our temperature will stay the same."}, {"title": "Intensive and Extensive Properties.txt", "text": "If you check using a thermometer, the baby will have approximately 37 Celsius or 98 Fahrenheit."}, {"title": "Intensive and Extensive Properties.txt", "text": "I will have that same temperature and so will that giant dusky clip."}, {"title": "Intensive and Extensive Properties.txt", "text": "So the temperature remains the same the same way that if you return to this system, that might be less intuitive, but still remains true that the temperature of this, regardless of size, remains the same."}, {"title": "Intensive and Extensive Properties.txt", "text": "How about pressure?"}, {"title": "Intensive and Extensive Properties.txt", "text": "Well, pressure from chemistry or from physics, we know to be force over area, correct?"}, {"title": "Intensive and Extensive Properties.txt", "text": "And the force and the area we saw are both extensive properties."}, {"title": "Intensive and Extensive Properties.txt", "text": "In fact, it's true that if we take the ratio of two extensive properties or if we divide an extensive property by second extensive property, what we get is an incentive property."}, {"title": "Intensive and Extensive Properties.txt", "text": "That always holds true."}, {"title": "Intensive and Extensive Properties.txt", "text": "And let's see why."}, {"title": "Intensive and Extensive Properties.txt", "text": "Well, priced is just a ratio, right?"}, {"title": "Intensive and Extensive Properties.txt", "text": "So if we increase this by, say, two, this increases by two and these guys cancel out."}, {"title": "Intensive and Extensive Properties.txt", "text": "So no matter what, we increase this by, say by three, by four, by five, by six and so on, this will increase by a similar increment."}, {"title": "Intensive and Extensive Properties.txt", "text": "Meaning that you could cancel these guys out and you get the same ratio over and over and over."}, {"title": "Intensive and Extensive Properties.txt", "text": "So pressure always stays the same no matter of size."}, {"title": "Intensive and Extensive Properties.txt", "text": "Density stays the same for the same reason."}, {"title": "Intensive and Extensive Properties.txt", "text": "Because density is mass over volume, it's also a ratio of two extensive properties."}, {"title": "Intensive and Extensive Properties.txt", "text": "And so the result is an intensive property."}, {"title": "Intensive and Extensive Properties.txt", "text": "So let's talk about what state functions are."}, {"title": "Intensive and Extensive Properties.txt", "text": "So state functions are also properties of a system."}, {"title": "Intensive and Extensive Properties.txt", "text": "They're either excessive properties or incentive properties."}, {"title": "Intensive and Extensive Properties.txt", "text": "And they're basically values that do not change regardless of the path taken, okay?"}, {"title": "Intensive and Extensive Properties.txt", "text": "These properties only depend on the current state of the system."}, {"title": "Intensive and Extensive Properties.txt", "text": "Okay, let's take this as our example again, the eraser."}, {"title": "Intensive and Extensive Properties.txt", "text": "And let's think about how it was made."}, {"title": "Intensive and Extensive Properties.txt", "text": "So it was made in different factories across the world, right?"}, {"title": "Intensive and Extensive Properties.txt", "text": "Suppose Factory A is in China."}, {"title": "Intensive and Extensive Properties.txt", "text": "Factory B is in California."}, {"title": "Intensive and Extensive Properties.txt", "text": "And suppose that these factories have different methods of creating these erasers."}, {"title": "Intensive and Extensive Properties.txt", "text": "Okay?"}, {"title": "Intensive and Extensive Properties.txt", "text": "Suppose a factory A divides this in half or creates two erasers, and then it combines them in some machine, okay?"}, {"title": "Intensive and Extensive Properties.txt", "text": "And then suppose that the factory in California takes five different small pieces of the eraser and then combines them at the end, okay?"}, {"title": "Intensive and Extensive Properties.txt", "text": "The end result is the same."}, {"title": "Intensive and Extensive Properties.txt", "text": "The end result is an erasure approximately the size, this weight, this volume, the same dimensions."}, {"title": "Intensive and Extensive Properties.txt", "text": "The pathway by which it was created differs from factory A and factory B."}, {"title": "Intensive and Extensive Properties.txt", "text": "But the end result is the same."}, {"title": "Intensive and Extensive Properties.txt", "text": "So let's talk about mass and why."}, {"title": "Intensive and Extensive Properties.txt", "text": "Mass is a state function or a function or a property that does not depend on the pathway taken."}, {"title": "Intensive and Extensive Properties.txt", "text": "It only depends on the system at hand, the current system at hand."}, {"title": "Intensive and Extensive Properties.txt", "text": "So let's take our eraser again, okay?"}, {"title": "Intensive and Extensive Properties.txt", "text": "This is our eraser."}, {"title": "Intensive and Extensive Properties.txt", "text": "And let's say our eraser is 500 grams, okay?"}, {"title": "Intensive and Extensive Properties.txt", "text": "So that's its mass."}, {"title": "Intensive and Extensive Properties.txt", "text": "Suppose once again, factory A takes a 250 grams part and a 250 grams part, okay?"}, {"title": "Intensive and Extensive Properties.txt", "text": "And suppose that it uses glue."}, {"title": "Intensive and Extensive Properties.txt", "text": "It glues this thing and it creates this eraser, okay?"}, {"title": "Intensive and Extensive Properties.txt", "text": "That's how factory A makes it."}, {"title": "Intensive and Extensive Properties.txt", "text": "What is the end result?"}, {"title": "Intensive and Extensive Properties.txt", "text": "The end result is a 500 grams eraser."}, {"title": "Intensive and Extensive Properties.txt", "text": "Now suppose factory B makes the eraser, but it makes it different."}, {"title": "Intensive and Extensive Properties.txt", "text": "It makes it in sections of 100 grams, okay?"}, {"title": "Intensive and Extensive Properties.txt", "text": "So it basically takes five sections of 100 grams each and glues them together and it forms our 500 grams eraser, right?"}, {"title": "Intensive and Extensive Properties.txt", "text": "The end result is also a 500 grams eraser."}, {"title": "Intensive and Extensive Properties.txt", "text": "So the end result, the end mass of the eraser is identical."}, {"title": "Intensive and Extensive Properties.txt", "text": "It's the same matter what path taken."}, {"title": "Intensive and Extensive Properties.txt", "text": "No matter how you create their eraser, if you took 100 grams and put them together, and you put 250 grams and put them together, the pathways differ."}, {"title": "Intensive and Extensive Properties.txt", "text": "But the actual the final result was the same."}, {"title": "Intensive and Extensive Properties.txt", "text": "And that's why mass is a state function."}, {"title": "Intensive and Extensive Properties.txt", "text": "Because it's independent of the pathway taken to get that final."}, {"title": "Base Ionization Constant .txt", "text": "In this lecture we're going to talk about ionization constants of basis known as KB."}, {"title": "Base Ionization Constant .txt", "text": "But before we talk about this guy, we really have to understand these two components."}, {"title": "Base Ionization Constant .txt", "text": "So, if you have already done so, watch the video below on Otoinisation of water and Annetzation of acids."}, {"title": "Base Ionization Constant .txt", "text": "Now, so let's begin."}, {"title": "Base Ionization Constant .txt", "text": "Let's suppose we have some hypothetical base, let's call it A."}, {"title": "Base Ionization Constant .txt", "text": "And this base in aqueous state reacts with a single water molecule in a liquid state."}, {"title": "Base Ionization Constant .txt", "text": "So what will happen?"}, {"title": "Base Ionization Constant .txt", "text": "Well, our base will act as a base trying to take that ho away from our acid, namely our water molecule."}, {"title": "Base Ionization Constant .txt", "text": "And these guys will create a conjugate acid ha and a conjugate base, our hydroxide molecule."}, {"title": "Base Ionization Constant .txt", "text": "Both guys are in aqueous state."}, {"title": "Base Ionization Constant .txt", "text": "The same way we wrote equilibrium expressions for acid and for water, we can also write equilibrium expressions for bases as well."}, {"title": "Base Ionization Constant .txt", "text": "Except now we replace our ka and Kw with KB or Dionization constant for our base."}, {"title": "Base Ionization Constant .txt", "text": "So KB is equal to the conjugate acid or the concentration of the conjugate acid times the concentration of our hydroxide divided by our conjugate base."}, {"title": "Base Ionization Constant .txt", "text": "So, in terms of this reaction, it's this guy."}, {"title": "Base Ionization Constant .txt", "text": "The concentration of this guy times the concentration of this guy."}, {"title": "Base Ionization Constant .txt", "text": "So our products go to the denominator over our conjugate base, this guy."}, {"title": "Base Ionization Constant .txt", "text": "So our reactants go on the bottom."}, {"title": "Base Ionization Constant .txt", "text": "Our products go to the top just like they would for acids and for water."}, {"title": "Base Ionization Constant .txt", "text": "Now, the same way we spoke about ka's being ratios in terms of ionization of acids, we could also talk about KBS or ionization of bases being ratios."}, {"title": "Base Ionization Constant .txt", "text": "Their ratios of amount of product formed over the amount of react is left."}, {"title": "Base Ionization Constant .txt", "text": "So that means the greater our value for KB is, the more favorable our reaction is this way."}, {"title": "Base Ionization Constant .txt", "text": "And this means the better or stronger our base is."}, {"title": "Base Ionization Constant .txt", "text": "If this guy is greater than one, we can say that it's a strong base."}, {"title": "Base Ionization Constant .txt", "text": "If it's less than one, it's a weak base."}, {"title": "Base Ionization Constant .txt", "text": "And that's because if it's less than one, that means amount of reacting left is much greater than the amount of product formed."}, {"title": "Base Ionization Constant .txt", "text": "And that means this guy hasn't really reacted yet."}, {"title": "Base Ionization Constant .txt", "text": "And that's because our base is a poor base."}, {"title": "Base Ionization Constant .txt", "text": "It's not very good at what it does."}, {"title": "Base Ionization Constant .txt", "text": "It's not very good at taking that H away from that acid."}, {"title": "Base Ionization Constant .txt", "text": "So once again, if a KB is high, then that means it's a good base."}, {"title": "Base Ionization Constant .txt", "text": "If it's low, it's a bad base."}, {"title": "Base Ionization Constant .txt", "text": "Now, let's see what happens when we multiply ka times KB or Dionization cost of assets times Dionization constant basis."}, {"title": "Base Ionization Constant .txt", "text": "Well, let's rewrite Ka."}, {"title": "Base Ionization Constant .txt", "text": "Or let's first rewrite KB."}, {"title": "Base Ionization Constant .txt", "text": "Well, KB is simply this whole guy here."}, {"title": "Base Ionization Constant .txt", "text": "So Ha multiplied by oh of the concentration divided by concentration of eight."}, {"title": "Base Ionization Constant .txt", "text": "Now, if we go back to the video for ionization of acids, which you'll find right here, you'll notice that ka is equal to this guy times the hydronium concentration divided by Ha or the concentration of ha."}, {"title": "Base Ionization Constant .txt", "text": "Now let's see what happens."}, {"title": "Base Ionization Constant .txt", "text": "Well, this guy and this guy cancel, right?"}, {"title": "Base Ionization Constant .txt", "text": "So this guy not the bad marker."}, {"title": "Base Ionization Constant .txt", "text": "This guy cancels, and this guy cancels."}, {"title": "Base Ionization Constant .txt", "text": "Also this guy cancels, and this guy cancels."}, {"title": "Base Ionization Constant .txt", "text": "So we're left with hydronium concentration times the hydroxide concentration."}, {"title": "Base Ionization Constant .txt", "text": "And if you go back to the video for Autoinization of War, which you'll find right here, you'll see that this guy simply equals kw."}, {"title": "Base Ionization Constant .txt", "text": "So we see that when we multiply ka times KB, what we get is kw."}, {"title": "Base Ionization Constant .txt", "text": "So this is an important relation."}, {"title": "Base Ionization Constant .txt", "text": "Now, what happens if we take the log of both sides?"}, {"title": "Base Ionization Constant .txt", "text": "Well, if we take the log of both sides, we get PKW is equal to PKA plus PKB."}, {"title": "Base Ionization Constant .txt", "text": "Remember?"}, {"title": "Base Ionization Constant .txt", "text": "According to the laws of logs, when we take the log of this, this becomes addition, right?"}, {"title": "Base Ionization Constant .txt", "text": "And this equals 14."}, {"title": "Base Ionization Constant .txt", "text": "Now, if you're not sure where this came from, how I got from this point to this point, check out the video below."}, {"title": "Base Ionization Constant .txt", "text": "At the end of the video, I talk about the laws of logs."}, {"title": "Base Ionization Constant .txt", "text": "And I show you how I go from this to this guy, or something similar to this to this guy."}, {"title": "Base Ionization Constant .txt", "text": "So our end result is that 14 equals PKA plus PKB."}, {"title": "Naming of Alkanes.txt", "text": "So naming alkanes can sometimes be complicated."}, {"title": "Naming of Alkanes.txt", "text": "So let's look at a few important rules that we have to keep in mind whenever we're naming alkanes."}, {"title": "Naming of Alkanes.txt", "text": "Rule number one, find the longest straight chain of carbons."}, {"title": "Naming of Alkanes.txt", "text": "So, to demonstrate this rule, let's look at a few examples."}, {"title": "Naming of Alkanes.txt", "text": "So, let's create an alkane, and then then let's try to find the longest straight chain of carbons on that alkane."}, {"title": "Naming of Alkanes.txt", "text": "So let's suppose we have an alkane that looks like that."}, {"title": "Naming of Alkanes.txt", "text": "Okay, so we want to find the longest straight chain of carbons."}, {"title": "Naming of Alkanes.txt", "text": "So let's begin counting our carbons."}, {"title": "Naming of Alkanes.txt", "text": "So one carbon, two carbon, three carbon."}, {"title": "Naming of Alkanes.txt", "text": "Now, since we want to find the longest straight chain of carbons, we have to choose in which direction we want to go to find that longer straight chain."}, {"title": "Naming of Alkanes.txt", "text": "Well, if we choose this way, we get four."}, {"title": "Naming of Alkanes.txt", "text": "If we choose this way, we get five."}, {"title": "Naming of Alkanes.txt", "text": "So we go this way, four and five."}, {"title": "Naming of Alkanes.txt", "text": "So, this is the longest straight chain of carbons, and this is called the carbon backbone."}, {"title": "Naming of Alkanes.txt", "text": "And we name our alkane."}, {"title": "Naming of Alkanes.txt", "text": "The last part of our name for the alkane should refer to this carbon backbone."}, {"title": "Naming of Alkanes.txt", "text": "So that means we'll have a pentane."}, {"title": "Naming of Alkanes.txt", "text": "Now, we're not done with naming this molecule."}, {"title": "Naming of Alkanes.txt", "text": "We'll come back to it after rule number two."}, {"title": "Naming of Alkanes.txt", "text": "So penth means five."}, {"title": "Naming of Alkanes.txt", "text": "Aim means it's an alkane."}, {"title": "Naming of Alkanes.txt", "text": "So let's come up with a second alkane."}, {"title": "Naming of Alkanes.txt", "text": "So, now let's suppose we have the following."}, {"title": "Naming of Alkanes.txt", "text": "So, let's say we have one more carbon."}, {"title": "Naming of Alkanes.txt", "text": "So let's begin naming in the same manner."}, {"title": "Naming of Alkanes.txt", "text": "So, one, two, three."}, {"title": "Naming of Alkanes.txt", "text": "Now, we want to go this way."}, {"title": "Naming of Alkanes.txt", "text": "Why?"}, {"title": "Naming of Alkanes.txt", "text": "Well, because if we go this way, we'll end at four."}, {"title": "Naming of Alkanes.txt", "text": "If we go this way, we'll end at 6545 and six."}, {"title": "Naming of Alkanes.txt", "text": "So, once again, our longest carbon backbone has six."}, {"title": "Naming of Alkanes.txt", "text": "So that means we write Hexane."}, {"title": "Naming of Alkanes.txt", "text": "Hex simply means six, and A means it's an alkane."}, {"title": "Naming of Alkanes.txt", "text": "So let's get another alkane in."}, {"title": "Naming of Alkanes.txt", "text": "So let's say we have this one."}, {"title": "Naming of Alkanes.txt", "text": "So let's say we have the following alkane."}, {"title": "Naming of Alkanes.txt", "text": "So, once again, let's begin labeling our carbons numbering our carbon."}, {"title": "Naming of Alkanes.txt", "text": "So one carbon, two, three, four."}, {"title": "Naming of Alkanes.txt", "text": "If we go up, we end at six."}, {"title": "Naming of Alkanes.txt", "text": "If we go sideways, we end at seven."}, {"title": "Naming of Alkanes.txt", "text": "So we choose sideways."}, {"title": "Naming of Alkanes.txt", "text": "So, our longest carbon backbone has seven carbons, and so we name it Heptane."}, {"title": "Naming of Alkanes.txt", "text": "hept means seven."}, {"title": "Naming of Alkanes.txt", "text": "A means how can."}, {"title": "Naming of Alkanes.txt", "text": "Now, once again, we're not done naming these guys."}, {"title": "Naming of Alkanes.txt", "text": "We'll come back to these guys after rule number two."}, {"title": "Naming of Alkanes.txt", "text": "So let's look at rule number two."}, {"title": "Naming of Alkanes.txt", "text": "In substituted alkanes, the substituent is given a number based on the position on that carbon backbone, and the number value should be as low as possible."}, {"title": "Naming of Alkanes.txt", "text": "So let's go to example number one."}, {"title": "Naming of Alkanes.txt", "text": "So, our substituent is this methyl group."}, {"title": "Naming of Alkanes.txt", "text": "Now, if we start from this side, we go one, two, three."}, {"title": "Naming of Alkanes.txt", "text": "So, our methyl is on the third position of the carbon backbone."}, {"title": "Naming of Alkanes.txt", "text": "If we start from this side, it's also on the third."}, {"title": "Naming of Alkanes.txt", "text": "So this has symmetry."}, {"title": "Naming of Alkanes.txt", "text": "And so we simply write three methyl pentane."}, {"title": "Naming of Alkanes.txt", "text": "Example number two."}, {"title": "Naming of Alkanes.txt", "text": "Now in this one, it's a bit more tricky because this doesn't have symmetry the same way that this one has."}, {"title": "Naming of Alkanes.txt", "text": "So if we begin on this side of our backbone, we go one, two, three."}, {"title": "Naming of Alkanes.txt", "text": "If we begin on that side, we get 1234."}, {"title": "Naming of Alkanes.txt", "text": "Remember, we want the lowest possible number, so we should start from this way."}, {"title": "Naming of Alkanes.txt", "text": "And that's exactly why I began labeling on this side of the chain of carbons."}, {"title": "Naming of Alkanes.txt", "text": "So since we have a methyl group, we have three methylhexane."}, {"title": "Naming of Alkanes.txt", "text": "And finally, the last example, like this one, also has symmetry down the middle."}, {"title": "Naming of Alkanes.txt", "text": "It doesn't matter if we begin here or here, 1234-1234."}, {"title": "Naming of Alkanes.txt", "text": "So we write four, but now we have not a methyl, but an ethyl, because we have two carbons."}, {"title": "Naming of Alkanes.txt", "text": "So that concludes these examples."}, {"title": "Naming of Alkanes.txt", "text": "Let's go to these two examples."}, {"title": "Naming of Alkanes.txt", "text": "So once again, according to rule number one, we want to find the longest chain of carbon."}, {"title": "Naming of Alkanes.txt", "text": "So we can either have 1234 or 1234."}, {"title": "Naming of Alkanes.txt", "text": "Now we want the lowest value for our substituent."}, {"title": "Naming of Alkanes.txt", "text": "So we begin here, 1234."}, {"title": "Naming of Alkanes.txt", "text": "So 1234, and let's name them."}, {"title": "Naming of Alkanes.txt", "text": "Now, since it has four carbons, that means our backbone is butane."}, {"title": "Naming of Alkanes.txt", "text": "So we have butane for the backbone."}, {"title": "Naming of Alkanes.txt", "text": "And then our second position, position two is a bromine."}, {"title": "Naming of Alkanes.txt", "text": "So we name it bromo."}, {"title": "Naming of Alkanes.txt", "text": "Bromo is short for bromine."}, {"title": "Naming of Alkanes.txt", "text": "Now let's look at the the second one."}, {"title": "Naming of Alkanes.txt", "text": "Once again, this has symmetry."}, {"title": "Naming of Alkanes.txt", "text": "It doesn't matter if we begin here or here."}, {"title": "Naming of Alkanes.txt", "text": "So 1234 and 1234."}, {"title": "Naming of Alkanes.txt", "text": "Either way, this is the fourth position on our carbon backbone."}, {"title": "Naming of Alkanes.txt", "text": "So let's begin 123456 and seven."}, {"title": "Naming of Alkanes.txt", "text": "So it's a heptane and it's a four position substituted."}, {"title": "Naming of Alkanes.txt", "text": "So that means four chloroheptane, four chlorohessane."}, {"title": "Naming of Alkanes.txt", "text": "Okay, let's go to rule number three."}, {"title": "Naming of Alkanes.txt", "text": "In multisubstituted alkanes, substituents are ordered alphabetically, and identical substituents receive prefix, die, try, tetra, et cetera."}, {"title": "Naming of Alkanes.txt", "text": "So let's look at the last three examples."}, {"title": "Naming of Alkanes.txt", "text": "So once again, we have to keep these two rules in mind."}, {"title": "Naming of Alkanes.txt", "text": "Our first goal is to find the longest straight chain of carbon, so 12345 or 123456."}, {"title": "Naming of Alkanes.txt", "text": "So we choose to go this way."}, {"title": "Naming of Alkanes.txt", "text": "And remember, since we have two substituents, we have a bromo and a methyl."}, {"title": "Naming of Alkanes.txt", "text": "We want to follow an alphabetical rule."}, {"title": "Naming of Alkanes.txt", "text": "So that means since B comes before AMA, we have to start this way."}, {"title": "Naming of Alkanes.txt", "text": "So 1234, so 123456."}, {"title": "Naming of Alkanes.txt", "text": "Okay, so we have a hexane."}, {"title": "Naming of Alkanes.txt", "text": "So our backbone is hexane, and we have three bromo and four methyl."}, {"title": "Naming of Alkanes.txt", "text": "I'm not going to have room, but this should be methyl."}, {"title": "Naming of Alkanes.txt", "text": "Okay, let's go to this."}, {"title": "Naming of Alkanes.txt", "text": "11234 or 1234."}, {"title": "Naming of Alkanes.txt", "text": "Which way do we go?"}, {"title": "Naming of Alkanes.txt", "text": "Well, once again, we want the alphabetical rule."}, {"title": "Naming of Alkanes.txt", "text": "So since B comes before C, that means we start here."}, {"title": "Naming of Alkanes.txt", "text": "So let's start on that side."}, {"title": "Naming of Alkanes.txt", "text": "We have 1234, and so we're going to have two bromo, three chloro, and then since we have four chain carbon backbone, we have butane."}, {"title": "Naming of Alkanes.txt", "text": "Okay, so now let's look at the final molecule."}, {"title": "Naming of Alkanes.txt", "text": "In this final molecule, we have two identical substituents, and that means we're going to want to use a diprefix."}, {"title": "Naming of Alkanes.txt", "text": "So this is a terriblel substituent."}, {"title": "Naming of Alkanes.txt", "text": "So let's find our longest straight chain."}, {"title": "Naming of Alkanes.txt", "text": "So 1234-5678."}, {"title": "Naming of Alkanes.txt", "text": "So that means we're going to have an octane."}, {"title": "Naming of Alkanes.txt", "text": "So let's label 123-4567 and eight."}, {"title": "Naming of Alkanes.txt", "text": "So that means we're going to have an octane carbon backbone and we're going to have dye."}, {"title": "Naming of Alkanes.txt", "text": "So dye meaning two TURPE, butyl octane."}, {"title": "Naming of Alkanes.txt", "text": "And notice this is not done because we want to actually label on which carbon are our two substituents are located."}, {"title": "Naming of Alkanes.txt", "text": "So four and five."}, {"title": "Naming of Alkanes.txt", "text": "So that means we're going to have four, five dirtbutyl octane."}, {"title": "Naming of Alkanes Examples .txt", "text": "In this lecture, we're going to continue naming our alkators."}, {"title": "Naming of Alkanes Examples .txt", "text": "So here we have five examples."}, {"title": "Naming of Alkanes Examples .txt", "text": "Let's begin with example number one."}, {"title": "Naming of Alkanes Examples .txt", "text": "So first we want to find the longest possible carbon backbone, so 1234."}, {"title": "Naming of Alkanes Examples .txt", "text": "Or we can also have 1234."}, {"title": "Naming of Alkanes Examples .txt", "text": "Either way, we have a four carbon backbone."}, {"title": "Naming of Alkanes Examples .txt", "text": "So that means we're dealing with butane."}, {"title": "Naming of Alkanes Examples .txt", "text": "Now, which way do we want to go starting for this carbon or this carbon?"}, {"title": "Naming of Alkanes Examples .txt", "text": "Well, remember, our substituents should have the lowest possible number."}, {"title": "Naming of Alkanes Examples .txt", "text": "So that means we begin on this end."}, {"title": "Naming of Alkanes Examples .txt", "text": "So 1234."}, {"title": "Naming of Alkanes Examples .txt", "text": "And that means we're going to name it."}, {"title": "Naming of Alkanes Examples .txt", "text": "So our substituents are both located on the second position."}, {"title": "Naming of Alkanes Examples .txt", "text": "That means we have two, we have bromo, so dibromo."}, {"title": "Naming of Alkanes Examples .txt", "text": "And then butane."}, {"title": "Naming of Alkanes Examples .txt", "text": "So 22 simply means our two bromos are located on the second position."}, {"title": "Naming of Alkanes Examples .txt", "text": "And our chain is a butane 1234."}, {"title": "Naming of Alkanes Examples .txt", "text": "So let's look at the second example."}, {"title": "Naming of Alkanes Examples .txt", "text": "So once again, we want to find the longest possible carbon backbone."}, {"title": "Naming of Alkanes Examples .txt", "text": "Carbon chain, 1234 or 12345."}, {"title": "Naming of Alkanes Examples .txt", "text": "Now, since this guy is symmetrical, it doesn't matter if we start from this end or this end."}, {"title": "Naming of Alkanes Examples .txt", "text": "So let's begin from this end."}, {"title": "Naming of Alkanes Examples .txt", "text": "12345"}, {"title": "Naming of Alkanes Examples .txt", "text": "And our substituents are both on the third carbon."}, {"title": "Naming of Alkanes Examples .txt", "text": "So that means we're going to have three three dimethyl."}, {"title": "Naming of Alkanes Examples .txt", "text": "They're both methyl compounds, and we have five."}, {"title": "Naming of Alkanes Examples .txt", "text": "So that means we have pentane."}, {"title": "Naming of Alkanes Examples .txt", "text": "Let's look at a third example."}, {"title": "Naming of Alkanes Examples .txt", "text": "So once again, longest possible carbon backbone."}, {"title": "Naming of Alkanes Examples .txt", "text": "One, two, three, or one, two, three, or one, two, three."}, {"title": "Naming of Alkanes Examples .txt", "text": "Doesn't matter which way we go."}, {"title": "Naming of Alkanes Examples .txt", "text": "So let's go straight across."}, {"title": "Naming of Alkanes Examples .txt", "text": "One, two, three."}, {"title": "Naming of Alkanes Examples .txt", "text": "So three carbon backbone."}, {"title": "Naming of Alkanes Examples .txt", "text": "That means we're dealing with a propane."}, {"title": "Naming of Alkanes Examples .txt", "text": "And on the second physician, we have two methyl groups."}, {"title": "Naming of Alkanes Examples .txt", "text": "So we have two two dimethyl propane."}, {"title": "Naming of Alkanes Examples .txt", "text": "Let's look at the fourth example."}, {"title": "Naming of Alkanes Examples .txt", "text": "So here we have a very long carbon backbone."}, {"title": "Naming of Alkanes Examples .txt", "text": "So we can either begin counting this way or this way or this way."}, {"title": "Naming of Alkanes Examples .txt", "text": "So we can say 123-45-6789 or 1234-5678 910."}, {"title": "Naming of Alkanes Examples .txt", "text": "So it looks like if we go along this carbon backbone, we're going to have the longest carbon backbone."}, {"title": "Naming of Alkanes Examples .txt", "text": "So we can either start from this end and go all the way down, or from this end and go all the way down."}, {"title": "Naming of Alkanes Examples .txt", "text": "Since we want our substituent to have the lowest possible number, we should probably start to this end."}, {"title": "Naming of Alkanes Examples .txt", "text": "And so let's start labeling or numbering."}, {"title": "Naming of Alkanes Examples .txt", "text": "1234-5678, 910."}, {"title": "Naming of Alkanes Examples .txt", "text": "Okay, so that means we have ten, so that's decay."}, {"title": "Naming of Alkanes Examples .txt", "text": "And we have on the third carbon, we have so three methyl decay."}, {"title": "Naming of Alkanes Examples .txt", "text": "All right, so let's look at the final example."}, {"title": "Naming of Alkanes Examples .txt", "text": "So here we can start from either this position, this position, this guy, this guy, or this guy."}, {"title": "Naming of Alkanes Examples .txt", "text": "So if we start from this position, we have 1234-561-2345 or 123456, or we can have 123-4567."}, {"title": "Naming of Alkanes Examples .txt", "text": "So if we start from this end or this end, it looks like we get the longest possible carbon backbone."}, {"title": "Naming of Alkanes Examples .txt", "text": "So let's begin from this end."}, {"title": "Naming of Alkanes Examples .txt", "text": "So 123-4567."}, {"title": "Naming of Alkanes Examples .txt", "text": "Okay, and now these guys are our substituents."}, {"title": "Naming of Alkanes Examples .txt", "text": "So we have three substituents."}, {"title": "Naming of Alkanes Examples .txt", "text": "Two of them are identical, so they're methyl."}, {"title": "Naming of Alkanes Examples .txt", "text": "And one of them is ethyl."}, {"title": "Naming of Alkanes Examples .txt", "text": "So ethyl comes before methyl because E comes before M. So that means this guy will become will come before these two guys."}, {"title": "Naming of Alkanes Examples .txt", "text": "So let's first make sure we have seven."}, {"title": "Naming of Alkanes Examples .txt", "text": "So that means we have Heftane."}, {"title": "Naming of Alkanes Examples .txt", "text": "And we're going to start with one, two so four."}, {"title": "Naming of Alkanes Examples .txt", "text": "So we're going to have poor Ethyl."}, {"title": "Naming of Alkanes Examples .txt", "text": "Then we're going to have two, three, so two, three, dimethyl."}, {"title": "Naming of Alkanes Examples .txt", "text": "Four, Ethyl."}, {"title": "Naming of Alkanes Examples .txt", "text": "Two, three, dimethyl."}, {"title": "Naming of Alkanes Examples .txt", "text": "Heptane."}, {"title": "Naming of Alkanes Examples .txt", "text": "So we have our seven chain carbon backbone, two identical 23 dimethyls, and we have one ethyl."}, {"title": "Naming of Alkanes Examples .txt", "text": "And this guy comes before the two guys because E comes before M in the alphabet."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "So in this lecture, I'd like to talk about ionic bonds."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "But before we understand what ionic bonds are, let's talk about electron affinity as well as ionization energy."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "So here we have parts of our periodic table."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "So we have hydrogen, lithium, sodium."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "We have beryllium and magnesium."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "And this side we have have three noble gases fluorine, fluorine."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "And we have oxygen and sulfur."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "So let's look at what ionization energy of an atom is."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "Now, according to my definition, ionization energy is the energy required to remove an electron from an atom."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "So to demonstrate that, we're going to use the following Beryllium atom."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "So Beryllium has 12344 Protons."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "So there are four protons within the nucleus, also four neutrons."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "And since our neutral atom has a charge of zero, that means if we have four protons, we must have four electrons."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "So two electrons are placed into the one s orbital, and two electrons are placed into the two s orbital."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "So what this basically means is that in order to remove an electron from the outermost shell of my Beryllium atom, I must input energy."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "I must do work on my atom to take that electron away."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "So if I input enough energy, I will be able to pluck this outermost electron away to form the following Beryllium atom."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "Now, the number of protons is the same."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "Before, we have four protons, and now we have four protons."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "So that means that we still have a Beryllium atom."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "But since we took that electron away, that means that we're going to have a cation."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "We're going to have a net or an overall positive charge, because now we have four protons each have a plus one charge."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "But three electrons each have a negative one charge."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "So negative three plus four gives us a positive one charge."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "So this barrel has a plus one charge."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "And this is now a cat ion."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "Now, my next question is where did this energy go?"}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "Well, this energy actually went into my atom system, into this atom."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "So that means that this cation has more energy than this neutral species, neutral Beryllium atom."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "So that means because this has a lower energy, this is more stable than this cation."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "So once again, ionization energy is the energy required to take away an electron from a neutral, in this case, a neutral atom."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "So on my periodic table, the ionization energies are labeled with the green numerical value."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "So for example, for lithium, well, actually, let's take Beryllium."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "Beryllium requires 9.32\nenergy to take away this electron."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "And this energy goes in to this atom, forming this cation."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "This beryllium positively charged species."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "So now let's talk about electron affinity."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "Electron affinity is the energy that is released when an electron is added into my neutral or whatever type of atom."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "So now let's work backwards."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "Let's start from this case."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "Suppose we have this same positively charged Beryllium atom."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "And let's suppose I take an electron and I put the electron back into my outermost shell of this positively charged cation."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "What I get is the following beryllium atom."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "This is a neutral beryllium atom."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "Now, notice what happened here when we were going in this direction, I needed to input energy into my atom to take away that electron."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "And I said that this had a higher energy than this atom."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "So now we're working backwards."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "Now we have an atom, a beryllium atom that has a positive charge that is higher in energy than this product, than this neutral beryllium."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "So, in other words, when I take an electron, I put the electron inside my atom."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "Energy is released."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "And this energy is known as the electron affinity."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "Okay?"}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "And I labeled the electron affinity values with the brown color."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "So, for example, for Beryllium, beryllium has approximately a zero for electron affinity."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "So it's very, very small."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "And that basically means that Beryllium does not like to gain electrons."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "Okay."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "And this concept will become important in a second when we talk about ionic bonds."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "So let's see the conclusion."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "So atoms that have very low ionization energies."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "That basically means that electrons can be easily removed from those atoms."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "In other words, if we go to this table and we find atoms that have low ionization energies, for example, lithium lithium has 5.39 energy of ionization energy, while Fluorine, for example, has almost or has three times the value 17.42."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "That means that Lithium is much more prone to losing an electron than its fluorine."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "Same thing goes for sodium and same thing goes for chlorine."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "Chlorine has a higher value, higher ionization energy than sodium."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "And that means that sodium will be more likely to lose that electron compared to Chlorine."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "So let's go back to this guy."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "High electron affinity means that atoms will easily accept electrons."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "So if we go back to this table, we see that the electron affinity is labeled with the brown color."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "And notice that for flooring, electro affinity is 3.3, while the electron affinity for lithium is year zero 62."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "So because the electron affinity is much higher for fluorine, for chlorine, that means that these guys will be much more likely to gain an electron than will lithium or sodium."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "So let's see what ionic bonds are."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "So ionic bonds."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "Now atoms with very low ionization energies."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "That basically means that very small green values."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "So atoms on the left side of the periodic table will form bonds with atoms that have high electron affinities."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "So atoms that have very high brown numbers."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "So notice that fluorine, chlorine, oxygen and sulfur all have much higher values than brown values compared to this side, where we have zero point 62 for lithium, almost zero for both magnesium Beryllium and 00:55 for sodium."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "In other words, ionic bonds will only form between atoms found on the left side and atoms found on the right side of our periodic table."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "Now notice I didn't label anything for our noble gases."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "And that's because noble gases, as we know, have perfect electron configuration of electrons."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "And that means that they won't like to gain electrons."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "But they won't like to lose electrons either."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "So let's take an example."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "Let's see how an ionic bond is in fact formed and how are the atoms actually held."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "What forces hold these two atoms together in an ionic bond?"}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "So let's look at a neutral lithium atom."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "And let's look at a neutral fluorine atom."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "So we're taking one atom found on the left side and one atom found on the right side."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "So we're taking lithium, which has one, two, three protons."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "So three protons are in the nucleus, and that means if it's a mutual atom, it must have the same number of electrons."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "So three electrons."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "Two goes into the one s orbital and one goes into the two s orbital."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "So now we're taking fluorine."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "Fluorine has nine protons, so it must have nine electrons for it to be a mutual atom."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "So that means two go into the one s orbital, two goes into the two s orbital and five go into our two p orbital."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "Okay, so what happens?"}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "Well, we set an ionic bond is formed between atoms that have low ionization energies and high electron athenity energy."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "So low ionization energies."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "That means that very little energy is required to take this electron away from the outermost shell, while this flooring atom has a high electron affinity, which means that it is very likely that it will gain an electron."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "So what happens is one of these electrons found on the outermost shell is removed, and this electron is placed on the outermost shell in the two p orbital of the fluorine atom."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "And now what happens is, since this still has three protons, but it now has two electrons, this develops a positive charge."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "While this Fluorine atom, which Had Nine protons, nine Electrons, now has nine protons, ten electrons."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "So it develops a negative charge."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "And let's recall what Coulomb's Law tells us."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "So, from physics, we know that Coulomb's law simply states that constant K times charge one times charge two divided by the distance between the center of charges squared, gives us the force due to a charge on another charge."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "So here we have one charge species a cation."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "And here we have a second charge."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "Species an ion."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "And because these guys have now developed charges, different charges."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "These charges, positive or negative, will attract each other according to Coulomb's law."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "So we basically find the distance between their sensor charges."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "We plug that in here."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "We plug in the charges for both species."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "We multiply by the constant and we get the force that each atom feels due to the other atoms."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "So because there is charge now."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "There is a force between them."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "And this force holds them together."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "And this is known as an ionic bond."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "So, once again, to recap an Ionic bond is a bond between a count ion and an anion."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "And what that basically means that neutral charges or neutral atoms will not be able to form ionic bonds."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "In order to form an ionic bond, you have to have a positive atom and a negative atom."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "And the only way ionic bonds form is if you mix atoms from this side, from the left side of the periodic table with atoms on the right side of the periodic table."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "So one last important thing that I'd like to mention."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "So let's look at the electron configuration of these two atoms."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "Notice what happened."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "Remember we said that these guys, the noble gases, have perfect electron configurations."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "All their shells are filled."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "So let's look at what happened to the electro configuration of lithium and fluorine."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "Well, when lithium lost and lost an electron, right?"}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "When it lost an electron, it gained the electron configuration of helium, noble gas, while fluorine gained an electron and it formed the electron configuration of neon."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "Now, these guys still have the same amount of protons, so that means they are still the same same atom."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "But now they have very stable or perfect electron configurations."}, {"title": "Ionic Bonds, Ionization Energy, Electron Affinity.txt", "text": "Their electron configuration matches that of the noble gases."}, {"title": "Graham\u2019s Law .txt", "text": "So earlier we spoke about the concept of the kinetic theory of ideal gases."}, {"title": "Graham\u2019s Law .txt", "text": "And what this guy is is basically a bunch of assumptions made by scientists to help us explain how gases function and how they behave."}, {"title": "Graham\u2019s Law .txt", "text": "They help us develop a better understanding of gas functionality."}, {"title": "Graham\u2019s Law .txt", "text": "Now, one thing that we deduced from the kinetic theory was that kinetic energy, then your molecule, is directly proportional to temperature."}, {"title": "Graham\u2019s Law .txt", "text": "And that means if we have a gas system, a system of gas molecules, if we increase the overall temperature of our system, then on average, every molecule will have a higher kinetic energy."}, {"title": "Graham\u2019s Law .txt", "text": "And that's because kinetic energy is proportional to temperature."}, {"title": "Graham\u2019s Law .txt", "text": "So what happens in a system of gas molecules that is under constant temperature?"}, {"title": "Graham\u2019s Law .txt", "text": "Well, then, on average, the kinetic energy of any gas molecule, say gas molecule one, is the same as the kinetic energy, gas molecule number two."}, {"title": "Graham\u2019s Law .txt", "text": "So let's equate these guys and let's see where that leads us."}, {"title": "Graham\u2019s Law .txt", "text": "Let's suppose the kinetic energy of some gas molecule one is equal to kinetic energy of gas molecule two because they have the same temperature."}, {"title": "Graham\u2019s Law .txt", "text": "Now, let's also assume that gas molecule two has a larger mass than gas molecule one."}, {"title": "Graham\u2019s Law .txt", "text": "So gas molecule two is heavier."}, {"title": "Graham\u2019s Law .txt", "text": "So let's rewrite these guys in terms of our mathematical formula for kinetic energy, namely one two, MV squared."}, {"title": "Graham\u2019s Law .txt", "text": "The one subscript simply represents gas molecule one, and the two subscript simply represents gas molecule two."}, {"title": "Graham\u2019s Law .txt", "text": "So blue is one, red is two."}, {"title": "Graham\u2019s Law .txt", "text": "So one two m one, V one squared is equal to one two M two V two squared."}, {"title": "Graham\u2019s Law .txt", "text": "So let's cancel out the twos by multiplying each side by two."}, {"title": "Graham\u2019s Law .txt", "text": "And then let's bring our V two over and our m one over this way."}, {"title": "Graham\u2019s Law .txt", "text": "So we want velocities on the left side and masses on the right side."}, {"title": "Graham\u2019s Law .txt", "text": "We get the following formula v one squared divided by V two squared equals m two squared over m one squared."}, {"title": "Graham\u2019s Law .txt", "text": "And finally, let's take the square root of both sides."}, {"title": "Graham\u2019s Law .txt", "text": "What we get is these twos cancel."}, {"title": "Graham\u2019s Law .txt", "text": "Well, that's v one over V two."}, {"title": "Graham\u2019s Law .txt", "text": "And then we have the square root of m two divided by square root of m one."}, {"title": "Graham\u2019s Law .txt", "text": "Now, what does this tell us?"}, {"title": "Graham\u2019s Law .txt", "text": "Well, to gain a better understanding about what this tells us, we have to talk about a concept called effusion."}, {"title": "Graham\u2019s Law .txt", "text": "But before we talk about that, notice that velocity one will be greater if m one is smaller."}, {"title": "Graham\u2019s Law .txt", "text": "And likewise, velocity two will be greater if m two is smaller."}, {"title": "Graham\u2019s Law .txt", "text": "And we'll see that more clearly in the process of infusion."}, {"title": "Graham\u2019s Law .txt", "text": "So infusion is the movement of gas particles or molecules from high pressure to low pressure via a very, very tiny hole."}, {"title": "Graham\u2019s Law .txt", "text": "So to imagine this situation, let's look at this illustration."}, {"title": "Graham\u2019s Law .txt", "text": "Suppose we have a system, a Q."}, {"title": "Graham\u2019s Law .txt", "text": "And we have a very tiny hole in this queue."}, {"title": "Graham\u2019s Law .txt", "text": "And we have lots of molecules found inside our queue."}, {"title": "Graham\u2019s Law .txt", "text": "So we have two molecules."}, {"title": "Graham\u2019s Law .txt", "text": "The red molecules and the blue molecules."}, {"title": "Graham\u2019s Law .txt", "text": "Now, notice we have a high pressure on the inside and low pressure on the outside because our outside, we're assuming, is a vacuum."}, {"title": "Graham\u2019s Law .txt", "text": "Now, we make a very tiny incision, a very tiny hole."}, {"title": "Graham\u2019s Law .txt", "text": "And the diameter of this hole is much smaller than the distance between a two molecules."}, {"title": "Graham\u2019s Law .txt", "text": "That's our assumption."}, {"title": "Graham\u2019s Law .txt", "text": "So eventually, some of these molecules will hit the walls of the container."}, {"title": "Graham\u2019s Law .txt", "text": "At any given time, some of these molecules will hit the wall at exactly the spot where this hole is, and they will exit or escape the cube."}, {"title": "Graham\u2019s Law .txt", "text": "What this formula tells us is that the higher your velocity is, the more likely that you will collide with the wall at this position, at this point in time, and the more likely you will escape into the vacuum."}, {"title": "Graham\u2019s Law .txt", "text": "So we can rewrite these velocities as rates."}, {"title": "Graham\u2019s Law .txt", "text": "So the rate of effusion for gas one divided by the rate of infusion for gas two is equal to the square root of mass one divided by the square root of mass two."}, {"title": "Graham\u2019s Law .txt", "text": "And what this equation tells us, which is by the way, grams equation or Gram's law, is that the heavier the molecule is, the smaller its speed and therefore, the smaller its rate."}, {"title": "Graham\u2019s Law .txt", "text": "And our individual proportion is the following rate is directly proportional to one over square root of mass."}, {"title": "Graham\u2019s Law .txt", "text": "In other words, if our M is larger, then the denominator becomes larger, and so our fracture becomes smaller."}, {"title": "Graham\u2019s Law .txt", "text": "And so this guy is smaller."}, {"title": "Graham\u2019s Law .txt", "text": "Likewise, if if M is smaller, if it's less heavier, then this fraction becomes smaller, and one over a smaller number is a larger number."}, {"title": "Graham\u2019s Law .txt", "text": "And that means our rate is larger."}, {"title": "Graham\u2019s Law .txt", "text": "In other words, the higher the speed, the more likely you will collide with the walls, the more likely you will exit the cell."}, {"title": "Graham\u2019s Law .txt", "text": "And the only way that your speed will be higher in this equation is if your mass is smaller."}, {"title": "Graham\u2019s Law .txt", "text": "So lighter particles tend to it's used quicker than heavier particles."}, {"title": "Ideal Gas Law .txt", "text": "We have spoken about three gas laws that help us explain in their own individual way how gas molecules function on a macroscopic scale in the macroscopic gas system."}, {"title": "Ideal Gas Law .txt", "text": "Now, we've looked at Boyle's Law which answers questions such as why do balloons blow up or explode when you compress them by increasing pressure?"}, {"title": "Ideal Gas Law .txt", "text": "We've spoken about Charles Law which answers questions such as why do cartels deflate in the winter and inflate or expand in the summer?"}, {"title": "Ideal Gas Law .txt", "text": "And we've also looked at Avocadoso's Law which helps explain questions such as why do balloons become larger when you blow an air?"}, {"title": "Ideal Gas Law .txt", "text": "Now, all these three laws help explain macroscopic concepts of gases."}, {"title": "Ideal Gas Law .txt", "text": "Now, now we are ready to combine all three laws into a single super law that puts all three relationships into a single formula, into a single equation."}, {"title": "Ideal Gas Law .txt", "text": "And this equation is known as the ideal gas law."}, {"title": "Ideal Gas Law .txt", "text": "Now, recall that pressure is inversely proportional to volume which is exactly what this guy says."}, {"title": "Ideal Gas Law .txt", "text": "Pressure is inverse proportional to volume and directly proportional to N and T.\nThat's exactly what Charles Law in Evagondjo's Law tells us."}, {"title": "Ideal Gas Law .txt", "text": "Now, the only problem in this top portion is that we want to go from a proportionality sign to an equal sign."}, {"title": "Ideal Gas Law .txt", "text": "The way we adjust this guy, this top guy, so that we can equal them is by multiplying our right side or adjusting our right side by some constant R.\nThis is known as the ideal gas constant."}, {"title": "Ideal Gas Law .txt", "text": "So what problem remains?"}, {"title": "Ideal Gas Law .txt", "text": "What is R?"}, {"title": "Ideal Gas Law .txt", "text": "So, from experimental results, data shows that a temperature of zero Celsius and a pressure of one ATM and any 1 Mol of any gas will give us 22.4 liters of volume."}, {"title": "Ideal Gas Law .txt", "text": "And that means we have four unknowns."}, {"title": "Ideal Gas Law .txt", "text": "I mean, we have four knowns and one unknown."}, {"title": "Ideal Gas Law .txt", "text": "And that means if we plug the four knowns in, we'll get our unknown, namely our constant R.\nSo let's plug these guys in P times V divided by T times N. Simply rearrange these guys, plug our values in, and we get our gas constant R is equal to 0.826 atmospheres times literally by Kelvin times Mo."}, {"title": "Ideal Gas Law .txt", "text": "Now, this number might change if we play around with the units."}, {"title": "Ideal Gas Law .txt", "text": "But for these units, this will be our gas constant."}, {"title": "Ideal Gas Law .txt", "text": "So the question is how does an ideal gas law help us?"}, {"title": "Ideal Gas Law .txt", "text": "Well, it helps us in the following way."}, {"title": "Ideal Gas Law .txt", "text": "If we know three parameters, we can find and find them unknown."}, {"title": "Ideal Gas Law .txt", "text": "That's exactly what this formula tells us."}, {"title": "Ideal Gas Law .txt", "text": "If we know, for example, Nt and D, we can find P.\nOr if we know p, d and T will find N. Or if we know p, n and T will find D and so on."}, {"title": "Ideal Gas Law .txt", "text": "So let's do an example."}, {"title": "Ideal Gas Law .txt", "text": "Our example states that we want to calculate volume that 0.5 grams of methane occupied at 25 degrees Celsius and one atmospheric pressure."}, {"title": "Ideal Gas Law .txt", "text": "So we have one known, we have two knowns our our pressure."}, {"title": "Ideal Gas Law .txt", "text": "We have three knowns grams because remember, grams will translate into moles."}, {"title": "Ideal Gas Law .txt", "text": "We can find moles using grams."}, {"title": "Ideal Gas Law .txt", "text": "So our first step will be to find our third unknown."}, {"title": "Ideal Gas Law .txt", "text": "To find our number of moles."}, {"title": "Ideal Gas Law .txt", "text": "If we find that we have three knowns and one unknown, we'll suffer that unknown, namely this guy, and we'll get our answer."}, {"title": "Ideal Gas Law .txt", "text": "So to find the number of moles n, we simply take our number 0.5\ngrams of methane."}, {"title": "Ideal Gas Law .txt", "text": "Divide that by our molecular weight of methane grams cancel and we get moles on top."}, {"title": "Ideal Gas Law .txt", "text": "So 0.5\ngrams divided by 16 is 132, which is 0.3125 moles."}, {"title": "Ideal Gas Law .txt", "text": "We take this moles, plug it into our formula along with not 25 degrees Celsius, but 273 plus 25."}, {"title": "Ideal Gas Law .txt", "text": "Then one ATM and we'll get the following numbers plug that in and we get zero point 76 liters of methane will take up or occupy at this temperature, this pressure and this amount."}, {"title": "Electrolysis of Aqueous Sodium Chloride.txt", "text": "In this lecture, we're going to talk a bit more about the process of electrolysis."}, {"title": "Electrolysis of Aqueous Sodium Chloride.txt", "text": "Recall that voltanic cells are electrochemical cells that create electrical work from chemical energy."}, {"title": "Electrolysis of Aqueous Sodium Chloride.txt", "text": "On the contrary, electrolytic cells use up electrical work to power unfavorable redox reactions, such as as decomposition reactions."}, {"title": "Electrolysis of Aqueous Sodium Chloride.txt", "text": "Now, we already spoke about the decomposition of molten sodium chloride."}, {"title": "Electrolysis of Aqueous Sodium Chloride.txt", "text": "Now we're going to talk about the decomposition of aqueous sodium chloride."}, {"title": "Electrolysis of Aqueous Sodium Chloride.txt", "text": "And this guy is a little bit different because our solvent is water."}, {"title": "Electrolysis of Aqueous Sodium Chloride.txt", "text": "When we talk about molten sodium chloride, we didn't have any solvent."}, {"title": "Electrolysis of Aqueous Sodium Chloride.txt", "text": "So let's see how our solvent, namely water, affects our reaction."}, {"title": "Electrolysis of Aqueous Sodium Chloride.txt", "text": "So first, let's look at our electrolytic cell."}, {"title": "Electrolysis of Aqueous Sodium Chloride.txt", "text": "So in this cell, we have a battery, a voltage cell that powers our reaction, and it powers it by sending electrons this way."}, {"title": "Electrolysis of Aqueous Sodium Chloride.txt", "text": "So that means this electrode will collect these electrons, making it negatively charged."}, {"title": "Electrolysis of Aqueous Sodium Chloride.txt", "text": "At the same time, this electrode will lose electrons, making this guy positively charged, because electrons will want to flow from this guy to this guy."}, {"title": "Electrolysis of Aqueous Sodium Chloride.txt", "text": "So let's look at our solution."}, {"title": "Electrolysis of Aqueous Sodium Chloride.txt", "text": "Within our solution, we have a bunch of sodium ions dissolved and chloride ions dissolved."}, {"title": "Electrolysis of Aqueous Sodium Chloride.txt", "text": "The positively charged ions will be attracted to the negatively charged electrode."}, {"title": "Electrolysis of Aqueous Sodium Chloride.txt", "text": "So a lot of the sodium ions will move to the left side next to this negatively charged electrode."}, {"title": "Electrolysis of Aqueous Sodium Chloride.txt", "text": "Likewise, the negatively charged ions will move towards a positively charged electrode."}, {"title": "Electrolysis of Aqueous Sodium Chloride.txt", "text": "So all the corridions will collect next to the on the right side."}, {"title": "Electrolysis of Aqueous Sodium Chloride.txt", "text": "So anytime this positively charged sodium ion hits this negatively charged electrode, a transfer of electrons will occur."}, {"title": "Electrolysis of Aqueous Sodium Chloride.txt", "text": "So a sodium ion will gain electrons, and that means it's reduced."}, {"title": "Electrolysis of Aqueous Sodium Chloride.txt", "text": "And by definition, wherever reduction occurs, that's our cathode."}, {"title": "Electrolysis of Aqueous Sodium Chloride.txt", "text": "So this side of the cell is our cathode, and that means this side of the cell is the amo, because that's where oxidation takes place."}, {"title": "Electrolysis of Aqueous Sodium Chloride.txt", "text": "The chloride ions are oxidized and lose electrons, and these electrons jump into the electrode and travel on to this way, thus creating a circuit that moves in this direction."}, {"title": "Electrolysis of Aqueous Sodium Chloride.txt", "text": "Now, now that we know what our layout of our electrolytic cell is, let's talk about the oxidation and reduction reactions."}, {"title": "Electrolysis of Aqueous Sodium Chloride.txt", "text": "Now, when we spoke about molten sodium chloride, only one oxidation reaction was possible, and only one reduction reaction was possible."}, {"title": "Electrolysis of Aqueous Sodium Chloride.txt", "text": "But now we're in the presence of a solvent, namely water."}, {"title": "Electrolysis of Aqueous Sodium Chloride.txt", "text": "So water is also capable of undergoing oxidation, and water likewise, is also capable of undergoing reduction."}, {"title": "Electrolysis of Aqueous Sodium Chloride.txt", "text": "So let's look at oxidation first."}, {"title": "Electrolysis of Aqueous Sodium Chloride.txt", "text": "So what atoms are able to oxidize?"}, {"title": "Electrolysis of Aqueous Sodium Chloride.txt", "text": "Well, this atom could oxidize, and a water atom could oxidize."}, {"title": "Electrolysis of Aqueous Sodium Chloride.txt", "text": "Now, if this atom decides to oxidize, this is our oxidation reaction."}, {"title": "Electrolysis of Aqueous Sodium Chloride.txt", "text": "Now, if water decides to oxidize, namely the oxygen decides to oxidize, then this is our oxidation reactions."}, {"title": "Electrolysis of Aqueous Sodium Chloride.txt", "text": "How do we choose which one occurs?"}, {"title": "Electrolysis of Aqueous Sodium Chloride.txt", "text": "Well, the one that's more negative than one that's lower on the reduction HAP reaction table."}, {"title": "Electrolysis of Aqueous Sodium Chloride.txt", "text": "That's the one that is more likely to undergo oxidation."}, {"title": "Electrolysis of Aqueous Sodium Chloride.txt", "text": "And since this guy has a more negative cell voltage."}, {"title": "Electrolysis of Aqueous Sodium Chloride.txt", "text": "That means this guy is more likely to undergo oxidation."}, {"title": "Electrolysis of Aqueous Sodium Chloride.txt", "text": "And so this will be our oxidation reaction."}, {"title": "Electrolysis of Aqueous Sodium Chloride.txt", "text": "Likewise, let's look at reduction."}, {"title": "Electrolysis of Aqueous Sodium Chloride.txt", "text": "We have two possible reactions for a reduction."}, {"title": "Electrolysis of Aqueous Sodium Chloride.txt", "text": "Now, our sodium ion could be reduced into sodium solid, or our water molecule could be reduced into this guy."}, {"title": "Electrolysis of Aqueous Sodium Chloride.txt", "text": "Now let's look at which one is more likely to occur."}, {"title": "Electrolysis of Aqueous Sodium Chloride.txt", "text": "Now, for reduction, it's the opposite."}, {"title": "Electrolysis of Aqueous Sodium Chloride.txt", "text": "The more positive it is, the more likely it is to occur."}, {"title": "Electrolysis of Aqueous Sodium Chloride.txt", "text": "So whatever is higher up on the reduction half reaction table, that guy will be more likely to undergo reduction."}, {"title": "Electrolysis of Aqueous Sodium Chloride.txt", "text": "So since this is more positive, that means this will be our reduction reaction."}, {"title": "Electrolysis of Aqueous Sodium Chloride.txt", "text": "So now we must add up all these reactions except this one, because this one won't occur, this one will occur, this one will occur, and this one won't occur."}, {"title": "Electrolysis of Aqueous Sodium Chloride.txt", "text": "And that means we're still going to have these atoms down in our solution."}, {"title": "Electrolysis of Aqueous Sodium Chloride.txt", "text": "So we add this guy up, this guy up, and this guy up, and we get the following net reaction."}, {"title": "Electrolysis of Aqueous Sodium Chloride.txt", "text": "So when this guy and this guy react, they will create sodium or salt within solution."}, {"title": "Electrolysis of Aqueous Sodium Chloride.txt", "text": "Plus two molecules of water in a liquid state will produce diatomic gas, plus another diatomic gas, plus this two hydroxide acreage state and two sodium molecules in the acreage state."}, {"title": "Electrolysis of Aqueous Sodium Chloride.txt", "text": "We also add up these cell voltages and we get this following cell voltage."}, {"title": "Electrolysis of Aqueous Sodium Chloride.txt", "text": "So this is the amount of energy electrical work that needs to be put in by the battery to power this reaction."}, {"title": "Electrolysis of Aqueous Sodium Chloride.txt", "text": "So we see that decomposition reactions require work."}, {"title": "Electrolysis of Aqueous Sodium Chloride.txt", "text": "Well, why?"}, {"title": "Electrolysis of Aqueous Sodium Chloride.txt", "text": "Well, that's because they're unfavorable redox reactions."}, {"title": "Electrolysis of Aqueous Sodium Chloride.txt", "text": "So that's the difference between molten sodium chloride and aqueous sodium chloride."}, {"title": "Electrolysis of Aqueous Sodium Chloride.txt", "text": "In molten sodium chloride, the salvage wasn't present, water wasn't present."}, {"title": "Electrolysis of Aqueous Sodium Chloride.txt", "text": "And so there was only one oxidation and one reduction reaction in this and aqueous sodium chloride."}, {"title": "Electrolysis of Aqueous Sodium Chloride.txt", "text": "There are two possibilities for oxidation and reduction."}, {"title": "Electrolysis of Aqueous Sodium Chloride.txt", "text": "And you have to look at their cell voltages to choose."}, {"title": "Electrolysis of Aqueous Sodium Chloride.txt", "text": "For reduction, you choose the one that's more positive or less negative."}, {"title": "Electrolysis of Aqueous Sodium Chloride.txt", "text": "For oxidation, you choose the one that's less positive or more negative."}, {"title": "Electrolysis of Aqueous Sodium Chloride.txt", "text": "That's exactly what we did here."}, {"title": "Phase Diagram.txt", "text": "Pressure and temperature are two important insensible properties."}, {"title": "Phase Diagram.txt", "text": "Which simply means if I'm given a system and the system increases in size, well, our pressure and temperature will stay the same."}, {"title": "Phase Diagram.txt", "text": "Now phase diagrams use pressure and temperature to help us determine the phase of substance."}, {"title": "Phase Diagram.txt", "text": "So given some pressure and temperature, I could use the phase diagram to see what Theta substance is in."}, {"title": "Phase Diagram.txt", "text": "So here's our phase diagram."}, {"title": "Phase Diagram.txt", "text": "The y axis is pressure."}, {"title": "Phase Diagram.txt", "text": "The x axis is temperature."}, {"title": "Phase Diagram.txt", "text": "The phase diagram is broken down into three sections solid, liquid and gas."}, {"title": "Phase Diagram.txt", "text": "So to figure out what theta substance is in, we find the temperature and pressure."}, {"title": "Phase Diagram.txt", "text": "Suppose we're given some t and some p. So here's our T-R-P and here's our t. Now we first must find the point of intersection."}, {"title": "Phase Diagram.txt", "text": "So we draw a line up or draw a line across?"}, {"title": "Phase Diagram.txt", "text": "Here's our point intersection."}, {"title": "Phase Diagram.txt", "text": "And this point lies in a solid phase."}, {"title": "Phase Diagram.txt", "text": "And that means it must be a solid at this particular temperature and this particular pressure."}, {"title": "Phase Diagram.txt", "text": "Now, if we keep the pressure the same and, say, increase our temperature to say, this point, well, then we have to draw the line all the way here."}, {"title": "Phase Diagram.txt", "text": "And then the section will be here at this pressure."}, {"title": "Phase Diagram.txt", "text": "At this temperature, it will be in a gas phase."}, {"title": "Phase Diagram.txt", "text": "Now, the lines or boundaries represent or signify dynamic equilibrium between two or more phases."}, {"title": "Phase Diagram.txt", "text": "For example, suppose I'm on this boundary and on this line well, at this line, the rate at which the soil becomes a liquid is the same as the rate at which the liquid becomes a solid."}, {"title": "Phase Diagram.txt", "text": "Okay?"}, {"title": "Phase Diagram.txt", "text": "Now only one point exists called a triple point."}, {"title": "Phase Diagram.txt", "text": "The black tie."}, {"title": "Phase Diagram.txt", "text": "The middle."}, {"title": "Phase Diagram.txt", "text": "And at this point, all three phases are in dynamic equilibrium with each other."}, {"title": "Phase Diagram.txt", "text": "Now, another important point exists called a critical point."}, {"title": "Phase Diagram.txt", "text": "And a critical point corresponds to a certain pressure and temperature above which our substance has both properties of liquid and gas."}, {"title": "Phase Diagram.txt", "text": "Okay?"}, {"title": "Phase Diagram.txt", "text": "So this fluid is now called supercritical fluid."}, {"title": "Phase Diagram.txt", "text": "And this is our critical point."}, {"title": "Phase Diagram.txt", "text": "So our critical temperature is we draw a line."}, {"title": "Phase Diagram.txt", "text": "Down is right here."}, {"title": "Phase Diagram.txt", "text": "And now critical pressure is we draw a line across right here above this pressure and above this temperature."}, {"title": "Phase Diagram.txt", "text": "Our substance is a supercritical fluid."}, {"title": "Phase Diagram.txt", "text": "And that means it shares properties with gasses and liquids."}, {"title": "Regioselective and Regiospecific.txt", "text": "So let's imagine for a moment that we're taking a walk on a straight path and eventually we come to a fourth in a row."}, {"title": "Regioselective and Regiospecific.txt", "text": "Now, at the fourth, we have several options."}, {"title": "Regioselective and Regiospecific.txt", "text": "We can either take one pathway that will lead us to one place, or we can take a different pathway that will lead us to a different place."}, {"title": "Regioselective and Regiospecific.txt", "text": "Now, in the same way, when certain compounds react, different pathways are possible, and each pathway will lead us to a different compound."}, {"title": "Regioselective and Regiospecific.txt", "text": "So let's examine the following example."}, {"title": "Regioselective and Regiospecific.txt", "text": "Let's say we have the following two compounds."}, {"title": "Regioselective and Regiospecific.txt", "text": "We have hydrochloric acid reacts with an alkene."}, {"title": "Regioselective and Regiospecific.txt", "text": "Now, two different pathways are possible."}, {"title": "Regioselective and Regiospecific.txt", "text": "In other words, this lewis base can take this H atom and follow pathway one, in which the H atom goes on this side of the carbon."}, {"title": "Regioselective and Regiospecific.txt", "text": "So on this carbon, it attaches to the second carbon of the double bond."}, {"title": "Regioselective and Regiospecific.txt", "text": "Or it can take pathway two, in which the lewis acid takes this H and attaches that H to the other side of the double bond to this carbon."}, {"title": "Regioselective and Regiospecific.txt", "text": "So we can either take pathway one and form a tertiary carbocation, or we can take pathway two and form a primary carbocation."}, {"title": "Regioselective and Regiospecific.txt", "text": "In each reaction, a different product is formed."}, {"title": "Regioselective and Regiospecific.txt", "text": "So when our reaction takes pathway one, we form one product."}, {"title": "Regioselective and Regiospecific.txt", "text": "When our reaction takes place and follows pathway two, we form a different product."}, {"title": "Regioselective and Regiospecific.txt", "text": "So if a reaction takes place on an unsymmetrical compound such as this alkane, unsymmetrical simply means if we cut this in half, the left is different from the right."}, {"title": "Regioselective and Regiospecific.txt", "text": "So if a reaction takes place on an oxymetrical compound, different pathways are possible."}, {"title": "Regioselective and Regiospecific.txt", "text": "And this is known as regiochemistry."}, {"title": "Regioselective and Regiospecific.txt", "text": "Regeochemistry is basically the study of the different pathways that our two reactants can take."}, {"title": "Regioselective and Regiospecific.txt", "text": "Now, in the reaction above, pathway one is more favorable, it's more likely to occur."}, {"title": "Regioselective and Regiospecific.txt", "text": "And that's because this intermediate carbocation, this tertiary carbocation is more stable than this primary carbocation."}, {"title": "Regioselective and Regiospecific.txt", "text": "And we'll examine that in a future lecture."}, {"title": "Regioselective and Regiospecific.txt", "text": "So because pathway one is more favorable, it's more stable, it's more likely to take place."}, {"title": "Regioselective and Regiospecific.txt", "text": "And generally, when a reaction can occur in several ways and one of the pathways predominates the reaction is called regioselective."}, {"title": "Regioselective and Regiospecific.txt", "text": "So this reaction is regioselective because pathway one predominates over pathway two."}, {"title": "Regioselective and Regiospecific.txt", "text": "Pathway one is more likely to take place because this intermediate is more stable than this intermediate."}, {"title": "Regioselective and Regiospecific.txt", "text": "Now, in such a reaction, one of the final products predominates, and this is known as reggiospecific reaction."}, {"title": "Regioselective and Regiospecific.txt", "text": "So this reaction is regio selective because pathway one predominates, it's more likely to take place."}, {"title": "Regioselective and Regiospecific.txt", "text": "And because pathway one predominates, the product of pathway one will also predominate."}, {"title": "Regioselective and Regiospecific.txt", "text": "And so this reaction is also known as regiospecific different."}, {"title": "Clausius Clapeyron Equation .txt", "text": "In this lecture, we're going to talk about a concept called a closed cliperon relation."}, {"title": "Clausius Clapeyron Equation .txt", "text": "Now, vapor pressure is very important when we talk about this relation."}, {"title": "Clausius Clapeyron Equation .txt", "text": "So if you're not sure about vapor pressure, check out the video below."}, {"title": "Clausius Clapeyron Equation .txt", "text": "Now, the vapor pressure of a liquid increases with temperature."}, {"title": "Clausius Clapeyron Equation .txt", "text": "That means if you heat up a liquid, more molecules will evaporate, thereby increasing the vapor pressure of our liquid."}, {"title": "Clausius Clapeyron Equation .txt", "text": "Now, you could also graph vapor pressure versus temperature on an x y plane."}, {"title": "Clausius Clapeyron Equation .txt", "text": "And what we get is an exponential curve."}, {"title": "Clausius Clapeyron Equation .txt", "text": "Now, the y axis is pressure, the X axis is temperature."}, {"title": "Clausius Clapeyron Equation .txt", "text": "What this curve tells us is that identical changes on the X axis produces different changes on the y axis."}, {"title": "Clausius Clapeyron Equation .txt", "text": "So, for example, if we take an identical change at higher pressures, we see that that produces a greater pressure difference than at lower temperatures."}, {"title": "Clausius Clapeyron Equation .txt", "text": "And that is clearly seen because this guy is much bigger than this guy."}, {"title": "Clausius Clapeyron Equation .txt", "text": "Now, what this relation doesn't tell us is the slope of the line."}, {"title": "Clausius Clapeyron Equation .txt", "text": "It would be very nice if we could somehow find the slope of the line."}, {"title": "Clausius Clapeyron Equation .txt", "text": "Unfortunately, the only way to find the slope of the line in this situation is to use calculus and find the slope of the line tangent to the curve at each point."}, {"title": "Clausius Clapeyron Equation .txt", "text": "But that's very tedious and takes a lot of work."}, {"title": "Clausius Clapeyron Equation .txt", "text": "So it would be very nice if we could somehow represent vapor pressure and temperature in an easier relation, in an easier function."}, {"title": "Clausius Clapeyron Equation .txt", "text": "And mathematically, one of the most simplest functions is a linear function."}, {"title": "Clausius Clapeyron Equation .txt", "text": "And a linear function is represented by this equation y equals MX plus B, where y is our range value, x is our domain value, m is a constant slope, and B is the y intercept."}, {"title": "Clausius Clapeyron Equation .txt", "text": "Now, this is exactly what the closest Clayton relation does."}, {"title": "Clausius Clapeyron Equation .txt", "text": "These were two scientists who developed mathematically and the experimental result, this relationship where this is our y value, this is our slope, this is our X value, and this is our Y intercept."}, {"title": "Clausius Clapeyron Equation .txt", "text": "This is the natural log of vapor pressure of our liquid."}, {"title": "Clausius Clapeyron Equation .txt", "text": "This, our slope, is the negative of the change in enthalpy about vaporization of the liquid over our gas constant R. Our X value is one over t or one over temperature of the liquid."}, {"title": "Clausius Clapeyron Equation .txt", "text": "And this is a constant that depends on the liquid being used."}, {"title": "Clausius Clapeyron Equation .txt", "text": "And if you graph this, you get exactly a linear line that has a negative slope shown by this negative sign here."}, {"title": "Clausius Clapeyron Equation .txt", "text": "So the magnitude of this value is this value here."}, {"title": "Clausius Clapeyron Equation .txt", "text": "And in fact, this is very useful because now if we're given some vapor pressure and we're given the temperature and we know the constant, we can easily find our slope."}, {"title": "Clausius Clapeyron Equation .txt", "text": "That is, we can find the change in enthalpy of vaporization."}, {"title": "Clausius Clapeyron Equation .txt", "text": "Likewise, if we know this guy and this guy, we could find this guy."}, {"title": "Clausius Clapeyron Equation .txt", "text": "And if we know this guy and this guy, we can find the vapor pressure."}, {"title": "Clausius Clapeyron Equation .txt", "text": "So it's very useful."}, {"title": "Clausius Clapeyron Equation .txt", "text": "And if you want to practice using different problems, check out the link below."}, {"title": "Clausius Clapeyron Equation .txt", "text": "Now, let's talk about these graphs for a quick second."}, {"title": "Clausius Clapeyron Equation .txt", "text": "Let's compare this graph and this graph."}, {"title": "Clausius Clapeyron Equation .txt", "text": "Well, this graph we see that this way increases in temperature."}, {"title": "Clausius Clapeyron Equation .txt", "text": "But on this side, this way is the increase in temperature because one over a larger number is a smaller number than one over a smaller number."}, {"title": "Clausius Clapeyron Equation .txt", "text": "So the larger the temperature, the closer the value will be an x axis to zero."}, {"title": "Clausius Clapeyron Equation .txt", "text": "And in fact, what happens when this T becomes very large, when it tends to zero, when it tends to a very large number, when it tends to infinity, well, this becomes zero."}, {"title": "Clausius Clapeyron Equation .txt", "text": "And we see that at zero we get our Y intercept that is C.\nAnd this equation shows the same exact thing."}, {"title": "Clausius Clapeyron Equation .txt", "text": "When T becomes a very large number, this whole number tends to zero."}, {"title": "Clausius Clapeyron Equation .txt", "text": "And so we simply get our log of our vapor pressure is equal to a constant C and we see exactly that on this graph."}, {"title": "Clausius Clapeyron Equation .txt", "text": "Another thing to realize is that the slope or the magnitude of the slope represents our change in enthalpy of vaporization."}, {"title": "Clausius Clapeyron Equation .txt", "text": "So for one liquid, this might be the slope for another liquid, say, if this was the slope for water, then alcohol would have a slope of this because alcohol has a smaller change in entry enthalpy of vaporization."}, {"title": "Clausius Clapeyron Equation .txt", "text": "So this would be the slope of alcohol liquid and this will be the slope of, say, water."}, {"title": "Equilibrium constant of Redox reaction example .txt", "text": "In this example, we begin with the following redox reaction on the standard conditions at a 25 degree Celsius."}, {"title": "Equilibrium constant of Redox reaction example .txt", "text": "Now, our goal is to find the equilibrium constant of the above redox reaction on the DTA conditions."}, {"title": "Equilibrium constant of Redox reaction example .txt", "text": "So let's begin by first writing out the two half reactions of this reduction reaction."}, {"title": "Equilibrium constant of Redox reaction example .txt", "text": "So let's see which guy is oxidized and which guy is reduced."}, {"title": "Equilibrium constant of Redox reaction example .txt", "text": "Well, our iron atom goes from a neutral charge to a plus two charge, while our cavmium atom goes from a plus two charge to a neutral charge."}, {"title": "Equilibrium constant of Redox reaction example .txt", "text": "That means this atom loses two electrons and this atom gains those same two electrons."}, {"title": "Equilibrium constant of Redox reaction example .txt", "text": "So this is our oxidized atom and our reduced atom or our reducing agent and oxidizing agent."}, {"title": "Equilibrium constant of Redox reaction example .txt", "text": "So let's go to step one and let's see our two half reactions."}, {"title": "Equilibrium constant of Redox reaction example .txt", "text": "So our oxidation half reaction is the following."}, {"title": "Equilibrium constant of Redox reaction example .txt", "text": "Our solid iron becomes a positively charged molecule plus two electrons because it releases those two electrons while our cadmium aqueous atom gains those two electrons forming our cadmium solid."}, {"title": "Equilibrium constant of Redox reaction example .txt", "text": "So this is our reduction reaction and oxidation reaction."}, {"title": "Equilibrium constant of Redox reaction example .txt", "text": "So let's look at the cell diagram for this electrochemical cell."}, {"title": "Equilibrium constant of Redox reaction example .txt", "text": "So remember, these two vertical lines represent the sole bridge and these guys simply represent separations of phases."}, {"title": "Equilibrium constant of Redox reaction example .txt", "text": "So this and this are in different phases and these guys are in different phases also."}, {"title": "Equilibrium constant of Redox reaction example .txt", "text": "So this is our anode and this is our cathode."}, {"title": "Equilibrium constant of Redox reaction example .txt", "text": "So what happens is two electrons leave this atom forming our aqueous iron atom and these two electrons travel via the conductor to this guy reacting with this positively charged atom forming our solid cadmium."}, {"title": "Equilibrium constant of Redox reaction example .txt", "text": "So let's go to step two."}, {"title": "Equilibrium constant of Redox reaction example .txt", "text": "Now, in step two and three, what we want to do or do is find a cell voltage of our electrochemical cell and then use the cell voltage to find our equilibrium constant KC."}, {"title": "Equilibrium constant of Redox reaction example .txt", "text": "So let's go to step two."}, {"title": "Equilibrium constant of Redox reaction example .txt", "text": "Now, this is our formula that we want to use to find the cell voltage where this is the cell voltage of the reduction reaction and the cell voltage of the oxidation reaction."}, {"title": "Equilibrium constant of Redox reaction example .txt", "text": "Now, we basically look these guys up on our table for reduction half reactions on the statement conditions and we find that our reduction cell voltage is zero point 43 negative, while our oxidation half reaction is negative zero point 44."}, {"title": "Equilibrium constant of Redox reaction example .txt", "text": "Well, actually our reduction going this way because only reduction half reactions are listed."}, {"title": "Equilibrium constant of Redox reaction example .txt", "text": "So we have to look at the guy going this way."}, {"title": "Equilibrium constant of Redox reaction example .txt", "text": "So that is negative zero point 44."}, {"title": "Equilibrium constant of Redox reaction example .txt", "text": "Now, I put this negative here in here because we want to convert this to an oxidation because in this anode oxidation that reduction occurs and that's why we have the negative sign here."}, {"title": "Equilibrium constant of Redox reaction example .txt", "text": "So what we get is these negatives become a positive and we basically add this guy to this guy and we get zero point 37 volts."}, {"title": "Equilibrium constant of Redox reaction example .txt", "text": "This is our cell voltage of our electrochemical cell."}, {"title": "Equilibrium constant of Redox reaction example .txt", "text": "Now, in the previous lecture we learned that there's a relationship between our cell voltage and our equilibrium constant, namely this equation here."}, {"title": "Equilibrium constant of Redox reaction example .txt", "text": "Now, we also saw in that same lecture that we can convert this formula at 25 degrees Celsius to the following formula."}, {"title": "Equilibrium constant of Redox reaction example .txt", "text": "Log k equals number of moles times our cell voltage divided by this number here."}, {"title": "Equilibrium constant of Redox reaction example .txt", "text": "Zero point 52."}, {"title": "Equilibrium constant of Redox reaction example .txt", "text": "Now, this number comes from the fact that both r and F are constants."}, {"title": "Equilibrium constant of Redox reaction example .txt", "text": "And at 25 degrees Celsius, t is also constant."}, {"title": "Equilibrium constant of Redox reaction example .txt", "text": "Now t is in Kelvin."}, {"title": "Equilibrium constant of Redox reaction example .txt", "text": "And we also basically converted our natural log to log of base ten."}, {"title": "Equilibrium constant of Redox reaction example .txt", "text": "Now, let's plug our guides in."}, {"title": "Equilibrium constant of Redox reaction example .txt", "text": "So our E is from here, and n, we look at this equation."}, {"title": "Equilibrium constant of Redox reaction example .txt", "text": "We see that N represents two moles of electrons."}, {"title": "Equilibrium constant of Redox reaction example .txt", "text": "So n is two."}, {"title": "Equilibrium constant of Redox reaction example .txt", "text": "That's what we get."}, {"title": "Equilibrium constant of Redox reaction example .txt", "text": "Two times zero point 37 results from this guy divided by zero point 52, and we get 1.25 equals log k.\nNow, we change this entire thing to exponents, and we get ten to the 1.5."}, {"title": "Equilibrium constant of Redox reaction example .txt", "text": "You plug that into the calculator, and it's approximately 17.8."}, {"title": "Equilibrium constant of Redox reaction example .txt", "text": "So our K is 17.8."}, {"title": "Equilibrium constant of Redox reaction example .txt", "text": "And what does that mean?"}, {"title": "Equilibrium constant of Redox reaction example .txt", "text": "Well, remember we said if our K is above one, that means our reaction is product favorite."}, {"title": "Equilibrium constant of Redox reaction example .txt", "text": "It's spontaneous."}, {"title": "Equilibrium constant of Redox reaction example .txt", "text": "So this guy, the equilibrium lies on the right."}, {"title": "Equilibrium constant of Redox reaction example .txt", "text": "That means almost all of these guys are converted to our products."}, {"title": "Equilibrium constant of Redox reaction example .txt", "text": "And this is the same thing as our e. Remember, our E says what our E gives us a positive value for cell voltage and what the a positive value for cell voltage mean?"}, {"title": "Equilibrium constant of Redox reaction example .txt", "text": "Remember, a positive value for cell voltage means our reaction is product favored, and a negative value means it's reacting favored."}, {"title": "Equilibrium constant of Redox reaction example .txt", "text": "So this and this guy agree, and they state that this reaction will be favored in this direction."}, {"title": "Raoul\u2019s Law Example .txt", "text": "In this example, we begin with 100 MLS of water found in this container."}, {"title": "Raoul\u2019s Law Example .txt", "text": "100 MLS of ethylene glycol found in this container."}, {"title": "Raoul\u2019s Law Example .txt", "text": "And we're told that the vapor pressure of pure water is 500 millimeter D.\nAnd what that basically says is the pressure exerted by these molecules, the gas molecules is is 500."}, {"title": "Raoul\u2019s Law Example .txt", "text": "What we want to do is we want to mix these two containers and then find the bigger pressure of water."}, {"title": "Raoul\u2019s Law Example .txt", "text": "So we want to mix them and find the pressure exerted by these water molecules on the walls of the container."}, {"title": "Raoul\u2019s Law Example .txt", "text": "The first step is to find the moles of water."}, {"title": "Raoul\u2019s Law Example .txt", "text": "The second step is to find the moles of ethylene glycol."}, {"title": "Raoul\u2019s Law Example .txt", "text": "And the third step is to use the formula to find vapor pressure."}, {"title": "Raoul\u2019s Law Example .txt", "text": "Now, in the first step, before we find the moles, we first have to find the amount in grams of water."}, {"title": "Raoul\u2019s Law Example .txt", "text": "To find the amount of grams of water, we must first look up the density of water."}, {"title": "Raoul\u2019s Law Example .txt", "text": "The density of water is 1 gram per ML."}, {"title": "Raoul\u2019s Law Example .txt", "text": "So we take our volume of 100 MLS multiplied by 1 gram per ML the MLS can't sell and we get 100 grams of water in our beaker."}, {"title": "Raoul\u2019s Law Example .txt", "text": "Now, in the second step, we have to find the molecular weight of water."}, {"title": "Raoul\u2019s Law Example .txt", "text": "To find a molecular weight of water, we simply add up the atomic weights."}, {"title": "Raoul\u2019s Law Example .txt", "text": "So oxygen is 16 grams/mol plus two times because we have a substitute to 1 gram per mole, gives us 18 grams/mol."}, {"title": "Raoul\u2019s Law Example .txt", "text": "So the molecular weight of water is 18 grams/mol."}, {"title": "Raoul\u2019s Law Example .txt", "text": "Finally, we take this guy divided by this guy and we get 5.56\nmoles of water."}, {"title": "Raoul\u2019s Law Example .txt", "text": "That's how you find moles."}, {"title": "Raoul\u2019s Law Example .txt", "text": "The second step is the same exact step, except it's for ethylene glycol."}, {"title": "Raoul\u2019s Law Example .txt", "text": "Now we have to look up the density of ethylene glycol and the molecular formula for ethylene glycol."}, {"title": "Raoul\u2019s Law Example .txt", "text": "So we follow the same exact steps, 100 ML, because we have 100 times 1.15 gives us the amount of cancer, 115 grams of ethylene glycol."}, {"title": "Raoul\u2019s Law Example .txt", "text": "So a little bit more than water."}, {"title": "Raoul\u2019s Law Example .txt", "text": "Our second step is to find the molecular weight of ethylene glycol."}, {"title": "Raoul\u2019s Law Example .txt", "text": "We follow the same exact step, we add up the atomic weights and we get 62 grams/mol."}, {"title": "Raoul\u2019s Law Example .txt", "text": "Finally, to find the moles, we take our amount in grams divided by our molecular formula and we get 115 divided by 62 equals 1.85 moles of ethylene glycol."}, {"title": "Raoul\u2019s Law Example .txt", "text": "Finally, we use our formula to find out vapor pressure of the water molecules in this system."}, {"title": "Raoul\u2019s Law Example .txt", "text": "We simply multiply the mole fraction of water times the vapor pressure of water in the initial system and that is 5.51 divided by the total number of moles."}, {"title": "Raoul\u2019s Law Example .txt", "text": "The mole fraction 5.56\nplus 1.85 gives us some fraction."}, {"title": "Raoul\u2019s Law Example .txt", "text": "That fraction is multiplied by 500 and that gives us 375.17\nmmhg and that's the bigger pressure of these water molecules."}, {"title": "Raoul\u2019s Law Example .txt", "text": "Now it should be less."}, {"title": "Raoul\u2019s Law Example .txt", "text": "And that's because we have less water molecules on the surface, because now we have ethylene glycol molecules on the surface."}, {"title": "Raoul\u2019s Law Example .txt", "text": "And so less water molecules are evaporating."}, {"title": "Raoul\u2019s Law Example .txt", "text": "And that means that bigger pressure water in the new system should be less."}, {"title": "Raoul\u2019s Law Example .txt", "text": "And it is less."}, {"title": "Acidity of Alkynes .txt", "text": "So let's briefly discuss the acidity of alkynes."}, {"title": "Acidity of Alkynes .txt", "text": "And let's compare to the acidity of alkanes."}, {"title": "Acidity of Alkynes .txt", "text": "So, as an example, let's use the simplest alkyne acetylene, and let's use the simplest alkane known as methane."}, {"title": "Acidity of Alkynes .txt", "text": "So we basically want to determine which one of these two hydrocarbon compounds is a better Bronx Laric acid."}, {"title": "Acidity of Alkynes .txt", "text": "Recall that a bronciid Laric acid is a compound that is capable of donating NH plus ion."}, {"title": "Acidity of Alkynes .txt", "text": "So we want to figure out which one of these compounds is better at donating NH plus atom."}, {"title": "Acidity of Alkynes .txt", "text": "So let's look at reaction one."}, {"title": "Acidity of Alkynes .txt", "text": "In reaction one, we have a methane molecule or a methane compound dissociating or donating NH plus atom and also creating a methion anion."}, {"title": "Acidity of Alkynes .txt", "text": "So this method has a net charge of negative one because it has a lone pair of electrons, non bonding electrons found on the carbon."}, {"title": "Acidity of Alkynes .txt", "text": "So let's look at reaction two in reaction to our acetylene, dissociates into an H plus atom, and it also creates an anion called acetylene."}, {"title": "Acidity of Alkynes .txt", "text": "Now, this acetylene also has a net charge of negative one because it also has a lone pair of non bonding electrons on this first carbon."}, {"title": "Acidity of Alkynes .txt", "text": "So which one of these reactions is more likely to occur?"}, {"title": "Acidity of Alkynes .txt", "text": "In other words, which one of these acids is a better acid?"}, {"title": "Acidity of Alkynes .txt", "text": "Well, it turns out from experimental results, we know that acetylene is a better acid."}, {"title": "Acidity of Alkynes .txt", "text": "In fact, acetylene is ten to 30 times better at donating an H plus atom than this methane compound."}, {"title": "Acidity of Alkynes .txt", "text": "So why is that?"}, {"title": "Acidity of Alkynes .txt", "text": "Why is it that this hydrocarbon is so much better at donating an H plus atom than this simpler hydrocarbon?"}, {"title": "Acidity of Alkynes .txt", "text": "Well, it turns out the reason is this anion is much more stable than this anion, and therefore, this reaction is much more likely to take place."}, {"title": "Acidity of Alkynes .txt", "text": "So now let's examine why this compound, this anion, is much more stable."}, {"title": "Acidity of Alkynes .txt", "text": "And let's look at the orbitals of these two compounds."}, {"title": "Acidity of Alkynes .txt", "text": "So let's begin with our methi."}, {"title": "Acidity of Alkynes .txt", "text": "So the lone pair of electrons in the methyde molecule in the methi compound are found in the SP three hybridized orbital."}, {"title": "Acidity of Alkynes .txt", "text": "Remember, SP three contains 25% S character and 75% P character."}, {"title": "Acidity of Alkynes .txt", "text": "Now let's look at our second anion."}, {"title": "Acidity of Alkynes .txt", "text": "So in this anion, our lone pair of electrons are found in an SP orbital."}, {"title": "Acidity of Alkynes .txt", "text": "In an SP hybridized orbital, an SP orbital is an orbital that has 50% S character and 50% P character."}, {"title": "Acidity of Alkynes .txt", "text": "So this has much more S character than this compound."}, {"title": "Acidity of Alkynes .txt", "text": "And recall that the more S character a bond or an orbital has, the more stabilizing or the more stable the electrons in that bond will be."}, {"title": "Acidity of Alkynes .txt", "text": "And because this has much more S character than this, the electrons here are more stable."}, {"title": "Acidity of Alkynes .txt", "text": "And therefore, this compound is more stable than this anion."}, {"title": "Acidity of Alkynes .txt", "text": "And that means this reaction will be more likely to take place."}, {"title": "Acidity of Alkynes .txt", "text": "Recall that electrons found closer to our proton, to our nucleus are more stable."}, {"title": "Acidity of Alkynes .txt", "text": "They're lower in energy."}, {"title": "Acidity of Alkynes .txt", "text": "And that's exactly why when electrons are found in the s orbital, they're more stable than if they're found in the p orbital, because the S orbital is closer to the nucleus than the p orbital."}, {"title": "Acidity of Alkynes .txt", "text": "And therefore, if we have more S character, which we have in this SP hyperbased orbital, those electrons will be more stable because they are closer to the nucleus."}, {"title": "Acidity of Alkynes .txt", "text": "So once again, electrons found closer to the nucleus are more stable."}, {"title": "Acidity of Alkynes .txt", "text": "Therefore, since that seed ali contains more S character 60% in the SP orbital than the methi, which contains 25% S character, acetyllide is more stable."}, {"title": "Acidity of Alkynes .txt", "text": "So this anion is more stable than this anion once again, because those electrons are found in a 50% S character versus a 25% S character orbital."}, {"title": "Acidity of Alkynes .txt", "text": "So therefore, acetylalene, this guy is more likely to release an H atom or an H ion than our methane."}, {"title": "Acidity of Alkynes .txt", "text": "Now, notice one important detail in this lecture."}, {"title": "Acidity of Alkynes .txt", "text": "We've compared the acetylene to methane."}, {"title": "Acidity of Alkynes .txt", "text": "So we said that this is a relatively good acid."}, {"title": "Acidity of Alkynes .txt", "text": "Relatively."}, {"title": "Acidity of Alkynes .txt", "text": "Meaning that this compared to this, if we compare our acetylene to a very good acid such as hydrochloric acid or hydrobromic acid, we see that this becomes a very weak acid when compared to strong acids like that."}, {"title": "Acidity of Alkynes .txt", "text": "But if comparing hydrocarbons, alkines are better acid donors or H plus ion donors than our alkanes, and likewise for the same reason, alkynes are also better at donating an H ion than alkanes are."}, {"title": "Combination, Decomposition, Displacement and Combustion Reactions .txt", "text": "Now, in this list, you're working a look at some very common chemical reactions."}, {"title": "Combination, Decomposition, Displacement and Combustion Reactions .txt", "text": "So let's begin."}, {"title": "Combination, Decomposition, Displacement and Combustion Reactions .txt", "text": "Let's look at a combination reaction."}, {"title": "Combination, Decomposition, Displacement and Combustion Reactions .txt", "text": "Now, a combination reaction is exactly what the name applies."}, {"title": "Combination, Decomposition, Displacement and Combustion Reactions .txt", "text": "Two or more reactants combined by forming bonds to form a new compound with a new molecular formula."}, {"title": "Combination, Decomposition, Displacement and Combustion Reactions .txt", "text": "Now let's look at our hypothetical example."}, {"title": "Combination, Decomposition, Displacement and Combustion Reactions .txt", "text": "In our example, we have two reactants, A and B react combined to produce a new product, a new compound, namely AB."}, {"title": "Combination, Decomposition, Displacement and Combustion Reactions .txt", "text": "Now let's look at a very common example."}, {"title": "Combination, Decomposition, Displacement and Combustion Reactions .txt", "text": "Whenever 1 mol of solid burns with 1 mol of diatomic oxygen in the gas state, it produces 1 mol of carbon dioxide in the gas state."}, {"title": "Combination, Decomposition, Displacement and Combustion Reactions .txt", "text": "Now, this is a very common combination reaction."}, {"title": "Combination, Decomposition, Displacement and Combustion Reactions .txt", "text": "And note that this triangle on top of the arrow means that heat must be added for our reaction to occur."}, {"title": "Combination, Decomposition, Displacement and Combustion Reactions .txt", "text": "That's what this triangle means."}, {"title": "Combination, Decomposition, Displacement and Combustion Reactions .txt", "text": "It doesn't mean change."}, {"title": "Combination, Decomposition, Displacement and Combustion Reactions .txt", "text": "It means energy heat."}, {"title": "Combination, Decomposition, Displacement and Combustion Reactions .txt", "text": "Now let's look at a very common second type of chemical reaction known as decomposition reactions."}, {"title": "Combination, Decomposition, Displacement and Combustion Reactions .txt", "text": "Now, decomposition reactions are essentially the reverse of combination reactions, where in combination reactions, two reactants combine in decomposition reactions, a reactant, decomposes or dissociates into two or more new compounds."}, {"title": "Combination, Decomposition, Displacement and Combustion Reactions .txt", "text": "So in our hypothetical example, we have reactant AB, breaks down or decomposes into two new products, A plus B."}, {"title": "Combination, Decomposition, Displacement and Combustion Reactions .txt", "text": "Now let's look at a very common example."}, {"title": "Combination, Decomposition, Displacement and Combustion Reactions .txt", "text": "Now, the hydrolysis of water or the decomposition of water."}, {"title": "Combination, Decomposition, Displacement and Combustion Reactions .txt", "text": "In other words, two water molecules or two moles of H two in a liquid state react to produce 1 mol of O, two in a gas state, and two moles of diatomic H, two in the gas state."}, {"title": "Combination, Decomposition, Displacement and Combustion Reactions .txt", "text": "Now let's look at a third type and a fourth type of chemical reactions, namely single and double displacement."}, {"title": "Combination, Decomposition, Displacement and Combustion Reactions .txt", "text": "Now, single displacement reactions are also known as substitution reactions."}, {"title": "Combination, Decomposition, Displacement and Combustion Reactions .txt", "text": "And double displacement reactions are also known as metaphosis reactions."}, {"title": "Combination, Decomposition, Displacement and Combustion Reactions .txt", "text": "So let's look at a single or substitution chemical reaction."}, {"title": "Combination, Decomposition, Displacement and Combustion Reactions .txt", "text": "So A plus B or AB plus C. What happens is that the bond between A and B is broken."}, {"title": "Combination, Decomposition, Displacement and Combustion Reactions .txt", "text": "So B dissociates from A forming its own reactant, while A C combines with A displacing this B."}, {"title": "Combination, Decomposition, Displacement and Combustion Reactions .txt", "text": "So basically, C kicks out our B and forms a bond with A forming AC plus B."}, {"title": "Combination, Decomposition, Displacement and Combustion Reactions .txt", "text": "And this is a single displacement reaction or substitution reaction."}, {"title": "Combination, Decomposition, Displacement and Combustion Reactions .txt", "text": "Now, a very common example is when two moles of hydrochloric acid in an Aqueous state react with 1 mol of magnesium solid."}, {"title": "Combination, Decomposition, Displacement and Combustion Reactions .txt", "text": "This produces 1 mol of Mg CL, two in the Aqueous state, and 1 mol of diatomic H two in a gas state."}, {"title": "Combination, Decomposition, Displacement and Combustion Reactions .txt", "text": "So this is a single display for reaction in which our Mg kicks off this H, forming our reactant, and this H combines with another H forming a diatomic gas."}, {"title": "Combination, Decomposition, Displacement and Combustion Reactions .txt", "text": "Now let's look at a double displacement or a metaphor reaction."}, {"title": "Combination, Decomposition, Displacement and Combustion Reactions .txt", "text": "Now, we have reactance A and B react with reactants CD."}, {"title": "Combination, Decomposition, Displacement and Combustion Reactions .txt", "text": "What happens now is our C displaces this B kicks off this B, forming a bond with a, and at the same time, this B kicks off this C, forming a bond with D. And what we get is the following."}, {"title": "Combination, Decomposition, Displacement and Combustion Reactions .txt", "text": "Or an example of this is the following."}, {"title": "Combination, Decomposition, Displacement and Combustion Reactions .txt", "text": "Now, notice what happened."}, {"title": "Combination, Decomposition, Displacement and Combustion Reactions .txt", "text": "This hydroxide in our first reactant kicked off this so four molecule, forming a bond with H and forming our first product, our water molecule."}, {"title": "Combination, Decomposition, Displacement and Combustion Reactions .txt", "text": "Likewise, this K molecule bonded with the molecule that got kicked off this so four."}, {"title": "Combination, Decomposition, Displacement and Combustion Reactions .txt", "text": "So this so four molecule at the same time kicked off this oh or replaced this oh and bonded with H. And we got K two So four."}, {"title": "Combination, Decomposition, Displacement and Combustion Reactions .txt", "text": "So this is an example of a metaphosis or a double displacement reaction."}, {"title": "Combination, Decomposition, Displacement and Combustion Reactions .txt", "text": "Now, the last type of reaction we're going to look at is called a combustion reaction."}, {"title": "Combination, Decomposition, Displacement and Combustion Reactions .txt", "text": "And in this reaction, hydrocarbons are burned in the presence of diatomic gas or diatomic oxygen gas to form carbon dioxide and water molecules."}, {"title": "Combination, Decomposition, Displacement and Combustion Reactions .txt", "text": "Now, a common example is burning of methane ch four, where our X is one and Y is four in the presence of oxygen."}, {"title": "Combination, Decomposition, Displacement and Combustion Reactions .txt", "text": "And heat from the triangle symbolizes heat to form carbon dioxide and water molecules."}, {"title": "Combination, Decomposition, Displacement and Combustion Reactions .txt", "text": "Now, other types of reactions exist."}, {"title": "Combination, Decomposition, Displacement and Combustion Reactions .txt", "text": "Let's look at some of them."}, {"title": "Combination, Decomposition, Displacement and Combustion Reactions .txt", "text": "Reduce reactions or oxidation reduction reactions in which the oxidation states of atoms change."}, {"title": "Combination, Decomposition, Displacement and Combustion Reactions .txt", "text": "Acid based reactions, hydrolysis reactions and isomerization reaction are very common examples of some other types of chemical reactions."}, {"title": "Combination, Decomposition, Displacement and Combustion Reactions .txt", "text": "Now, note that a certain reaction can be labeled as more than one."}, {"title": "Combination, Decomposition, Displacement and Combustion Reactions .txt", "text": "In other words, let's look at the following decomposition reaction."}, {"title": "Combination, Decomposition, Displacement and Combustion Reactions .txt", "text": "This decomposition reaction is also an oxidation reduction reaction because our O gets oxidized while our H gets reduced."}, {"title": "Combination, Decomposition, Displacement and Combustion Reactions .txt", "text": "In other words, in this molecule, our O has an oxidation state of negative two."}, {"title": "Combination, Decomposition, Displacement and Combustion Reactions .txt", "text": "And here our O has an oxidation state of zero."}, {"title": "Combination, Decomposition, Displacement and Combustion Reactions .txt", "text": "So if it goes from negative two to zero, it's oxidized, while this guy goes from positive one to zero."}, {"title": "Combination, Decomposition, Displacement and Combustion Reactions .txt", "text": "So it's reduced, it gains electrons."}, {"title": "Combination, Decomposition, Displacement and Combustion Reactions .txt", "text": "So this reaction is not only a decomposition reaction, but also a reduction reaction."}, {"title": "Combination, Decomposition, Displacement and Combustion Reactions .txt", "text": "Likewise, let's look at this double displacement or a metaphor reaction."}, {"title": "Combination, Decomposition, Displacement and Combustion Reactions .txt", "text": "Now, notice this guy."}, {"title": "Combination, Decomposition, Displacement and Combustion Reactions .txt", "text": "We have a base potassium hydroxide react with this acid."}, {"title": "Combination, Decomposition, Displacement and Combustion Reactions .txt", "text": "That means this guy is not only a double displacement reaction or a metastasis reaction, it's also an acid based reaction."}, {"title": "Combination, Decomposition, Displacement and Combustion Reactions .txt", "text": "Now, let's look at the reverse of this guy."}, {"title": "Combination, Decomposition, Displacement and Combustion Reactions .txt", "text": "The reverse of this guy is actually a hydrolysis reaction because we have water that act as a nucleophile, displacing one of these molecules forming our product."}, {"title": "Combination, Decomposition, Displacement and Combustion Reactions .txt", "text": "So if we go in the reverse direction this way, this is a hydraulic reaction."}, {"title": "Combination, Decomposition, Displacement and Combustion Reactions .txt", "text": "So the point is, reactions could be more than one."}, {"title": "Evaporation and Condensation.txt", "text": "Evaporation is the process by which liquid molecules gain enough kinetic energy to escape the liquid state and become a gas molecule."}, {"title": "Evaporation and Condensation.txt", "text": "Now."}, {"title": "Evaporation and Condensation.txt", "text": "Condensation is the opposite."}, {"title": "Evaporation and Condensation.txt", "text": "It's the process by which gas molecules hit the liquid, lose kinetic energy, and get stuck in a liquid."}, {"title": "Evaporation and Condensation.txt", "text": "Now, these two processes occur naturally at the surface of a liquid."}, {"title": "Evaporation and Condensation.txt", "text": "Suppose I take a liquid and examine the surface of that liquid."}, {"title": "Evaporation and Condensation.txt", "text": "What I will see is a line of molecules connected together by intermolecular bonds or non covalent bonds."}, {"title": "Evaporation and Condensation.txt", "text": "Now, if I somehow increase the kinetic energy of these molecules, what will happen?"}, {"title": "Evaporation and Condensation.txt", "text": "Well, if one of these molecules gained enough kinetic energy, that energy will be able to overcome the energy due to the bonding."}, {"title": "Evaporation and Condensation.txt", "text": "And this will allow the molecule to escape into the space above."}, {"title": "Evaporation and Condensation.txt", "text": "So that means if I somehow increase the kinetic energy of this system, evaporation will occur."}, {"title": "Evaporation and Condensation.txt", "text": "And if I let them evaporate and then I open, I should hear a hissing sound."}, {"title": "Evaporation and Condensation.txt", "text": "So let's try to increase the kinetic energy of this system by shaking it."}, {"title": "Evaporation and Condensation.txt", "text": "If I shake this, a lot of the molecules are on the surface and within will gain enough kinetic energy, will escape into the gas phase."}, {"title": "Evaporation and Condensation.txt", "text": "And if right, then I open this, I should hear the gas molecules escaping."}, {"title": "Evaporation and Condensation.txt", "text": "So I should hear a hissing sound."}, {"title": "Evaporation and Condensation.txt", "text": "So let's try to shake this."}, {"title": "Evaporation and Condensation.txt", "text": "And that hissing sound was because of the escaping molecule."}, {"title": "Evaporation and Condensation.txt", "text": "So I shook it."}, {"title": "Evaporation and Condensation.txt", "text": "I increased kinetic energy."}, {"title": "Evaporation and Condensation.txt", "text": "A lot of the molecules escaped into this space."}, {"title": "Evaporation and Condensation.txt", "text": "Here."}, {"title": "Evaporation and Condensation.txt", "text": "When I opened it, it evaporated."}, {"title": "Evaporation and Condensation.txt", "text": "And the hissing sound was due to the evaporation."}, {"title": "Evaporation and Condensation.txt", "text": "Now, another way that water can be represented is this way."}, {"title": "Evaporation and Condensation.txt", "text": "H 20 in a liquid state evaporates into H two and a gas state and H so in a gas state, condenses into H 20 in a liquid state."}, {"title": "Evaporation and Condensation.txt", "text": "Now in a closed container."}, {"title": "Evaporation and Condensation.txt", "text": "Eventually, if I leave this alone, this will form Dynamic Equilibrium."}, {"title": "Evaporation and Condensation.txt", "text": "Or it will achieve Dynamic Equilibrium."}, {"title": "Evaporation and Condensation.txt", "text": "And what that simply means is the rate at which the molecules are evaporating is equal to the rate at which they are condensing."}, {"title": "Evaporation and Condensation.txt", "text": "And so the volume at that point will remain the same."}, {"title": "Evaporation and Condensation.txt", "text": "So why is it that puddles found outside evaporate completely?"}, {"title": "Evaporation and Condensation.txt", "text": "All the water eventually goes away."}, {"title": "Evaporation and Condensation.txt", "text": "Well, why is that?"}, {"title": "Evaporation and Condensation.txt", "text": "If eventually, the water molecules found the puddle should be in dynamic equilibrium with the gas molecules above well, the answer is that's because this system is not a closed system."}, {"title": "Evaporation and Condensation.txt", "text": "It's an open system and molecules are allowed to leave."}, {"title": "Evaporation and Condensation.txt", "text": "For example, suppose our dynamic equilibrium is reached."}, {"title": "Evaporation and Condensation.txt", "text": "And so we have a bunch of water molecules above, floating above."}, {"title": "Evaporation and Condensation.txt", "text": "Now, wind, for example, can blow these molecules away."}, {"title": "Evaporation and Condensation.txt", "text": "And if it blows the molecules away, these guys will go away."}, {"title": "Evaporation and Condensation.txt", "text": "And so our H 20 in the gas state will decrease."}, {"title": "Evaporation and Condensation.txt", "text": "And this will shift equilibrium."}, {"title": "Evaporation and Condensation.txt", "text": "This way."}, {"title": "Evaporation and Condensation.txt", "text": "So these guys will continue to evaporate."}, {"title": "Evaporation and Condensation.txt", "text": "The wind will continue belongs in a way."}, {"title": "Evaporation and Condensation.txt", "text": "And eventually, every single molecule will evaporate."}, {"title": "Evaporation and Condensation.txt", "text": "Now, let's look at the boiling or the Boiling Point."}, {"title": "Evaporation and Condensation.txt", "text": "The Boiling Point is the temperature at which the molecules in the liquid gain enough kinetic energy."}, {"title": "Evaporation and Condensation.txt", "text": "And now, I'm not only talking about the molecules on the surface of the water."}, {"title": "Evaporation and Condensation.txt", "text": "Now I'm talking all the molecules found within the entire system gain enough kinetic energy."}, {"title": "Evaporation and Condensation.txt", "text": "So when you boil something, you see bubbles forming from the inside that travel to the up."}, {"title": "Evaporation and Condensation.txt", "text": "It's the outside."}, {"title": "Evaporation and Condensation.txt", "text": "And that's because those molecules found inside gain enough kinetic energy, they become gas molecules, and they travel up."}, {"title": "Evaporation and Condensation.txt", "text": "The Boiling point is also the point at which vapor pressure created by the liquid is equal to or greater than the total pressure found above the system."}, {"title": "Evaporation and Condensation.txt", "text": "So the atmospheric pressure."}, {"title": "Evaporation and Condensation.txt", "text": "So, for example, suppose this is our system and this is our vapor pressure created by the system, and this is our vapor, our pressure, our atmospheric pressure."}, {"title": "Evaporation and Condensation.txt", "text": "Now, if our atmospheric pressure is greater than our vapor pressure, pressure created by a liquid, the vapor pressure will not allow these molecules to escape."}, {"title": "Evaporation and Condensation.txt", "text": "They will push down on them."}, {"title": "Evaporation and Condensation.txt", "text": "However, if the two pressures are equal or if this pressure is greater, these molecules will be able to fly out."}, {"title": "Evaporation and Condensation.txt", "text": "And this is called the Boiling Point, or simply boiling."}, {"title": "Colligative Properties .txt", "text": "So in liquid solutions solve particles or ions disrupt the noncovalent solvent solvent tractions, thereby creating changes in various properties of the pure solvent."}, {"title": "Colligative Properties .txt", "text": "For example, if a solvent is added to a pure substance, the boiling point is higher and the melting point is lower than that of the pure substance."}, {"title": "Colligative Properties .txt", "text": "How much these properties change depend on the concentration of the solute use."}, {"title": "Colligative Properties .txt", "text": "Colligative properties are those properties that depend solely on the concentration of the solid use."}, {"title": "Colligative Properties .txt", "text": "They depend on the number or amount of solid particles used."}, {"title": "Colligative Properties .txt", "text": "They don't depend on the nature or type of particle use."}, {"title": "Colligative Properties .txt", "text": "Now, four major colligator properties are known vapor pressure, osmotic pressure, boiling point elevation, and melting point depression."}, {"title": "Colligative Properties .txt", "text": "I'm going to briefly talk about the first collage of property, vapor pressure."}, {"title": "Colligative Properties .txt", "text": "If you want to go into more detail about vapor pressure, check out my link below."}, {"title": "Colligative Properties .txt", "text": "So vapor pressure is simply the pressure due to the gas molecules found in dynamic equilibrium with their liquid molecules."}, {"title": "Colligative Properties .txt", "text": "Now, we see that adding non volatile solute decreases vapor pressure according to Rolls Law."}, {"title": "Colligative Properties .txt", "text": "Now, if you want to learn more about Rolls Law, check out my link below."}, {"title": "Colligative Properties .txt", "text": "Now, recall that a non volatile solute is a solid that will not evaporate."}, {"title": "Colligative Properties .txt", "text": "So let's see two systems."}, {"title": "Colligative Properties .txt", "text": "We have two systems."}, {"title": "Colligative Properties .txt", "text": "The first system is a system before we add our non volatile solute."}, {"title": "Colligative Properties .txt", "text": "The second system is after the addition of the non volatile solid."}, {"title": "Colligative Properties .txt", "text": "Before addition, a certain vapor pressure is created due to the molecules found in space above."}, {"title": "Colligative Properties .txt", "text": "After addition, some of the solid molecules will be replaced by the non volatile cellulose, and so less will evaporate, and therefore the vapor pressure will be less."}, {"title": "Colligative Properties .txt", "text": "Now, adding volatile cells or molecules that do evaporate increases vapor pressure according to a modified version of Rolls Law."}, {"title": "Colligative Properties .txt", "text": "And that's simply because now we have the solid molecules evaporating and the volatile solid molecules evaporating."}, {"title": "Colligative Properties .txt", "text": "So the final pressure is the sum of the two pressures."}, {"title": "Colligative Properties .txt", "text": "The second collage of property is called the boiling point."}, {"title": "Colligative Properties .txt", "text": "The boiling point is the temperature at which the liquid molecules have enough kinetic energy to escape into the gas state."}, {"title": "Colligative Properties .txt", "text": "Now, this occurs when the vapor pressure, the liquid, equals the atmospheric pressure."}, {"title": "Colligative Properties .txt", "text": "So we see that the boiling point is related to that vapor pressure."}, {"title": "Colligative Properties .txt", "text": "Adding non volatile solution lowers vapor pressure."}, {"title": "Colligative Properties .txt", "text": "And now a higher temperature is required to raise our vapor pressure to that final atmospheric pressure."}, {"title": "Colligative Properties .txt", "text": "So more energy is required."}, {"title": "Colligative Properties .txt", "text": "In fact, we could use a formula to find the change in the boiling point."}, {"title": "Colligative Properties .txt", "text": "So change in boiling point is equal to a constant KB, which is related to the substance being boiled times."}, {"title": "Colligative Properties .txt", "text": "The morality so moles over a kilogram of solid times I I is called vonkov factor, and this is the number of particles a single solid molecule dissociates into."}, {"title": "Colligative Properties .txt", "text": "So if our solid is sodium chloride, we see that sodium chloride dissociates into exactly two particles."}, {"title": "Colligative Properties .txt", "text": "So our eye in an ideal solution will be two."}, {"title": "Colligative Properties .txt", "text": "In a non ideal solution, there is Something Called ion pairing or the momentary aggregation of ions in a solution."}, {"title": "Colligative Properties .txt", "text": "And this will cause I to slightly lower."}, {"title": "Colligative Properties .txt", "text": "And that means, in an ideal solution, this will be two."}, {"title": "Colligative Properties .txt", "text": "In a non ideal solution, this will be slightly below two."}, {"title": "Colligative Properties .txt", "text": "The third color gate of property is called a freezing point."}, {"title": "Colligative Properties .txt", "text": "Or the melting point."}, {"title": "Colligative Properties .txt", "text": "This is the temperature at which the liquid molecules lose the kinetic energy and cannot sustain the liquid state."}, {"title": "Colligative Properties .txt", "text": "And they form a crystalline structure called a solid."}, {"title": "Colligative Properties .txt", "text": "And a freezing or melting point is not related to vigor pressure the same way that boiling points are."}, {"title": "Colligative Properties .txt", "text": "By adding a solid or an impurity to a pure substance, we increase entropy and make it difficult to form a crystal structure."}, {"title": "Colligative Properties .txt", "text": "Therefore, more energy needs to be taken away from our system."}, {"title": "Colligative Properties .txt", "text": "And this means that our freezing and melting point lowers."}, {"title": "Colligative Properties .txt", "text": "Now that melt by which our freezing and melting point lowers can be found by a similar formula."}, {"title": "Colligative Properties .txt", "text": "The change in temperature is equal to a new constant that depends on the substance being melted or frozen."}, {"title": "Colligative Properties .txt", "text": "Times the morality of our substance."}, {"title": "Colligative Properties .txt", "text": "Times I the number of particles a soluble dissociates into."}, {"title": "Colligative Properties .txt", "text": "Now we have to be careful with freezing point depression because adding a salute to a pure substance will only decrease the freezing point to a certain extent."}, {"title": "Colligative Properties .txt", "text": "Eventually our solvent will become our impurity."}, {"title": "Colligative Properties .txt", "text": "Because if we add enough solute, the amount of solute will surpass the amount of solvent."}, {"title": "Colligative Properties .txt", "text": "And when that happens, adding an immortal solute will actually make our freezing point rise and our melting point rise."}, {"title": "Colligative Properties .txt", "text": "The fourth Caligra property is called astronomic pressure."}, {"title": "Colligative Properties .txt", "text": "Asthmatic pressure is a tendency of water or some other solvent to flow into an area with a higher solute concentration."}, {"title": "Colligative Properties .txt", "text": "Now, to demonstrate as much like pressure, let's build a system."}, {"title": "Colligative Properties .txt", "text": "In this system, we have a cell that's embellished in a semipermeable membrane."}, {"title": "Colligative Properties .txt", "text": "Now, this membrane allows the flow of water, but it does not allow any site molecules to pass through."}, {"title": "Colligative Properties .txt", "text": "Now, on the outside, we have many more site molecules than on the inside."}, {"title": "Colligative Properties .txt", "text": "So let's see what entropy tells us about such a system."}, {"title": "Colligative Properties .txt", "text": "Well, entropy dictates that a system will only strive to even out."}, {"title": "Colligative Properties .txt", "text": "And that means in this system, the site molecules will want to move inside the cell."}, {"title": "Colligative Properties .txt", "text": "But remember, because this is semipermeable membrane side molecules will not be able to go inside."}, {"title": "Colligative Properties .txt", "text": "And that means instead, water will try to even out the system and water will flow from a lower concentration to a higher salary of concentration."}, {"title": "Colligative Properties .txt", "text": "So we can define as much as I pressure in a second way."}, {"title": "Colligative Properties .txt", "text": "Astronic pressure is the pressure that needs to be applied to a membrane to stop the flow of solvent into an area of a higher solid concentration."}, {"title": "Colligative Properties .txt", "text": "So whenever we talk about an ideal solution that has a very low solid concentration, we can find osmotic pressure on one side of the equation or on one side of the membrane by using this formula."}, {"title": "Colligative Properties .txt", "text": "And this formula states that osmotic pressure is equal to Bonhopper, which is the number of particles a single molecule or a single site molecule breaks into times molarity of our solution times the gas constant or r times temperature in Kelvin."}, {"title": "Colligative Properties .txt", "text": "Now, now that we talk about osmotic pressure, we also talk about osmotic potential."}, {"title": "Colligative Properties .txt", "text": "Now, any pure substance, such as pure water, is automatically given an asthmatic potential of zero and any impure substance."}, {"title": "Colligative Properties .txt", "text": "So if we add a solution to water, we give it an asthmatic potential of less than deer, so it has a negative asthmatic potential."}, {"title": "Colligative Properties .txt", "text": "And we define the flow of a solvent from a high asthmatic potential to a low asthmatic potential."}, {"title": "Colligative Properties .txt", "text": "So since the outside has many more site molecules, it has a more negative asthmatic potential."}, {"title": "Colligative Properties .txt", "text": "And that means water will flow from a lower asmatic potential to a high asmatic potential or from the inside to the outside."}, {"title": "Balancing Redox Reactions .txt", "text": "Going from an unbalanced redox reaction to a balanced net redox reaction is not always an easy process."}, {"title": "Balancing Redox Reactions .txt", "text": "Now, equations for redox reactions often involve water molecules, hydronium molecules and hydroxide molecules."}, {"title": "Balancing Redox Reactions .txt", "text": "And therefore, determining the number of these molecules in a balanced equation can be very tedious."}, {"title": "Balancing Redox Reactions .txt", "text": "Fortunately, a systematic approach exists to finding the balanced redox reactions and I've outlined seven steps that you can follow when determining or balancing redox reactions."}, {"title": "Balancing Redox Reactions .txt", "text": "So let's see these steps."}, {"title": "Balancing Redox Reactions .txt", "text": "In the first step, you basically have to recognize what atom is oxidized and what atom is reduced."}, {"title": "Balancing Redox Reactions .txt", "text": "Next, you break down the unbalanced reaction into the two half reactions an oxidation reaction and a reduction reaction."}, {"title": "Balancing Redox Reactions .txt", "text": "In the third step, you have to balance atoms in each reaction."}, {"title": "Balancing Redox Reactions .txt", "text": "So in the reduction reaction and the oxidation reaction and the atoms you're balancing are all the atoms other than oxygen and hydrogen."}, {"title": "Balancing Redox Reactions .txt", "text": "Next, you have to balance the oxygen by adding water and hydrogen by adding H plus ions."}, {"title": "Balancing Redox Reactions .txt", "text": "Now, this only works for acidic solutions."}, {"title": "Balancing Redox Reactions .txt", "text": "In basic solutions, you balance the H atoms, the hydrogen atoms by adding oh minus."}, {"title": "Balancing Redox Reactions .txt", "text": "So by adding hydroxide ions in the fifth step you balance the charge by adding electrons to one side."}, {"title": "Balancing Redox Reactions .txt", "text": "Remember, charge is concerned so whatever charge is lost must be gained."}, {"title": "Balancing Redox Reactions .txt", "text": "So that's why you need to balance the charge by adding electrons to one side of the reaction."}, {"title": "Balancing Redox Reactions .txt", "text": "Next, you multiply each half reaction by appropriate factor so that electrons gain equals electrons lost."}, {"title": "Balancing Redox Reactions .txt", "text": "Once again, this comes from the conservation of energy or the conservation of charge."}, {"title": "Balancing Redox Reactions .txt", "text": "In the final step, you basically add the two half reactions and you check to make sure that they are, in fact, balanced."}, {"title": "Balancing Redox Reactions .txt", "text": "So in the next lecture, we're going to look at this unbalanced equation and we're going to follow these steps and balance it and find the final balance net reduction reaction."}, {"title": "Mass percent example #2 .txt", "text": "In this problem, we have ten moles of water in a beaker."}, {"title": "Mass percent example #2 .txt", "text": "We need to find the number of moles of sodium chloride that we need to add to our ten moles of water to create a 5% biomass solution of sodium chloride."}, {"title": "Mass percent example #2 .txt", "text": "The first step is to find the molecular weight of water and this can be done by adding the atomic weight of oxygen plus two times the atomic weight of h to leo, a subscript of two."}, {"title": "Mass percent example #2 .txt", "text": "So two times 1 gram per mole plus 16 grams/mol gives us 18 grams/mol of water."}, {"title": "Mass percent example #2 .txt", "text": "Now we can use this molecular mass, we can multiply that by ten moles to get the amount in grams of water in our solution."}, {"title": "Mass percent example #2 .txt", "text": "So 18 times ten gives us 180."}, {"title": "Mass percent example #2 .txt", "text": "The moles cancel, we're left with grams."}, {"title": "Mass percent example #2 .txt", "text": "So 180 grams of water in our beaker."}, {"title": "Mass percent example #2 .txt", "text": "Now we know we want to create a 5% bimass solution of sodium chloride, so we use the formula 5% is equal to the number of sodium chloride we need to add in terms of grams divided by the total number of grams."}, {"title": "Mass percent example #2 .txt", "text": "So 180 grams of water that we already have, plus the x."}, {"title": "Mass percent example #2 .txt", "text": "The x is the number of sodium chloride in grams that we need to add multiply the whole thing by 100."}, {"title": "Mass percent example #2 .txt", "text": "This is simply the formula for mass percentage."}, {"title": "Mass percent example #2 .txt", "text": "Next we do a little algebra."}, {"title": "Mass percent example #2 .txt", "text": "We bring the 100 over."}, {"title": "Mass percent example #2 .txt", "text": "So we divide five by 100, get 0.5,\nthen we bring the bottom over, multiply this whole bottom by 0.5, so we get 0.05 times 180 plus x."}, {"title": "Mass percent example #2 .txt", "text": "When we multiply this out, we get nine plus 0.5 x."}, {"title": "Mass percent example #2 .txt", "text": "We equate that to x because the x was left on the other side."}, {"title": "Mass percent example #2 .txt", "text": "And now we simply solve for x and we get nine equals zero point 95 x."}, {"title": "Mass percent example #2 .txt", "text": "We divide by zero point 95 x and we get 9.47 grams of sodium chloride that we need to add to the solution of ten moles to get a 5% bimass solution of sodium chloride."}, {"title": "Mass percent example #2 .txt", "text": "The final step is to find the number of moles of sodium chloride."}, {"title": "Mass percent example #2 .txt", "text": "So we have the number of grams we need to add."}, {"title": "Mass percent example #2 .txt", "text": "But our question asks us to find the number of moles."}, {"title": "Mass percent example #2 .txt", "text": "To find that, we need to find the molecular weight of sodium chloride."}, {"title": "Mass percent example #2 .txt", "text": "To find the molecular weight of sodium chloride, we simply add the atomic weights of sodium and chloride."}, {"title": "Mass percent example #2 .txt", "text": "So 23 grams/mol plus 35.5\ngrams/mol gives us 58.5 grams/mol."}, {"title": "Mass percent example #2 .txt", "text": "This is a molecular weight of sodium chloride."}, {"title": "Mass percent example #2 .txt", "text": "Now, to find a number of moles, we divide our molecular weight or we divide our amount that we have by our molecular weight."}, {"title": "Mass percent example #2 .txt", "text": "The grams cancel, the moles go on top."}, {"title": "Mass percent example #2 .txt", "text": "So 9.47\ndivided by 58.5 gives us 0.16 moles of sodium chloride."}, {"title": "Mass percent example #2 .txt", "text": "That lead after our solution to create a 5% bimass solution of sodium chloride."}, {"title": "Arrhenius, Bronsted-Lowry Example and Lecids Acids and Bases .txt", "text": "In this lecture, we're going to look at the three types of Acid Bases that exist in a reaction iranius acid bases, Lewis acid bases, and Bronze Larry acid Bases."}, {"title": "Arrhenius, Bronsted-Lowry Example and Lecids Acids and Bases .txt", "text": "Now, Arrangeous, acids are those compounds that produce Hydride ions in water or they increase the concentration of plus ion it's found in water."}, {"title": "Arrhenius, Bronsted-Lowry Example and Lecids Acids and Bases .txt", "text": "So for example, let's look at HCL."}, {"title": "Arrhenius, Bronsted-Lowry Example and Lecids Acids and Bases .txt", "text": "HCL dissociates in water into an H plus ion and a chloride ion."}, {"title": "Arrhenius, Bronsted-Lowry Example and Lecids Acids and Bases .txt", "text": "And that means because HCL increases the concentration of our H plus ions found in water, by definition, HCL must be an Iranian acid."}, {"title": "Arrhenius, Bronsted-Lowry Example and Lecids Acids and Bases .txt", "text": "Now, Iranian bases are those substances that increase oh concentration in water."}, {"title": "Arrhenius, Bronsted-Lowry Example and Lecids Acids and Bases .txt", "text": "So for example, let's look at sodium Hydroxide."}, {"title": "Arrhenius, Bronsted-Lowry Example and Lecids Acids and Bases .txt", "text": "Sodium Hydroxide, when mixed with water, dissociates into sodium in an oh ion."}, {"title": "Arrhenius, Bronsted-Lowry Example and Lecids Acids and Bases .txt", "text": "And that means it increases the concentration of our oh ions found in water."}, {"title": "Arrhenius, Bronsted-Lowry Example and Lecids Acids and Bases .txt", "text": "Therefore, this guide by the submission must be an Iranius base."}, {"title": "Arrhenius, Bronsted-Lowry Example and Lecids Acids and Bases .txt", "text": "Now, Arrangeous Aspen bases are always found in water that's by definition, whenever we talk about our radius acid bases, we talk about solutions in which our solvent is water."}, {"title": "Arrhenius, Bronsted-Lowry Example and Lecids Acids and Bases .txt", "text": "So let's look at this reaction again."}, {"title": "Arrhenius, Bronsted-Lowry Example and Lecids Acids and Bases .txt", "text": "So we know that HCL, when mixed in water, dissociates into a Hydride ion and a chloride ion."}, {"title": "Arrhenius, Bronsted-Lowry Example and Lecids Acids and Bases .txt", "text": "So now we have a solution that contains a bunch of H plus ions flowing around next to water."}, {"title": "Arrhenius, Bronsted-Lowry Example and Lecids Acids and Bases .txt", "text": "So what actually happens is a base pair or a pair of electrons down on the water grabs the H ion, producing hydronium ion."}, {"title": "Arrhenius, Bronsted-Lowry Example and Lecids Acids and Bases .txt", "text": "So actually, the Hydride ion produced by an Iranius acid is always associated with a hydronium molecule."}, {"title": "Arrhenius, Bronsted-Lowry Example and Lecids Acids and Bases .txt", "text": "And that's because our solvent is always water."}, {"title": "Arrhenius, Bronsted-Lowry Example and Lecids Acids and Bases .txt", "text": "According to the Iranian acid based concept in Aqueous Solutions, the hydronium ions are responsible for acidic properties and the oh ions are responsible for the basic properties."}, {"title": "Arrhenius, Bronsted-Lowry Example and Lecids Acids and Bases .txt", "text": "Now, one problem with such a definition exists molecules such as ammonia, molecules that produce basic solutions and react with acids and yet they have no oh ions."}, {"title": "Arrhenius, Bronsted-Lowry Example and Lecids Acids and Bases .txt", "text": "So if we look at the structure of NH three Ammonium, we see that it contains three HS, one N and a pair of electrons."}, {"title": "Arrhenius, Bronsted-Lowry Example and Lecids Acids and Bases .txt", "text": "Clearly, it has no oh ions."}, {"title": "Arrhenius, Bronsted-Lowry Example and Lecids Acids and Bases .txt", "text": "So according to our Iranians Acid Based definition, this cannot be a base, yet it has basic properties."}, {"title": "Arrhenius, Bronsted-Lowry Example and Lecids Acids and Bases .txt", "text": "So this definition isn't that good."}, {"title": "Arrhenius, Bronsted-Lowry Example and Lecids Acids and Bases .txt", "text": "So they come up with a better definition, a definition that includes many more bases and many more acids."}, {"title": "Arrhenius, Bronsted-Lowry Example and Lecids Acids and Bases .txt", "text": "And this concept is called the Broccolari acid based concept."}, {"title": "Arrhenius, Bronsted-Lowry Example and Lecids Acids and Bases .txt", "text": "So Broccollory bases are those molecules that can accept a Hydride ion using a lone pair of electrons."}, {"title": "Arrhenius, Bronsted-Lowry Example and Lecids Acids and Bases .txt", "text": "So let's look at the reaction of Ammonia and water."}, {"title": "Arrhenius, Bronsted-Lowry Example and Lecids Acids and Bases .txt", "text": "So in ammonia, we have an extra pair of electrons."}, {"title": "Arrhenius, Bronsted-Lowry Example and Lecids Acids and Bases .txt", "text": "And in fact, this pair of electrons will take away an H ion from the water molecule and this will produce Ammonium and hydroxide."}, {"title": "Arrhenius, Bronsted-Lowry Example and Lecids Acids and Bases .txt", "text": "So by definition, because this guy has an extra pair of electrons, a lone pair of electrons, it acts as a bronzedidlower base."}, {"title": "Arrhenius, Bronsted-Lowry Example and Lecids Acids and Bases .txt", "text": "Now, a Bronzedidloric acid, are those molecules that can donate a Hydride ion."}, {"title": "Arrhenius, Bronsted-Lowry Example and Lecids Acids and Bases .txt", "text": "So, for example, let's look at the reaction of nitric acid and water."}, {"title": "Arrhenius, Bronsted-Lowry Example and Lecids Acids and Bases .txt", "text": "So, nitric acid has an extra ion, extra hydrate ion."}, {"title": "Arrhenius, Bronsted-Lowry Example and Lecids Acids and Bases .txt", "text": "And in fact, the water has an extra pair of electrons that will take away this ion."}, {"title": "Arrhenius, Bronsted-Lowry Example and Lecids Acids and Bases .txt", "text": "And this will produce hydronium ion."}, {"title": "Arrhenius, Bronsted-Lowry Example and Lecids Acids and Bases .txt", "text": "And this ion here, that's negatively charged."}, {"title": "Arrhenius, Bronsted-Lowry Example and Lecids Acids and Bases .txt", "text": "So, by the dimension nitric acid, because it could donate NH, it has an extra H. It act as a bronze of lyric acid."}, {"title": "Arrhenius, Bronsted-Lowry Example and Lecids Acids and Bases .txt", "text": "Now, notice something interesting."}, {"title": "Arrhenius, Bronsted-Lowry Example and Lecids Acids and Bases .txt", "text": "In this reaction, our water acted as an acid, a bronzed larry acid, because it donated NH, right?"}, {"title": "Arrhenius, Bronsted-Lowry Example and Lecids Acids and Bases .txt", "text": "It gave an H to this guy producing ammonium and became hydroxide itself."}, {"title": "Arrhenius, Bronsted-Lowry Example and Lecids Acids and Bases .txt", "text": "So it was a base here I'm sorry, an acid here."}, {"title": "Arrhenius, Bronsted-Lowry Example and Lecids Acids and Bases .txt", "text": "In this reaction, it took away an H.\nAnd because it took away an H, it was acting as a base."}, {"title": "Arrhenius, Bronsted-Lowry Example and Lecids Acids and Bases .txt", "text": "It accepted an age."}, {"title": "Arrhenius, Bronsted-Lowry Example and Lecids Acids and Bases .txt", "text": "So in this case, it was a base."}, {"title": "Arrhenius, Bronsted-Lowry Example and Lecids Acids and Bases .txt", "text": "In this case, it was an acid."}, {"title": "Arrhenius, Bronsted-Lowry Example and Lecids Acids and Bases .txt", "text": "One interesting thing about a water molecule is that under basic conditions, it acts as an acid, and under acidic conditions, it acts as a base."}, {"title": "Arrhenius, Bronsted-Lowry Example and Lecids Acids and Bases .txt", "text": "Our third and final definition of an acid and a base is the most basic definition."}, {"title": "Arrhenius, Bronsted-Lowry Example and Lecids Acids and Bases .txt", "text": "And this concept is called a lewis acidbased concept."}, {"title": "Arrhenius, Bronsted-Lowry Example and Lecids Acids and Bases .txt", "text": "Now, this includes all the bronzed Larry acid bases and many, many more."}, {"title": "Arrhenius, Bronsted-Lowry Example and Lecids Acids and Bases .txt", "text": "So let's look at a lewis acid."}, {"title": "Arrhenius, Bronsted-Lowry Example and Lecids Acids and Bases .txt", "text": "A lewis acid is anything that accepts a lone pair of electrons to form a new bond."}, {"title": "Arrhenius, Bronsted-Lowry Example and Lecids Acids and Bases .txt", "text": "And this bond is usually called a cotton covalent bond."}, {"title": "Arrhenius, Bronsted-Lowry Example and Lecids Acids and Bases .txt", "text": "And we'll see why in a second."}, {"title": "Arrhenius, Bronsted-Lowry Example and Lecids Acids and Bases .txt", "text": "So we have BF three."}, {"title": "Arrhenius, Bronsted-Lowry Example and Lecids Acids and Bases .txt", "text": "Plus an ace that has a lone pair of electrons forms a cordon covalent bond, HBF three."}, {"title": "Arrhenius, Bronsted-Lowry Example and Lecids Acids and Bases .txt", "text": "And it's called Cortis covalent and not Covalent because both electrons come from a single atom."}, {"title": "Arrhenius, Bronsted-Lowry Example and Lecids Acids and Bases .txt", "text": "Remember, in a Covalent bond, one electron comes from here, and one electron comes from here."}, {"title": "Arrhenius, Bronsted-Lowry Example and Lecids Acids and Bases .txt", "text": "But in this case, both electrons come from a single atom."}, {"title": "Arrhenius, Bronsted-Lowry Example and Lecids Acids and Bases .txt", "text": "So let's look at the structural depiction of BF three."}, {"title": "Arrhenius, Bronsted-Lowry Example and Lecids Acids and Bases .txt", "text": "BF three has three HS attached to the boron, and the boron has an empty orbital."}, {"title": "Arrhenius, Bronsted-Lowry Example and Lecids Acids and Bases .txt", "text": "And this empty orbital is what interacts with the lone pair of electrons on our H, forming our corticovalent bond."}, {"title": "Arrhenius, Bronsted-Lowry Example and Lecids Acids and Bases .txt", "text": "So in this case, the BF three accepted the pair of electrons because it had that anti orbital."}, {"title": "Arrhenius, Bronsted-Lowry Example and Lecids Acids and Bases .txt", "text": "So the BF three is our lewis acid."}, {"title": "Arrhenius, Bronsted-Lowry Example and Lecids Acids and Bases .txt", "text": "So another way to talk about a lewis acid is to say that a lewis acid is either neutral or a cation."}, {"title": "Arrhenius, Bronsted-Lowry Example and Lecids Acids and Bases .txt", "text": "In this case, it was neutral that has an empty orbital."}, {"title": "Arrhenius, Bronsted-Lowry Example and Lecids Acids and Bases .txt", "text": "Now let's look at lewis bases."}, {"title": "Arrhenius, Bronsted-Lowry Example and Lecids Acids and Bases .txt", "text": "A lewis base is anything that can donate a pair of electrons to form a new bond, a cordon covalent bond."}, {"title": "Arrhenius, Bronsted-Lowry Example and Lecids Acids and Bases .txt", "text": "Let's look at one of the most basic reactions."}, {"title": "Arrhenius, Bronsted-Lowry Example and Lecids Acids and Bases .txt", "text": "An H atom plus a water molecule gives you a hydronium ion."}, {"title": "Arrhenius, Bronsted-Lowry Example and Lecids Acids and Bases .txt", "text": "So this is a cation that has an empty orbital."}, {"title": "Arrhenius, Bronsted-Lowry Example and Lecids Acids and Bases .txt", "text": "So this must be a lewis acid."}, {"title": "Arrhenius, Bronsted-Lowry Example and Lecids Acids and Bases .txt", "text": "Remember a cation and an empty orbital."}, {"title": "Arrhenius, Bronsted-Lowry Example and Lecids Acids and Bases .txt", "text": "Plus water."}, {"title": "Arrhenius, Bronsted-Lowry Example and Lecids Acids and Bases .txt", "text": "Well, water has what?"}, {"title": "Arrhenius, Bronsted-Lowry Example and Lecids Acids and Bases .txt", "text": "It has a pair of electrons."}, {"title": "Arrhenius, Bronsted-Lowry Example and Lecids Acids and Bases .txt", "text": "It means it can donate a pair of electrons."}, {"title": "Arrhenius, Bronsted-Lowry Example and Lecids Acids and Bases .txt", "text": "So water must be our Lewis base."}, {"title": "Arrhenius, Bronsted-Lowry Example and Lecids Acids and Bases .txt", "text": "And these guys interact to form hydronium ion."}, {"title": "Arrhenius, Bronsted-Lowry Example and Lecids Acids and Bases .txt", "text": "So in this case, in this reaction, this was our Lewis acid, and this was our Lewis base."}, {"title": "Arrhenius, Bronsted-Lowry Example and Lecids Acids and Bases .txt", "text": "So, once again, whenever we talk about Lewis Acid bases, we talk about a transfer of electrons."}, {"title": "Arrhenius, Bronsted-Lowry Example and Lecids Acids and Bases .txt", "text": "Whenever we talk about Bronsted-Lowrey acid bases, we talk about a transfer of hydride ions."}, {"title": "Oxidation Numbers .txt", "text": "Certain reactions, called redox reactions, involve the transfer of electrons from one atom to another."}, {"title": "Oxidation Numbers .txt", "text": "Now, in order to keep track of these electrons, a system was devised in which each atom is assigned an electrical charge."}, {"title": "Oxidation Numbers .txt", "text": "Now, this electrical charge is known as oxidation number or oxidation state of our atom."}, {"title": "Oxidation Numbers .txt", "text": "So oxidation states are just the different possible charge values that one can assign to specific atom."}, {"title": "Oxidation Numbers .txt", "text": "Now, these oxidation states help us keep track of these electrons."}, {"title": "Oxidation Numbers .txt", "text": "But in order to use these oxidation states, we must learn a few rules."}, {"title": "Oxidation Numbers .txt", "text": "Let's look at these rules."}, {"title": "Oxidation Numbers .txt", "text": "So, all atoms in their elemental state are given an oxidation state of zero."}, {"title": "Oxidation Numbers .txt", "text": "There are no exceptions to this rule."}, {"title": "Oxidation Numbers .txt", "text": "So atoms called fluorine always get oxidation states of negative one."}, {"title": "Oxidation Numbers .txt", "text": "There are no exceptions to this rule as well."}, {"title": "Oxidation Numbers .txt", "text": "So atoms called hydrogen are given the oxidation state of plus one."}, {"title": "Oxidation Numbers .txt", "text": "But there's one exception to this rule."}, {"title": "Oxidation Numbers .txt", "text": "They're given oxidation state of negative one."}, {"title": "Oxidation Numbers .txt", "text": "When combined with metals such as, for example, sodium or calcium, the atom oxygen is given to oxidation state of negative two."}, {"title": "Oxidation Numbers .txt", "text": "But there's an exception."}, {"title": "Oxidation Numbers .txt", "text": "It's given oxidation state of negative one when combined in the form H 202."}, {"title": "Oxidation Numbers .txt", "text": "But that's because this rule is more important than this rule."}, {"title": "Oxidation Numbers .txt", "text": "So on this table, every rule that comes before it is more important."}, {"title": "Oxidation Numbers .txt", "text": "For example, this is the most important rule, the second most important rule, third most important rule, and fourth most important rule."}, {"title": "Oxidation Numbers .txt", "text": "So when you're assigning these activation numbers, you must keep that in mind."}, {"title": "Oxidation Numbers .txt", "text": "Now, let's look at a few more guidelines that we can use when assigning oxidation states."}, {"title": "Oxidation Numbers .txt", "text": "Now, this table is meant to be a guideline."}, {"title": "Oxidation Numbers .txt", "text": "It's meant to help you assign oxidation states."}, {"title": "Oxidation Numbers .txt", "text": "They're not rules that will always work."}, {"title": "Oxidation Numbers .txt", "text": "And in fact, the table given before this table is more important."}, {"title": "Oxidation Numbers .txt", "text": "And so it precedes this table."}, {"title": "Oxidation Numbers .txt", "text": "But let's look at the general guidelines."}, {"title": "Oxidation Numbers .txt", "text": "So the group number one, the alkali metals are assigned an oxidation state of plus one."}, {"title": "Oxidation Numbers .txt", "text": "Group number two, the alkali earth metals are assigned oxidation state of plus two."}, {"title": "Oxidation Numbers .txt", "text": "So group number 15, including nitrogen, phosphorus, and so on, are assigned an oxidation state of negative three."}, {"title": "Oxidation Numbers .txt", "text": "Group number 16, including oxygen, sulfur, and so on, are a sign oxidation state of negative two."}, {"title": "Oxidation Numbers .txt", "text": "And finally, halogens, are assigned oxidation state of negative one."}, {"title": "Oxidation Numbers .txt", "text": "Now, let's do a few examples using these guidelines and rules."}, {"title": "Boiling Point Elevation and Freezing Point Depression.txt", "text": "In this example, we begin with 44 grams of ethylene glycol, our solute, 800 water, our solvent."}, {"title": "Boiling Point Elevation and Freezing Point Depression.txt", "text": "We're given the density bar of water to be 1 gram/ML and our constants for boiling and for freezing are 0.5 and 1.8."}, {"title": "Boiling Point Elevation and Freezing Point Depression.txt", "text": "So our goal is to find the final freezing and boiling point of the solution."}, {"title": "Boiling Point Elevation and Freezing Point Depression.txt", "text": "So in our initial condition, we have 800 our salad in our water and the boiling point of water is 100 celsius and deer Celsius."}, {"title": "Boiling Point Elevation and Freezing Point Depression.txt", "text": "Now we want to find what the final freezing and boiling point of our solution is after we mix our solute into the mixture."}, {"title": "Boiling Point Elevation and Freezing Point Depression.txt", "text": "So we expect our boiling point to rise and our freezing point to depress or decrease."}, {"title": "Boiling Point Elevation and Freezing Point Depression.txt", "text": "Because when you add Solutes to pure substances, that decreases vapor pressure."}, {"title": "Boiling Point Elevation and Freezing Point Depression.txt", "text": "And if you want to learn more about vapor pressure and how it affects boiling points or freezing points, check out the video below."}, {"title": "Boiling Point Elevation and Freezing Point Depression.txt", "text": "Now let's get back to our problem."}, {"title": "Boiling Point Elevation and Freezing Point Depression.txt", "text": "So, before we can apply our two formulas for freezing and boiling points, or the change in temperature for freezing boiling points, we have to find the morality."}, {"title": "Boiling Point Elevation and Freezing Point Depression.txt", "text": "Because look, we have the I for both cases, it's simply one."}, {"title": "Boiling Point Elevation and Freezing Point Depression.txt", "text": "We have our constants KB and KF they're given here."}, {"title": "Boiling Point Elevation and Freezing Point Depression.txt", "text": "What we don't have is our molarity."}, {"title": "Boiling Point Elevation and Freezing Point Depression.txt", "text": "So as soon as we find our molarity, we could plug that in into our formulas and we get our results."}, {"title": "Boiling Point Elevation and Freezing Point Depression.txt", "text": "So let's find our morality."}, {"title": "Boiling Point Elevation and Freezing Point Depression.txt", "text": "In step one, we find the numerator of our molarity."}, {"title": "Boiling Point Elevation and Freezing Point Depression.txt", "text": "In step two, we find the denominator of our morality."}, {"title": "Boiling Point Elevation and Freezing Point Depression.txt", "text": "So that means first we have to find the moles of our solute."}, {"title": "Boiling Point Elevation and Freezing Point Depression.txt", "text": "But before we get to the moles of solute, we have to find the molar mass."}, {"title": "Boiling Point Elevation and Freezing Point Depression.txt", "text": "And you'll see why in a second."}, {"title": "Boiling Point Elevation and Freezing Point Depression.txt", "text": "So let's find the molar mass of our ethylene glycol, our solute."}, {"title": "Boiling Point Elevation and Freezing Point Depression.txt", "text": "So basically, we add up the atomic mass of each atom."}, {"title": "Boiling Point Elevation and Freezing Point Depression.txt", "text": "So, since we have two carbon atoms, we multiply two times 12 grams/mol for carbon."}, {"title": "Boiling Point Elevation and Freezing Point Depression.txt", "text": "Since we have two O atoms, we multiply two times 16 grams/mol for oxygen."}, {"title": "Boiling Point Elevation and Freezing Point Depression.txt", "text": "And since we have six H atoms, we multiply six times 1 gram/mol for h and we get all these guys up 62 grams/mol."}, {"title": "Boiling Point Elevation and Freezing Point Depression.txt", "text": "So that's our molar mass of our solute."}, {"title": "Boiling Point Elevation and Freezing Point Depression.txt", "text": "Now, to find the moles of Solute, we take our grams of solute and divide that by molar mass and we should get 44 grams divided by 62 grams."}, {"title": "Boiling Point Elevation and Freezing Point Depression.txt", "text": "The grams cancel moles dose on top and we get zero point 71 moles of our solute."}, {"title": "Boiling Point Elevation and Freezing Point Depression.txt", "text": "So now we have the top component of our mortality."}, {"title": "Boiling Point Elevation and Freezing Point Depression.txt", "text": "Let's find the bottom."}, {"title": "Boiling Point Elevation and Freezing Point Depression.txt", "text": "Remember, it's moles of solute divided by kilogram of solvent."}, {"title": "Boiling Point Elevation and Freezing Point Depression.txt", "text": "To find the kilograms of our solvent, we have to use the density of water, the fact that we have 800."}, {"title": "Boiling Point Elevation and Freezing Point Depression.txt", "text": "Then we have to divide by a thousand because we want to go from grams to kilograms."}, {"title": "Boiling Point Elevation and Freezing Point Depression.txt", "text": "So our density of water times milliliters of solvent divided by 1000."}, {"title": "Boiling Point Elevation and Freezing Point Depression.txt", "text": "Once again, 1000."}, {"title": "Boiling Point Elevation and Freezing Point Depression.txt", "text": "We divide by 1000 because we want to go from grams to kilograms."}, {"title": "Boiling Point Elevation and Freezing Point Depression.txt", "text": "So 1 gram over ML, which is our density times 800 ML over 1000, gives us the MLS cancel grams becomes kilogram because we're dividing by 1000 and that gets us zero 8 solid."}, {"title": "Boiling Point Elevation and Freezing Point Depression.txt", "text": "So now we have our Molarity, namely zero point 71 moles divided by 0.8\nkg, so a bit less than one."}, {"title": "Boiling Point Elevation and Freezing Point Depression.txt", "text": "So we go to our final step."}, {"title": "Boiling Point Elevation and Freezing Point Depression.txt", "text": "In our final step we simply write the formulas for the change in boiling point and changing freezing point when we add a salute."}, {"title": "Boiling Point Elevation and Freezing Point Depression.txt", "text": "So let's find the change in boiling point first."}, {"title": "Boiling Point Elevation and Freezing Point Depression.txt", "text": "Changing boiling point is equal to our constant times molarity times I. I is simply the number of particles that our solid associates into."}, {"title": "Boiling Point Elevation and Freezing Point Depression.txt", "text": "And since this doesn't associate into anything, we simply put I equals one, so this equals zero five."}, {"title": "Boiling Point Elevation and Freezing Point Depression.txt", "text": "Our constant Celsius times kilogram over mole multiplied by zero 71 moles over zero eight our mole ounce the kilograms cancel, the moles cancel, we're left with 44 degrees Celsius."}, {"title": "Boiling Point Elevation and Freezing Point Depression.txt", "text": "So our temperature, our boiling point increases by 00:44 degree Celsius degree and that basically bumps our boiling point up to 100.44\ndegrees Celsius."}, {"title": "Boiling Point Elevation and Freezing Point Depression.txt", "text": "Now our change in freezing point is equal to our constant KF times molarity times i."}, {"title": "Boiling Point Elevation and Freezing Point Depression.txt", "text": "Once again I is one."}, {"title": "Boiling Point Elevation and Freezing Point Depression.txt", "text": "Our molarity stays the same, our constant changes."}, {"title": "Boiling Point Elevation and Freezing Point Depression.txt", "text": "Now we plug in 1.8, we get 1.8\ntimes our molarity and we get approximately 1.6 degrees Celsius."}, {"title": "Boiling Point Elevation and Freezing Point Depression.txt", "text": "And now we have to take this and subtract it from zero and we get negative 1.6\ndegrees Celsius."}, {"title": "Boiling Point Elevation and Freezing Point Depression.txt", "text": "Now once again, if you want to learn why the voiding point increases and phasing point decreases then check out the link below."}, {"title": "Boiling Point Elevation and Freezing Point Depression.txt", "text": "But otherwise this is our final result."}, {"title": "Nernst Equation Part I .txt", "text": "So far we have only spoken about electrochemical cells in which the reactants and products are both at standard state conditions."}, {"title": "Nernst Equation Part I .txt", "text": "This means when I showed you the relationship between the concentration of reactants and products and the electrochemical cells cell voltage I did this on the standard state conditions."}, {"title": "Nernst Equation Part I .txt", "text": "However, most reactions actions do not occur under standard state conditions."}, {"title": "Nernst Equation Part I .txt", "text": "This means we must revisit the topic of the relationship between the concentrations and the cell voltage and adjusted for nonstandard state conditions."}, {"title": "Nernst Equation Part I .txt", "text": "So, to begin, let's first talk about standard state conditions."}, {"title": "Nernst Equation Part I .txt", "text": "So, standard state conditions simply means a concentration of one molar and a pressure of 1 bar and the temperature could be anything."}, {"title": "Nernst Equation Part I .txt", "text": "Normally the temperature is 25 degrees Celsius or 298 degrees Kelvin."}, {"title": "Nernst Equation Part I .txt", "text": "But it could really be anything."}, {"title": "Nernst Equation Part I .txt", "text": "So, in a previous lecture we saw that the relationship between equilibrium constant K on the standard conditions is the following log of base ten of k is equal to number of moles of electrons and times our cell voltage on the same state conditions divided by 0.0592."}, {"title": "Nernst Equation Part I .txt", "text": "Now, this guy is at equilibrium is when our reaction is at equilibrium."}, {"title": "Nernst Equation Part I .txt", "text": "And if our reaction has reactants A and b and C and D which are all in an Aqueous state, then our equilibrium constant expression is the following if k equals the ratio of the concentration of products divided by the ratio of the concentration of reactants."}, {"title": "Nernst Equation Part I .txt", "text": "Now, to begin our process of adjusting for the new relationship between the concentration and the cell potential, let's look at gives free energy."}, {"title": "Nernst Equation Part I .txt", "text": "Now, under nonstandard state conditions we can make an adjustment to gifts free energy formula."}, {"title": "Nernst Equation Part I .txt", "text": "Remember, before under standard state conditions our formula was the following."}, {"title": "Nernst Equation Part I .txt", "text": "It was simply gifts free energy or change in gifts free energy under standard state conditions is equal to negative of this guy."}, {"title": "Nernst Equation Part I .txt", "text": "But now we are not under Stan and state conditions."}, {"title": "Nernst Equation Part I .txt", "text": "And we must make that adjustment."}, {"title": "Nernst Equation Part I .txt", "text": "So, the adjustment is the following."}, {"title": "Nernst Equation Part I .txt", "text": "Now, this guy is now our term used to adjust for non equilibrium and nonstandard state conditions."}, {"title": "Nernst Equation Part I .txt", "text": "Now, this is still our free energy at equilibrium for state and state conditions."}, {"title": "Nernst Equation Part I .txt", "text": "And this is the actual free energy at some point in our reaction."}, {"title": "Nernst Equation Part I .txt", "text": "Now, let's look at this reaction."}, {"title": "Nernst Equation Part I .txt", "text": "Suppose we had some reaction that wasn't at Stan and state condition and that wasn't an equilibrium."}, {"title": "Nernst Equation Part I .txt", "text": "So our reactant A was an acre state, reactant B was an acre state, our product C was also an acrylic state."}, {"title": "Nernst Equation Part I .txt", "text": "And our product D was also an acreage state."}, {"title": "Nernst Equation Part I .txt", "text": "Now, this Q has the same meaning as this K. It's also a constant."}, {"title": "Nernst Equation Part I .txt", "text": "And we can use or develop an expression for this reaction for this Q in the same way that we did here."}, {"title": "Nernst Equation Part I .txt", "text": "And here it is."}, {"title": "Nernst Equation Part I .txt", "text": "So, q is equal to the product of the concentrations of the products divided by the product of the concentrations of reactants."}, {"title": "Nernst Equation Part I .txt", "text": "Now, what happens when these guys begin reacting forming C and D, while the concentration of C and D Begins to Increase."}, {"title": "Nernst Equation Part I .txt", "text": "While the concentration of A and B begins to decrease."}, {"title": "Nernst Equation Part I .txt", "text": "And so our Top begins to increase and bottom Begins to Increase."}, {"title": "Nernst Equation Part I .txt", "text": "Our Q becomes larger."}, {"title": "Nernst Equation Part I .txt", "text": "But notice that according to Lush at Leer Principle, if our concentration of products begin to Increase, what will tend to happen?"}, {"title": "Nernst Equation Part I .txt", "text": "Well, if we have more of this guy equilibrium will slowly begin to shift to the Left."}, {"title": "Nernst Equation Part I .txt", "text": "This is according to Le Chaplier principle."}, {"title": "Nernst Equation Part I .txt", "text": "Now what this equation does is it agrees with Chiplier Principle."}, {"title": "Nernst Equation Part I .txt", "text": "With this idea that if we have more products, our equilibrium will shift this way."}, {"title": "Nernst Equation Part I .txt", "text": "Now let's see how exactly it agrees."}, {"title": "Nernst Equation Part I .txt", "text": "Well, let's look."}, {"title": "Nernst Equation Part I .txt", "text": "This is our change in Gifs free energy at equilibrium at Seven state conditions."}, {"title": "Nernst Equation Part I .txt", "text": "And whenever it's Negative, that means our reaction is product Favored, right?"}, {"title": "Nernst Equation Part I .txt", "text": "It's spontaneous at those conditions."}, {"title": "Nernst Equation Part I .txt", "text": "So if this is A negative term and this is A positive term."}, {"title": "Nernst Equation Part I .txt", "text": "Then together they will be less negative and more positive."}, {"title": "Nernst Equation Part I .txt", "text": "So this term adjusts for lusha clear's principle."}, {"title": "Nernst Equation Part I .txt", "text": "Because look, if our Q Begins to increase when more products are formed, that means Q is say bigger than One."}, {"title": "Nernst Equation Part I .txt", "text": "And whenever we take the natural log of any number that's bigger than One, we get A positive number."}, {"title": "Nernst Equation Part I .txt", "text": "So this whole thing is A positive number."}, {"title": "Nernst Equation Part I .txt", "text": "Because R is positive to constant and T is positive to temperature."}, {"title": "Nernst Equation Part I .txt", "text": "So this guy will be Positive, right?"}, {"title": "Nernst Equation Part I .txt", "text": "That means our equilibrium, some negative number plus A positive number will make A more positive number."}, {"title": "Nernst Equation Part I .txt", "text": "So let's principle says that when we when we form more products, our reaction will shift to the Left."}, {"title": "Nernst Equation Part I .txt", "text": "That's exactly what this guy says as well."}, {"title": "Nernst Equation Part I .txt", "text": "If this is A negative number and you add A positive number to it, we're going to get A more positive result."}, {"title": "Nernst Equation Part I .txt", "text": "More positive, free energy."}, {"title": "Nernst Equation Part I .txt", "text": "And what does gifts free energy tell us when it's positive?"}, {"title": "Nernst Equation Part I .txt", "text": "It tells us our reaction is react in favor."}, {"title": "Nernst Equation Part I .txt", "text": "So this is an equation for gifts free energy under non thin state conditions."}, {"title": "Nernst Equation Part I .txt", "text": "So now we can use this formula."}, {"title": "Nernst Equation Part I .txt", "text": "And in Part C we can plug things in."}, {"title": "Nernst Equation Part I .txt", "text": "Let's look."}, {"title": "Nernst Equation Part I .txt", "text": "So in another lecture we saw that changing gifts the energy on the same and state Conditions is equal to negative number of Moles and of electrons times our Faraday's constant times cell Voltage."}, {"title": "Nernst Equation Part I .txt", "text": "Well, we can write the same equation for non Simmon state Conditions."}, {"title": "Nernst Equation Part I .txt", "text": "Except now we're not using Dot."}, {"title": "Nernst Equation Part I .txt", "text": "Because now we're not at SIM and state conditions."}, {"title": "Nernst Equation Part I .txt", "text": "So Now let's plug these guys in into this formula."}, {"title": "Nernst Equation Part I .txt", "text": "And this is what we get."}, {"title": "Nernst Equation Part I .txt", "text": "Well, we plug this guy in into this guy here and this guy into this guy here."}, {"title": "Nernst Equation Part I .txt", "text": "And we get the following negative N times Friday's constant times E at nonstandard state conditions equals the same thing on the Stale state Conditions."}, {"title": "Nernst Equation Part I .txt", "text": "Which is our Standard state gives fee energy plus this constant here"}, {"title": "Nernst Equation Example .txt", "text": "So in this example, we begin with the following redox reaction."}, {"title": "Nernst Equation Example .txt", "text": "So zinc solid reacts with nickel in the April state to produce zinc in the April state and nickel solid."}, {"title": "Nernst Equation Example .txt", "text": "We are also given our cell potential or cell voltage of our electrochemical cell under stanley conditions of 1 bar pressure and one molar concentration."}, {"title": "Nernst Equation Example .txt", "text": "And this is zero point 51 volts."}, {"title": "Nernst Equation Example .txt", "text": "We're also given the concentrations of nickel of this guy and the concentration of the zinc in the acreage state of this guy."}, {"title": "Nernst Equation Example .txt", "text": "So notice that two and three represent nonstandard conditions."}, {"title": "Nernst Equation Example .txt", "text": "And in fact, our goal is to find the cell potential under these nonstandard state conditions."}, {"title": "Nernst Equation Example .txt", "text": "So whenever we hear the word nonstandard and cell potential, we have to think nurse equation."}, {"title": "Nernst Equation Example .txt", "text": "That's exactly what we do in step two."}, {"title": "Nernst Equation Example .txt", "text": "But before we can use this equation, we have to find our Q."}, {"title": "Nernst Equation Example .txt", "text": "So in step one, that's what we do."}, {"title": "Nernst Equation Example .txt", "text": "Remember, Q is a ratio of the concentration of products over the concentration of reactants."}, {"title": "Nernst Equation Example .txt", "text": "And our expression is similar to K equilibrium constant, except this condition represents a situation that is not an equilibrium."}, {"title": "Nernst Equation Example .txt", "text": "So we basically take our concentration of this guy and divide it by the concentration of reactants of this guy."}, {"title": "Nernst Equation Example .txt", "text": "Now, we don't include this guy or this guy why?"}, {"title": "Nernst Equation Example .txt", "text": "Or because they're in the solid states."}, {"title": "Nernst Equation Example .txt", "text": "Solid atoms or liquid atoms are not included in our expression."}, {"title": "Nernst Equation Example .txt", "text": "Only gas molecules and aqueous atoms are included in our expression."}, {"title": "Nernst Equation Example .txt", "text": "And notice that we're giving these guys, right?"}, {"title": "Nernst Equation Example .txt", "text": "This guy is 0.5\nmolar, while this guy is five molar."}, {"title": "Nernst Equation Example .txt", "text": "So we divide 0.5 divided by five."}, {"title": "Nernst Equation Example .txt", "text": "That gives us one over 100, which is 0.1 the M cancel."}, {"title": "Nernst Equation Example .txt", "text": "So this guy is unitless."}, {"title": "Nernst Equation Example .txt", "text": "And recall what Q tells us about our reaction."}, {"title": "Nernst Equation Example .txt", "text": "If Q is less than one, that means we have a lot of this guy and none of this guy."}, {"title": "Nernst Equation Example .txt", "text": "In this situation, for every one of this guy, for every one of the in the acre state, we have 100 of nickels in the Aqueous state."}, {"title": "Nernst Equation Example .txt", "text": "And that means we have much more reactants than products."}, {"title": "Nernst Equation Example .txt", "text": "And according to Leslie Clay's principle, this reaction will be very product favorite."}, {"title": "Nernst Equation Example .txt", "text": "It will want to form the products."}, {"title": "Nernst Equation Example .txt", "text": "So that's what Q tells us."}, {"title": "Nernst Equation Example .txt", "text": "Let's see what we can deduce from number two and number two."}, {"title": "Nernst Equation Example .txt", "text": "We're going to find the cell potential."}, {"title": "Nernst Equation Example .txt", "text": "Now, e is equal to e this guy minus r times t divided by N times F times Ln natural log of Q."}, {"title": "Nernst Equation Example .txt", "text": "Now, under a pressure or under a temperature of 25 degrees Celsius, we can rewrite this equation into this format."}, {"title": "Nernst Equation Example .txt", "text": "Now this guy we know, the Q we know."}, {"title": "Nernst Equation Example .txt", "text": "So what is the N?"}, {"title": "Nernst Equation Example .txt", "text": "Well, the N is the number of moles of electrons released by this equation."}, {"title": "Nernst Equation Example .txt", "text": "So notice that our zinc solid is the guy that gets oxidized."}, {"title": "Nernst Equation Example .txt", "text": "It releases two moles of electrons, right?"}, {"title": "Nernst Equation Example .txt", "text": "So that means this guy accepts two moles."}, {"title": "Nernst Equation Example .txt", "text": "It's reduced into zinc solid."}, {"title": "Nernst Equation Example .txt", "text": "So our N is two."}, {"title": "Nernst Equation Example .txt", "text": "So let's plug all our values into our formula and we get zero point 51 volts minus this number times log of 0.1\ndivided by our moles two."}, {"title": "Nernst Equation Example .txt", "text": "Now what we get is a number zero point 56 nine two."}, {"title": "Nernst Equation Example .txt", "text": "That's greater than our cell potential at equilibrium."}, {"title": "Nernst Equation Example .txt", "text": "What that means is that this condition of this concentrations of nonstandard conditions represent a situation in which the reaction is more product favored than at equilibrium."}, {"title": "Nernst Equation Example .txt", "text": "And that makes sense because this guy represents a condition at the beginning."}, {"title": "Nernst Equation Example .txt", "text": "So when we first add our Z and our nickel, what will happen?"}, {"title": "Nernst Equation Example .txt", "text": "Well, we won't have a lot of products form, we're going to have a lot of reactants."}, {"title": "Nernst Equation Example .txt", "text": "So according to Lash Palis principle where this reaction will be very product favored, very spontaneous in this direction and that's exactly what Q tells us."}, {"title": "Nernst Equation Example .txt", "text": "And that's exactly what this new E tells us."}, {"title": "Nernst Equation Example .txt", "text": "The fact that this guy is bigger than our equilibrium cell potential means that this reaction is more product favored than an equilibrium."}, {"title": "Cell voltage and Equilibrium constant .txt", "text": "So, in this lecture, we're going to look at a relationship between the equilibrium constant of a reduction reaction found in the electrochemical cell and that electrochemical cells cell voltage or its electromotive force."}, {"title": "Cell voltage and Equilibrium constant .txt", "text": "Now, before we look at the relationship, let's remember what equilibrium constant is."}, {"title": "Cell voltage and Equilibrium constant .txt", "text": "Suppose we have the following expression or reaction in which we have two reactants and two products."}, {"title": "Cell voltage and Equilibrium constant .txt", "text": "Now our A reactant is in the gas state, our B reactor is in the liquid state, our C product is in the Aqueous state and our D product is in the Aqueous state."}, {"title": "Cell voltage and Equilibrium constant .txt", "text": "So let's write the equilibrium constant expression for this reaction."}, {"title": "Cell voltage and Equilibrium constant .txt", "text": "And let's assume that equilibrium has been reached."}, {"title": "Cell voltage and Equilibrium constant .txt", "text": "So our equilibrium constant under standard conditions is equal to the concentration of product C times the concentration of product D divided by the concentration of product A."}, {"title": "Cell voltage and Equilibrium constant .txt", "text": "Now remember, whenever we're writing our equilibrium constant expressions, only aqueous molecules and gas molecules count in our equilibrium expression."}, {"title": "Cell voltage and Equilibrium constant .txt", "text": "We don't include liquid molecules or solid molecules."}, {"title": "Cell voltage and Equilibrium constant .txt", "text": "And that's exactly why we don't include the B molecule."}, {"title": "Cell voltage and Equilibrium constant .txt", "text": "Because it's in a liquid state."}, {"title": "Cell voltage and Equilibrium constant .txt", "text": "So we only get this expression no b is included."}, {"title": "Cell voltage and Equilibrium constant .txt", "text": "Now notice that this k is simply a ratio between the product concentration and the reactant concentration."}, {"title": "Cell voltage and Equilibrium constant .txt", "text": "So we say that if our K is greater than one, that means our reaction is favorable."}, {"title": "Cell voltage and Equilibrium constant .txt", "text": "If our K is less than one, our reaction is unfavorable."}, {"title": "Cell voltage and Equilibrium constant .txt", "text": "In other words, if it's greater than one, that means our equilibrium lies to the right."}, {"title": "Cell voltage and Equilibrium constant .txt", "text": "Because these guys completely react to form our products."}, {"title": "Cell voltage and Equilibrium constant .txt", "text": "In other words, if K is much larger than one, we have very little of our concentration of A and a lot of concentration of products, namely C and D.\nLikewise, if K is much less than one, that means we have lots of this guy left over at equilibrium and very little affirmation of our products."}, {"title": "Cell voltage and Equilibrium constant .txt", "text": "And that means equilibrium lies to the left, which also means we have very little of this guy and a lot of this guy."}, {"title": "Cell voltage and Equilibrium constant .txt", "text": "Now, let's look at B."}, {"title": "Cell voltage and Equilibrium constant .txt", "text": "So we just learned that the change in Gibbs free energy is equal to negative."}, {"title": "Cell voltage and Equilibrium constant .txt", "text": "N the number of moles of electrons times staradate constant times the cell voltage."}, {"title": "Cell voltage and Equilibrium constant .txt", "text": "Now, from before, we know that the change in Gates free Energy can Also Be Expressed as negative r times T.\nWell, R is the Gas constant at T's temperature in Kelvin times our Natural log of our K, our equilibrium constant expression on The Standard Conditions."}, {"title": "Cell voltage and Equilibrium constant .txt", "text": "Now, what we can do is set these guys equal."}, {"title": "Cell voltage and Equilibrium constant .txt", "text": "Why?"}, {"title": "Cell voltage and Equilibrium constant .txt", "text": "Well, because this and this are the same expressions, because they both equal the same thing."}, {"title": "Cell voltage and Equilibrium constant .txt", "text": "Namely change in Gibbs free energy."}, {"title": "Cell voltage and Equilibrium constant .txt", "text": "So let's set these guys equal."}, {"title": "Cell voltage and Equilibrium constant .txt", "text": "So we get negative MF times E equals negative RT, notch and log of K.\nSo we can basically rearrange this guy and solve for our cell voltage."}, {"title": "Cell voltage and Equilibrium constant .txt", "text": "And what we get is the negatives cancel and we bring the M and the F to this side."}, {"title": "Cell voltage and Equilibrium constant .txt", "text": "And we get our cell voltage equal to gas constant times temperature tail and divided by moles of electrons times paradise constant times natural log of our equilibrium constant."}, {"title": "Cell voltage and Equilibrium constant .txt", "text": "So this expression basically relates our cells voltage and the concentration of our reactants and products or the ratio of the concentration."}, {"title": "Cell voltage and Equilibrium constant .txt", "text": "Now, notice in this equation we have R is our constant and F is also constant."}, {"title": "Cell voltage and Equilibrium constant .txt", "text": "And if we assume constant temperature of, say, 25 degrees Celsius, we can simplify this expression into the following expression."}, {"title": "Cell voltage and Equilibrium constant .txt", "text": "So, let's rewrite this expression."}, {"title": "Cell voltage and Equilibrium constant .txt", "text": "Cell voltage E is equal to a constant times a constant outcase because T is 298 in Kelvin."}, {"title": "Cell voltage and Equilibrium constant .txt", "text": "Since we assume that temperature is constant and temperatures of 25 degrees Celsius, that's our assumption."}, {"title": "Cell voltage and Equilibrium constant .txt", "text": "That means in Kelvin, 25 plus a 73 is 298."}, {"title": "Cell voltage and Equilibrium constant .txt", "text": "So a constant times our temperature that's constant divided by another constant called Faraday's constant, we get something called 0.257 a number, right?"}, {"title": "Cell voltage and Equilibrium constant .txt", "text": "So this expression under these conditions gives us the following simplified expression."}, {"title": "Cell voltage and Equilibrium constant .txt", "text": "And this expression is nice because here we have three unknowns."}, {"title": "Cell voltage and Equilibrium constant .txt", "text": "This is our unknown, this is our unknown, and this is our unknown."}, {"title": "Cell voltage and Equilibrium constant .txt", "text": "So if we, for example, know our cell voltage and we know our number of moles, we can rearrange this equation and solve for K in the following way."}, {"title": "Cell voltage and Equilibrium constant .txt", "text": "Natural log of K is equal to N times cell voltage divided by zero point 25 seven."}, {"title": "Cell voltage and Equilibrium constant .txt", "text": "And suppose now we know our K and we know our end."}, {"title": "Cell voltage and Equilibrium constant .txt", "text": "That means we can use our equilibrium constant and our end to find our cell voltage."}, {"title": "Cell voltage and Equilibrium constant .txt", "text": "So these two equations become very useful."}, {"title": "Cell voltage and Equilibrium constant .txt", "text": "And these two equations build a relationship between the concentration of reactants and products and the cell's voltage."}, {"title": "Cell voltage and Equilibrium constant .txt", "text": "Now, notice one interesting thing."}, {"title": "Cell voltage and Equilibrium constant .txt", "text": "Whenever we take natural log of a number that's bigger than one, this expression becomes positive."}, {"title": "Cell voltage and Equilibrium constant .txt", "text": "And that means if this expression is positive, then this is positive."}, {"title": "Cell voltage and Equilibrium constant .txt", "text": "And recall that if our cell voltage is positive, that means we have a product favorite reaction."}, {"title": "Cell voltage and Equilibrium constant .txt", "text": "It's spontaneous."}, {"title": "Cell voltage and Equilibrium constant .txt", "text": "And that makes sense because earlier we said if we have a K greater than one, that means we have a favorable reaction."}, {"title": "Cell voltage and Equilibrium constant .txt", "text": "Our reaction favors this going this way."}, {"title": "Cell voltage and Equilibrium constant .txt", "text": "Likewise, if this K is less than one, if it's a zero nine, then this guy, our natural log of a number that's less than one becomes negative."}, {"title": "Cell voltage and Equilibrium constant .txt", "text": "So our e becomes negative."}, {"title": "Cell voltage and Equilibrium constant .txt", "text": "And that means if E is negative, our reaction is not product favorite, it's reactant favorite."}, {"title": "Cell voltage and Equilibrium constant .txt", "text": "And that means it's not favorable."}, {"title": "Cell voltage and Equilibrium constant .txt", "text": "And just like our K is less than one means that our reaction is unfavorable."}, {"title": "Cell voltage and Equilibrium constant .txt", "text": "The following thing I want to talk to you about is the following."}, {"title": "Cell voltage and Equilibrium constant .txt", "text": "I want to show you how we can convert the formula we just found to something simpler."}, {"title": "Cell voltage and Equilibrium constant .txt", "text": "Now, notice we're dealing with natural logs."}, {"title": "Cell voltage and Equilibrium constant .txt", "text": "That means if we were to convert this log to exponents, we would have to deal with bases of E.\nNow, bases Of E Aren't Very Easy To Calculate."}, {"title": "Cell voltage and Equilibrium constant .txt", "text": "You need a calculator to calculate basis of E. For example, you don't know what E to the one, E to the two."}, {"title": "Cell voltage and Equilibrium constant .txt", "text": "Each of the three."}, {"title": "Cell voltage and Equilibrium constant .txt", "text": "Well, maybe e to the one you do but e to the two e to the three to the four you don't really know what that is with that using calculator."}, {"title": "Cell voltage and Equilibrium constant .txt", "text": "But bases like Base Ten, that's easy to calculate, right?"}, {"title": "Cell voltage and Equilibrium constant .txt", "text": "Ten to the 110 to the 210 to the three."}, {"title": "Cell voltage and Equilibrium constant .txt", "text": "That's easy to calculate."}, {"title": "Cell voltage and Equilibrium constant .txt", "text": "You don't need a calculator."}, {"title": "Cell voltage and Equilibrium constant .txt", "text": "And therefore, our goal is to convert this natural log into base ten log?"}, {"title": "Cell voltage and Equilibrium constant .txt", "text": "And the way we do it is we have to remember from algebra what the base conversion formula is for logs."}, {"title": "Cell voltage and Equilibrium constant .txt", "text": "In other words, this is a formula that basically tells us we can convert any log of any base of any inside to the base of ten."}, {"title": "Cell voltage and Equilibrium constant .txt", "text": "So the way we do it is log of base X of Y is equal to log of base ten of y divided by log of base ten of X."}, {"title": "Cell voltage and Equilibrium constant .txt", "text": "Now, in our case, we have a natural log of some Y."}, {"title": "Cell voltage and Equilibrium constant .txt", "text": "And that's equivalent to saying log of base e of Y equals."}, {"title": "Cell voltage and Equilibrium constant .txt", "text": "That means we have to divide log of base ten of Y divided by log of base ten of E. So this is exactly what we follow in this process here."}, {"title": "Cell voltage and Equilibrium constant .txt", "text": "This step natural log of K is equal to log of base."}, {"title": "Cell voltage and Equilibrium constant .txt", "text": "E of K is equal to same exact process."}, {"title": "Cell voltage and Equilibrium constant .txt", "text": "This guy over this guy."}, {"title": "Cell voltage and Equilibrium constant .txt", "text": "Same thing that we did here is equal to now, this is something we know."}, {"title": "Cell voltage and Equilibrium constant .txt", "text": "We know what e is."}, {"title": "Cell voltage and Equilibrium constant .txt", "text": "E to the one is some number."}, {"title": "Cell voltage and Equilibrium constant .txt", "text": "So we basically plug this guy into the calculator and we find that it's zero point 43 four."}, {"title": "Cell voltage and Equilibrium constant .txt", "text": "So now we have a lot of base."}, {"title": "Cell voltage and Equilibrium constant .txt", "text": "Ten of K is equal to this whole guy."}, {"title": "Cell voltage and Equilibrium constant .txt", "text": "And this guy is over this guy, right?"}, {"title": "Cell voltage and Equilibrium constant .txt", "text": "So what we do next is we bring this guy over to this side."}, {"title": "Cell voltage and Equilibrium constant .txt", "text": "And that's what we do in step e. And we get late of base."}, {"title": "Cell voltage and Equilibrium constant .txt", "text": "Ten of K equals this guy is brought over to here."}, {"title": "Cell voltage and Equilibrium constant .txt", "text": "And what we get is zero point 43 four divided by zero point 25 seven times N times e. Now we plug this guy to the calculator, and we get 16.89\nmoles of electrons."}, {"title": "Cell voltage and Equilibrium constant .txt", "text": "Times or times moles electrons times cell voltage."}, {"title": "Cell voltage and Equilibrium constant .txt", "text": "Now, in textbooks you'll find this formula."}, {"title": "Cell voltage and Equilibrium constant .txt", "text": "But this guy and this guy are the same."}, {"title": "Cell voltage and Equilibrium constant .txt", "text": "Now, the way you go from this formula to this formula is you simply take this number and you reach the negative one power and you get this expression."}, {"title": "Cell voltage and Equilibrium constant .txt", "text": "They're the same exact expression."}, {"title": "Balancing Chemical Reactions and Limiting Reagents .txt", "text": "Now, in this lecture, we're going to look at reactions and their equations."}, {"title": "Balancing Chemical Reactions and Limiting Reagents .txt", "text": "Whenever a compound undergoes a reaction without changing its molecular formula, this type of reaction is known as a physical reaction."}, {"title": "Balancing Chemical Reactions and Limiting Reagents .txt", "text": "Now, examples include melting, freezing, evaporation and condensation."}, {"title": "Balancing Chemical Reactions and Limiting Reagents .txt", "text": "Now note that other examples exist."}, {"title": "Balancing Chemical Reactions and Limiting Reagents .txt", "text": "Now, let's look at evaporation of water."}, {"title": "Balancing Chemical Reactions and Limiting Reagents .txt", "text": "Whenever a water molecule in the liquid state gains enough kinetic energy, it escapes the bonds of the liquid molecules and becomes a gas molecule."}, {"title": "Balancing Chemical Reactions and Limiting Reagents .txt", "text": "And that means our compound goes from the liquid state to the gas state."}, {"title": "Balancing Chemical Reactions and Limiting Reagents .txt", "text": "But note that our molecular formula remains H 20."}, {"title": "Balancing Chemical Reactions and Limiting Reagents .txt", "text": "And that means evaporation is a physical reaction."}, {"title": "Balancing Chemical Reactions and Limiting Reagents .txt", "text": "Now, on the contrary, whenever a compound goes from one molecular formula to a different compound with a different molecular formula, this type of reaction is known as a chemical reaction."}, {"title": "Balancing Chemical Reactions and Limiting Reagents .txt", "text": "Now, examples include combustion of hydrocarbons in which a hydrocarbon burns in the presence of oxygen to produce carbon dioxide and water."}, {"title": "Balancing Chemical Reactions and Limiting Reagents .txt", "text": "Other examples include oxidation reduction reactions, combination and addition reactions."}, {"title": "Balancing Chemical Reactions and Limiting Reagents .txt", "text": "Now, let's look at the following chemical reaction in which the following hydrocarbon C, two S, H, six reacts in the presence of oxygen to form carbon dioxide and a water molecule."}, {"title": "Balancing Chemical Reactions and Limiting Reagents .txt", "text": "Now, remember what the conservation of energy and the conservation of mass tells us."}, {"title": "Balancing Chemical Reactions and Limiting Reagents .txt", "text": "Mass cannot be destroyed or created."}, {"title": "Balancing Chemical Reactions and Limiting Reagents .txt", "text": "It always exists."}, {"title": "Balancing Chemical Reactions and Limiting Reagents .txt", "text": "And that means whatever we put into our equation, we have to take out."}, {"title": "Balancing Chemical Reactions and Limiting Reagents .txt", "text": "In other words, the amount of atoms of each respective atom the carbon, the H and the O."}, {"title": "Balancing Chemical Reactions and Limiting Reagents .txt", "text": "Whatever we put in, we must get out."}, {"title": "Balancing Chemical Reactions and Limiting Reagents .txt", "text": "Now, notice in this equation we put in two C atoms and get one C. We put in six H atoms and only get two H atoms back."}, {"title": "Balancing Chemical Reactions and Limiting Reagents .txt", "text": "And somehow we put in only two O atoms and we get three O atoms back."}, {"title": "Balancing Chemical Reactions and Limiting Reagents .txt", "text": "This type of an equation where our numbers are unbalanced, our coefficients and atoms are imbalanced, is known as an unbalanced equation."}, {"title": "Balancing Chemical Reactions and Limiting Reagents .txt", "text": "To balance this equation, we basically have to multiply each atom by some number so that the number on this side of each atom equals the number on this side."}, {"title": "Balancing Chemical Reactions and Limiting Reagents .txt", "text": "So let's balance this out."}, {"title": "Balancing Chemical Reactions and Limiting Reagents .txt", "text": "Now, let's begin with carbon."}, {"title": "Balancing Chemical Reactions and Limiting Reagents .txt", "text": "Now, on this side, we have two carbons, while on this side, we only have one carbon."}, {"title": "Balancing Chemical Reactions and Limiting Reagents .txt", "text": "To balance this out, we multiply this side, this CO2, by two."}, {"title": "Balancing Chemical Reactions and Limiting Reagents .txt", "text": "If we multiply this by two, we get two carbons on this side and two carbons on this side."}, {"title": "Balancing Chemical Reactions and Limiting Reagents .txt", "text": "So now, whatever amount of carbons we put in, namely two, we get two back."}, {"title": "Balancing Chemical Reactions and Limiting Reagents .txt", "text": "So that makes sense."}, {"title": "Balancing Chemical Reactions and Limiting Reagents .txt", "text": "Next, let's balance out the H atoms."}, {"title": "Balancing Chemical Reactions and Limiting Reagents .txt", "text": "Now, we put in six H atoms and only get two back."}, {"title": "Balancing Chemical Reactions and Limiting Reagents .txt", "text": "So let's multiply this water molecule by a coefficient of three."}, {"title": "Balancing Chemical Reactions and Limiting Reagents .txt", "text": "So if we multiply it by three, we get six H atoms and six H atoms."}, {"title": "Balancing Chemical Reactions and Limiting Reagents .txt", "text": "So we're putting in two C atoms and six H atoms and we're getting back two C atoms and six H atoms."}, {"title": "Balancing Chemical Reactions and Limiting Reagents .txt", "text": "Finally, let's balance the oxygen out."}, {"title": "Balancing Chemical Reactions and Limiting Reagents .txt", "text": "So notice we have two times two oxygens."}, {"title": "Balancing Chemical Reactions and Limiting Reagents .txt", "text": "So four oxygen here, and three times one oxygen, three oxygens here."}, {"title": "Balancing Chemical Reactions and Limiting Reagents .txt", "text": "So we have a total of seven oxygens here."}, {"title": "Balancing Chemical Reactions and Limiting Reagents .txt", "text": "That means we have to multiply this guy by seven over two, because seven over two times two, the twos cancel and we are left with seven oxygen molecules here."}, {"title": "Balancing Chemical Reactions and Limiting Reagents .txt", "text": "So, in other words, we put in two carbons, six HS, and seven OS, and we get back two carbons, six H's, and three times one, two times four, seven O's."}, {"title": "Balancing Chemical Reactions and Limiting Reagents .txt", "text": "So this type of reaction is called a balanced equation."}, {"title": "Balancing Chemical Reactions and Limiting Reagents .txt", "text": "Now, notice that what these coefficients represent is moles or molecules or atoms."}, {"title": "Balancing Chemical Reactions and Limiting Reagents .txt", "text": "But what they can't never represent is mass."}, {"title": "Balancing Chemical Reactions and Limiting Reagents .txt", "text": "So these numbers, these coefficients, in this case, one, one, one, in this case, one seven over two, two and three will never represent mass."}, {"title": "Balancing Chemical Reactions and Limiting Reagents .txt", "text": "So never kilograms, never grams, never pounds, never any type of mass."}, {"title": "Balancing Chemical Reactions and Limiting Reagents .txt", "text": "Only moles atoms or molecules."}, {"title": "Balancing Chemical Reactions and Limiting Reagents .txt", "text": "In other words, 1 mol of this hydrocarbon reacts with seven over two moles of diatomic oxygen to produce two moles of carbon dioxide and three moles of water."}, {"title": "Balancing Chemical Reactions and Limiting Reagents .txt", "text": "We can never say 1 gram of this car react with seven over 2 grams."}, {"title": "Balancing Chemical Reactions and Limiting Reagents .txt", "text": "That makes no sense."}, {"title": "Balancing Chemical Reactions and Limiting Reagents .txt", "text": "These coefficients represent moles, molecules or atom, never any mass."}, {"title": "Balancing Chemical Reactions and Limiting Reagents .txt", "text": "So whenever a reaction is set to run to completion, what that basically means is that one of the reactants is completely used up."}, {"title": "Balancing Chemical Reactions and Limiting Reagents .txt", "text": "It's completely depleted."}, {"title": "Balancing Chemical Reactions and Limiting Reagents .txt", "text": "Note, however, most reactions do not run to completion."}, {"title": "Balancing Chemical Reactions and Limiting Reagents .txt", "text": "And that's because before one of the reactants is used up, equilibrium is established."}, {"title": "Balancing Chemical Reactions and Limiting Reagents .txt", "text": "Now, suppose the following reaction x plus Y react to form our product XY."}, {"title": "Balancing Chemical Reactions and Limiting Reagents .txt", "text": "And suppose this reaction achieves equilibrium before one of the reactants is used up."}, {"title": "Balancing Chemical Reactions and Limiting Reagents .txt", "text": "What that means is that the forward reaction rate is equal to the reverse reaction rate."}, {"title": "Balancing Chemical Reactions and Limiting Reagents .txt", "text": "So the rate at which our reactants react to produce our product is the same as the rate at which the product associates into our reactants."}, {"title": "Balancing Chemical Reactions and Limiting Reagents .txt", "text": "In other words, the concentration of these guys and this guy remains the same even though the reactions are occurring."}, {"title": "Balancing Chemical Reactions and Limiting Reagents .txt", "text": "And that's because they're occurring at the same rates."}, {"title": "Balancing Chemical Reactions and Limiting Reagents .txt", "text": "Now, suppose we have the following combustion reaction in which methane combusts in the presence of oxygen to produce carbon dioxide and water."}, {"title": "Balancing Chemical Reactions and Limiting Reagents .txt", "text": "Suppose this reaction is allowed to go to completion."}, {"title": "Balancing Chemical Reactions and Limiting Reagents .txt", "text": "Now, what happens if two moles of methane of this guy react with six moles of water?"}, {"title": "Balancing Chemical Reactions and Limiting Reagents .txt", "text": "So what happens?"}, {"title": "Balancing Chemical Reactions and Limiting Reagents .txt", "text": "Well, let's see."}, {"title": "Balancing Chemical Reactions and Limiting Reagents .txt", "text": "Let's first notice that the ratio of the number of moles of methane, the number of moles of oxygen is one to two."}, {"title": "Balancing Chemical Reactions and Limiting Reagents .txt", "text": "So that means whenever 1 mol reacts with two moles of this guy, they produce carbon dioxide, 1 mol and two moles of water."}, {"title": "Balancing Chemical Reactions and Limiting Reagents .txt", "text": "So now we have two moles of methane reacting with oxygen."}, {"title": "Balancing Chemical Reactions and Limiting Reagents .txt", "text": "That means, since not one, but two moles of methane are reacting, that means not two, but four moles of oxygen will react to produce our products."}, {"title": "Balancing Chemical Reactions and Limiting Reagents .txt", "text": "That's because two times two is four."}, {"title": "Balancing Chemical Reactions and Limiting Reagents .txt", "text": "That means we're going to produce two moles of carbon dioxide and four moles of oxygen."}, {"title": "Balancing Chemical Reactions and Limiting Reagents .txt", "text": "Now, it's exactly what I said here."}, {"title": "Balancing Chemical Reactions and Limiting Reagents .txt", "text": "Once our reaction runs to completion, two moles of methane and four moles of oxygen are used up to produce two moles of carbon dioxide and four moles of H 20."}, {"title": "Balancing Chemical Reactions and Limiting Reagents .txt", "text": "But notice we begin with six moles of oxygen."}, {"title": "Balancing Chemical Reactions and Limiting Reagents .txt", "text": "That means if only four moles of oxygen were used up, we have two moles of oxygen left over."}, {"title": "Balancing Chemical Reactions and Limiting Reagents .txt", "text": "And that means one of the reactants is completely used up."}, {"title": "Balancing Chemical Reactions and Limiting Reagents .txt", "text": "It's depleted while the other reactants is still left."}, {"title": "Balancing Chemical Reactions and Limiting Reagents .txt", "text": "So some of this guy is left over."}, {"title": "Balancing Chemical Reactions and Limiting Reagents .txt", "text": "That means this guy is our limiting reagent."}, {"title": "Balancing Chemical Reactions and Limiting Reagents .txt", "text": "A limiting reagent is simply a reactant that's completely used up."}, {"title": "Balancing Chemical Reactions and Limiting Reagents .txt", "text": "Now, if both of these guys were used up, that means both of these guys or the limiting reagents."}, {"title": "Electrochemical Gradient of Cell Membrane.txt", "text": "In this lecture, my goal will be to explain to you a biological process using chemistry."}, {"title": "Electrochemical Gradient of Cell Membrane.txt", "text": "I will show you that the movement of ions across the cell membrane in a neuron cell is identical to the movement of ions in a concentration cell."}, {"title": "Electrochemical Gradient of Cell Membrane.txt", "text": "And in fact, a neuron cell is a more complex version of a concentration cell."}, {"title": "Electrochemical Gradient of Cell Membrane.txt", "text": "So let's begin."}, {"title": "Electrochemical Gradient of Cell Membrane.txt", "text": "So let's this is our cell membrane in a neuron cell."}, {"title": "Electrochemical Gradient of Cell Membrane.txt", "text": "Here's our outside, the cell and the inside of the cell."}, {"title": "Electrochemical Gradient of Cell Membrane.txt", "text": "Now, assuming our cell reaches a rusting electrical potential, we're going to have many more of these sodium ions on the outside than on the inside."}, {"title": "Electrochemical Gradient of Cell Membrane.txt", "text": "Now, what will entropy tell us about this situation?"}, {"title": "Electrochemical Gradient of Cell Membrane.txt", "text": "Well, entropy will tell us that our system is not even and we will want to move towards a more even system."}, {"title": "Electrochemical Gradient of Cell Membrane.txt", "text": "In other words, some of these guys will want to move inside the cell so that we have the same number of ions on the inside as outside."}, {"title": "Electrochemical Gradient of Cell Membrane.txt", "text": "So at this point, we say there's a high concentration gradient or high chemical gradient on the outside."}, {"title": "Electrochemical Gradient of Cell Membrane.txt", "text": "And the concentration gradient simply comes from the number of molecules."}, {"title": "Electrochemical Gradient of Cell Membrane.txt", "text": "The more molecules they are, the higher the concentration gradient."}, {"title": "Electrochemical Gradient of Cell Membrane.txt", "text": "And things tend to move from a high concentration gradient to a low concentration gradient."}, {"title": "Electrochemical Gradient of Cell Membrane.txt", "text": "So ions will want to move from the outside to the inside due to a chemical or concentration gradient."}, {"title": "Electrochemical Gradient of Cell Membrane.txt", "text": "Now notice what happens as our positively charged ions begin to move to the inside."}, {"title": "Electrochemical Gradient of Cell Membrane.txt", "text": "Well, as this one moves, then this one moves, and the third one moves, and the fourth one moves."}, {"title": "Electrochemical Gradient of Cell Membrane.txt", "text": "What happens?"}, {"title": "Electrochemical Gradient of Cell Membrane.txt", "text": "Well, there's a build up of positive charge on this side."}, {"title": "Electrochemical Gradient of Cell Membrane.txt", "text": "As these guys go across the membrane, there's a build up of positive charge."}, {"title": "Electrochemical Gradient of Cell Membrane.txt", "text": "And this slows down the movement because positive charge and positive charge repel."}, {"title": "Electrochemical Gradient of Cell Membrane.txt", "text": "And so eventually, these guys will stop moving this way."}, {"title": "Electrochemical Gradient of Cell Membrane.txt", "text": "And that means now we can talk about another gradient called the electrical gradient."}, {"title": "Electrochemical Gradient of Cell Membrane.txt", "text": "Now, the electrical gradient is due to charge and not number."}, {"title": "Electrochemical Gradient of Cell Membrane.txt", "text": "So the more charge there is here, the more our electrical gradient will play a role in dictating in which direction our molecule moves."}, {"title": "Electrochemical Gradient of Cell Membrane.txt", "text": "And in fact, when the chemical gradient or the concentration gradient equals the electrical gradient, the rates that these molecules are moving inside is going to equal to the rates at which they're moving to the outside."}, {"title": "Electrochemical Gradient of Cell Membrane.txt", "text": "And that's exactly what a rusting potential is."}, {"title": "Electrochemical Gradient of Cell Membrane.txt", "text": "It's in the equilibrium state."}, {"title": "Electrochemical Gradient of Cell Membrane.txt", "text": "So now let's look at our electrochemical cells or a concentration cell."}, {"title": "Electrochemical Gradient of Cell Membrane.txt", "text": "In the first half cell."}, {"title": "Electrochemical Gradient of Cell Membrane.txt", "text": "This is our anode oxidation takes place."}, {"title": "Electrochemical Gradient of Cell Membrane.txt", "text": "And now cathode reduction takes place."}, {"title": "Electrochemical Gradient of Cell Membrane.txt", "text": "So notice that these guys so we have the two in an electrodes."}, {"title": "Electrochemical Gradient of Cell Membrane.txt", "text": "We have the conductor and the sole bridge."}, {"title": "Electrochemical Gradient of Cell Membrane.txt", "text": "These guys can be thought of as being the membrane."}, {"title": "Electrochemical Gradient of Cell Membrane.txt", "text": "Okay?"}, {"title": "Electrochemical Gradient of Cell Membrane.txt", "text": "Now what happens in this cell?"}, {"title": "Electrochemical Gradient of Cell Membrane.txt", "text": "Well, if in this cell oxidation takes place, then our sodium side molecules oh, by the way, these guys are made from sodium solid."}, {"title": "Electrochemical Gradient of Cell Membrane.txt", "text": "So our sodium solid molecules are oxidized, releasing our NA molecules into our solution and releasing electrons into this conductor."}, {"title": "Electrochemical Gradient of Cell Membrane.txt", "text": "These electrons then transfer all the way to this electrode, react with a positively charged ion, which is taken off from the solution into our electrode."}, {"title": "Electrochemical Gradient of Cell Membrane.txt", "text": "They react to produce sodium solid."}, {"title": "Electrochemical Gradient of Cell Membrane.txt", "text": "So really, as our reaction progresses, our concentration of sodium ions increases in beaker one and decreases in beaker two."}, {"title": "Electrochemical Gradient of Cell Membrane.txt", "text": "So, in a way, we can think of our sodium ions traveling from this speaker beaker two to beaker one, from the cathode to the anode."}, {"title": "Electrochemical Gradient of Cell Membrane.txt", "text": "And that is exactly why we consider this speaker one to be the inside and this speaker two to be the outside, right?"}, {"title": "Electrochemical Gradient of Cell Membrane.txt", "text": "Because initially on the inside, we have less sodium ions than on the outside."}, {"title": "Electrochemical Gradient of Cell Membrane.txt", "text": "Here, we have more."}, {"title": "Electrochemical Gradient of Cell Membrane.txt", "text": "And when we have our right potential, this is the amount of sodium ions on the inside, and this is the amount of sodium ions on the outside."}, {"title": "Electrochemical Gradient of Cell Membrane.txt", "text": "Now notice what happens."}, {"title": "Electrochemical Gradient of Cell Membrane.txt", "text": "Our sodium ions tend to move from the outside to the inside, and the same thing is dictated by this concentration system."}, {"title": "Electrochemical Gradient of Cell Membrane.txt", "text": "Also, electrons tend to move from the abode to the cathode."}, {"title": "Electrochemical Gradient of Cell Membrane.txt", "text": "Likewise, electrons move from a high electrical gradient to a low electrical gradient, right?"}, {"title": "Electrochemical Gradient of Cell Membrane.txt", "text": "What happens as the ions move from this guy to this guy?"}, {"title": "Electrochemical Gradient of Cell Membrane.txt", "text": "Well, there is a build up of electrical gradient on this side."}, {"title": "Electrochemical Gradient of Cell Membrane.txt", "text": "It increases, and then electrons begin to transfer from this side to this side, right?"}, {"title": "Electrochemical Gradient of Cell Membrane.txt", "text": "And that's exactly what happens in this system, too."}, {"title": "Electrochemical Gradient of Cell Membrane.txt", "text": "The solar lines move this way."}, {"title": "Electrochemical Gradient of Cell Membrane.txt", "text": "The solar move this way, and electrons move the other way, and electrons move the other way."}, {"title": "Electrochemical Gradient of Cell Membrane.txt", "text": "So a neuron cell is simply a complex version of a concentration cell."}, {"title": "Electrochemical Gradient of Cell Membrane.txt", "text": "And the ions and electrons move in the same way in a cell membrane of a neuron cell as they do in a concentration cell."}, {"title": "Electrochemical Gradient of Cell Membrane.txt", "text": "And now we can use this concentration cell set up with the oxidation reduction reactions to calculate our cell voltage or rustic potential due to these sodium ions."}, {"title": "Electrochemical Gradient of Cell Membrane.txt", "text": "And let's do exactly that."}, {"title": "Electrochemical Gradient of Cell Membrane.txt", "text": "So here's our oxidation reaction and our reduction reaction."}, {"title": "Electrochemical Gradient of Cell Membrane.txt", "text": "We add these guys up to find a net reaction."}, {"title": "Electrochemical Gradient of Cell Membrane.txt", "text": "Now, these guys cancel out."}, {"title": "Electrochemical Gradient of Cell Membrane.txt", "text": "The electrons cancel out, and we are left with the sodium ions in the cathode and the sodium ions in the anode."}, {"title": "Electrochemical Gradient of Cell Membrane.txt", "text": "And so according to our net reduction, there's a transfer of these guys from the cathode to the anode."}, {"title": "Electrochemical Gradient of Cell Membrane.txt", "text": "And that's exactly what we see in this system and in this system."}, {"title": "Electrochemical Gradient of Cell Membrane.txt", "text": "So now what we do is we simply realize that our Q for this system is the concentration of this guy over the concentration of this guy."}, {"title": "Electrochemical Gradient of Cell Membrane.txt", "text": "So let's go back to our nurse equation."}, {"title": "Electrochemical Gradient of Cell Membrane.txt", "text": "Notice that our e for standard conditions cancels out because we have the same type of equation, and so they have the same magnitude of different signs."}, {"title": "Electrochemical Gradient of Cell Membrane.txt", "text": "So when you look the value up on a table you add them up and they cancel out."}, {"title": "Electrochemical Gradient of Cell Membrane.txt", "text": "That's why that e goes away."}, {"title": "Electrochemical Gradient of Cell Membrane.txt", "text": "And now we have E equals negative RTln of Q over N F. Now, F is a constant."}, {"title": "Electrochemical Gradient of Cell Membrane.txt", "text": "R is a constant."}, {"title": "Electrochemical Gradient of Cell Membrane.txt", "text": "Since this is a neuron cell, it's by temperature."}, {"title": "Electrochemical Gradient of Cell Membrane.txt", "text": "So 37 degrees Celsius."}, {"title": "Electrochemical Gradient of Cell Membrane.txt", "text": "37 plus 273 is 310."}, {"title": "Electrochemical Gradient of Cell Membrane.txt", "text": "Now, let's see."}, {"title": "Electrochemical Gradient of Cell Membrane.txt", "text": "R is a constant."}, {"title": "Electrochemical Gradient of Cell Membrane.txt", "text": "F is a constant."}, {"title": "Electrochemical Gradient of Cell Membrane.txt", "text": "N is the number of electrons."}, {"title": "Electrochemical Gradient of Cell Membrane.txt", "text": "In our case, we have 1 mol of electron on this side and on this side."}, {"title": "Electrochemical Gradient of Cell Membrane.txt", "text": "So n is one."}, {"title": "Electrochemical Gradient of Cell Membrane.txt", "text": "Now, Q, we said, is the concentration in the anode over the concentration in the cathode?"}, {"title": "Electrochemical Gradient of Cell Membrane.txt", "text": "So 0.018 molar over zero point 150 molar."}, {"title": "Electrochemical Gradient of Cell Membrane.txt", "text": "The amp cancel and we get this guy here."}, {"title": "Electrochemical Gradient of Cell Membrane.txt", "text": "Now we plug this into the calculator."}, {"title": "Electrochemical Gradient of Cell Membrane.txt", "text": "We get a negative number and there's a negative on the outside."}, {"title": "Electrochemical Gradient of Cell Membrane.txt", "text": "So the negatives cancel."}, {"title": "Electrochemical Gradient of Cell Membrane.txt", "text": "And this is our final answer."}, {"title": "Electrochemical Gradient of Cell Membrane.txt", "text": "Now, once again, I want to really talk about what this guy means, because this guy is important."}, {"title": "Electrochemical Gradient of Cell Membrane.txt", "text": "This is what is achieved at Equilibrium, right?"}, {"title": "Electrochemical Gradient of Cell Membrane.txt", "text": "This means that when equilibrium is achieved, the chemical gradient or the concentration gradient equals the electrical gradient."}, {"title": "Electrochemical Gradient of Cell Membrane.txt", "text": "So their rates are equal."}, {"title": "Electrochemical Gradient of Cell Membrane.txt", "text": "And this is exactly what it is."}, {"title": "Electrochemical Gradient of Cell Membrane.txt", "text": "So our concentration gradient is zero point 57 volts."}, {"title": "Electrochemical Gradient of Cell Membrane.txt", "text": "But our electrical gradient is negative."}, {"title": "Electrochemical Gradient of Cell Membrane.txt", "text": "Zero point 57."}, {"title": "Electrochemical Gradient of Cell Membrane.txt", "text": "Remember?"}, {"title": "Electrochemical Gradient of Cell Membrane.txt", "text": "Because they're reversed."}, {"title": "Electrochemical Gradient of Cell Membrane.txt", "text": "When the concentration gradient pushes it one way, the electrical gradient, these electrons push it the other way."}, {"title": "Electrochemical Gradient of Cell Membrane.txt", "text": "So they have the same magnitude to equilibrium, but they have different signs."}, {"title": "Electrochemical Gradient of Cell Membrane.txt", "text": "And this is exactly what it means."}, {"title": "Drawing Lewis Structures Example #2.txt", "text": "Now, in this lecture, I'd like to continue our discussion on Lewis dot structures."}, {"title": "Drawing Lewis Structures Example #2.txt", "text": "Now, before, we only spoke about neutral species or neutral molecules."}, {"title": "Drawing Lewis Structures Example #2.txt", "text": "Now we're going to draw Lewis dot structures for charged species or charged molecules."}, {"title": "Drawing Lewis Structures Example #2.txt", "text": "So let's begin with A."}, {"title": "Drawing Lewis Structures Example #2.txt", "text": "In a, we have an oh or a hydroxide molecule that has a negative one charge on the oxygen."}, {"title": "Drawing Lewis Structures Example #2.txt", "text": "Now, that negative one charge on the oxygen simply means that oxygen has one more electron than it does in its neutral state."}, {"title": "Drawing Lewis Structures Example #2.txt", "text": "In other words, in its neutral state, oxygen has eight electrons and eight protons."}, {"title": "Drawing Lewis Structures Example #2.txt", "text": "Now, a charge negative one oxygen molecule has eight protons, but now it has nine electrons."}, {"title": "Drawing Lewis Structures Example #2.txt", "text": "So let's draw our electron configuration for oxygen."}, {"title": "Drawing Lewis Structures Example #2.txt", "text": "So two electrons go into the one s, two electrons go into the two s, and five electrons go into the two p. Now, H stays the same because H is neutral."}, {"title": "Drawing Lewis Structures Example #2.txt", "text": "And so we place one electron into our one s orbital."}, {"title": "Drawing Lewis Structures Example #2.txt", "text": "So let's begin by first counting the total amount of balanced electrons that we have."}, {"title": "Drawing Lewis Structures Example #2.txt", "text": "Remember, balanced electrons are those electrons found in the outermost energy shell."}, {"title": "Drawing Lewis Structures Example #2.txt", "text": "For oxygen, that happens to be the N equals two shell."}, {"title": "Drawing Lewis Structures Example #2.txt", "text": "So two plus five equals seven."}, {"title": "Drawing Lewis Structures Example #2.txt", "text": "So seven balance electrons for o, and we have one electron in the balanced electron of one s for H. So we have all together eight electrons, eight balanced electrons that we will have to place around our atoms."}, {"title": "Drawing Lewis Structures Example #2.txt", "text": "So let's begin by placing our oxygen and H adjacent to one another."}, {"title": "Drawing Lewis Structures Example #2.txt", "text": "So we have eight electrons."}, {"title": "Drawing Lewis Structures Example #2.txt", "text": "Let's begin by drawing a sigma oracovalent bond between oxygen and nitrogen."}, {"title": "Drawing Lewis Structures Example #2.txt", "text": "So once we draw this line, that basically means that one electron is being donated by H and one electron is being donated by o."}, {"title": "Drawing Lewis Structures Example #2.txt", "text": "Now, this means that all the orbitals, meaning this one s orbital, is completely filled for H. Because before, when H is by itself, it has one electron in its one s shell."}, {"title": "Drawing Lewis Structures Example #2.txt", "text": "But now this electron is being shared."}, {"title": "Drawing Lewis Structures Example #2.txt", "text": "So we have two electrons in the one s shell."}, {"title": "Drawing Lewis Structures Example #2.txt", "text": "And that means all electrons or all the orbitals of the age are completely filled."}, {"title": "Drawing Lewis Structures Example #2.txt", "text": "So we can't place any more electrons around our age."}, {"title": "Drawing Lewis Structures Example #2.txt", "text": "How about oxygen?"}, {"title": "Drawing Lewis Structures Example #2.txt", "text": "Well, oxygen has more orbitals, right?"}, {"title": "Drawing Lewis Structures Example #2.txt", "text": "When this orbital is still it has three more orbitals."}, {"title": "Drawing Lewis Structures Example #2.txt", "text": "So that means we can place the remaining six valve electrons into or around our oxygen."}, {"title": "Drawing Lewis Structures Example #2.txt", "text": "So we place a pair here."}, {"title": "Drawing Lewis Structures Example #2.txt", "text": "A place we place a pair here, and we place a pair here."}, {"title": "Drawing Lewis Structures Example #2.txt", "text": "Now, notice in its mutual state, oxygen has six electrons."}, {"title": "Drawing Lewis Structures Example #2.txt", "text": "But because we have one plus one plus one plus one plus one plus one plus one, this gives us six or seven electrons."}, {"title": "Drawing Lewis Structures Example #2.txt", "text": "That means we're going to have a negative one charge on the oxygen."}, {"title": "Drawing Lewis Structures Example #2.txt", "text": "So this concludes our Lewis dot structure."}, {"title": "Drawing Lewis Structures Example #2.txt", "text": "Just to make sure, let's make sure we have the right amount of electrons."}, {"title": "Drawing Lewis Structures Example #2.txt", "text": "So our electron counts, we have two electrons in the bonding or covalent bond, and six non bonding electrons surrounding our oxygen."}, {"title": "Drawing Lewis Structures Example #2.txt", "text": "So two plus six is eight."}, {"title": "Drawing Lewis Structures Example #2.txt", "text": "We begin with eight balance electrons."}, {"title": "Drawing Lewis Structures Example #2.txt", "text": "We end with eight balance electrons."}, {"title": "Drawing Lewis Structures Example #2.txt", "text": "Oxygen has a negative one charge."}, {"title": "Drawing Lewis Structures Example #2.txt", "text": "So this concludes part a."}, {"title": "Drawing Lewis Structures Example #2.txt", "text": "Let's move to part b."}, {"title": "Drawing Lewis Structures Example #2.txt", "text": "In part B, we have this BH four molecule."}, {"title": "Drawing Lewis Structures Example #2.txt", "text": "Now b is boron."}, {"title": "Drawing Lewis Structures Example #2.txt", "text": "Normally, boron has five protons and five electrons in its neutral state."}, {"title": "Drawing Lewis Structures Example #2.txt", "text": "But because this has a negative one charge, it has one more electron."}, {"title": "Drawing Lewis Structures Example #2.txt", "text": "So that means it has a total of six electrons and five protons."}, {"title": "Drawing Lewis Structures Example #2.txt", "text": "So two going to the one s, two going to the two s, and two going to the two p. H still has that one electron in the one s because it's neutral."}, {"title": "Drawing Lewis Structures Example #2.txt", "text": "Now, notice, however, now we have four h atoms."}, {"title": "Drawing Lewis Structures Example #2.txt", "text": "And that means when we're counting our balanced electrons, we have not one electron from h, but four electrons from h. So four times one."}, {"title": "Drawing Lewis Structures Example #2.txt", "text": "So we have four electrons coming from h, and two plus two four electrons coming from our boron."}, {"title": "Drawing Lewis Structures Example #2.txt", "text": "So altogether, we have eight balanced electrons."}, {"title": "Drawing Lewis Structures Example #2.txt", "text": "So once again, we place our b in the middle, our central atom, and we place our h atoms around our b atom."}, {"title": "Drawing Lewis Structures Example #2.txt", "text": "So we begin by first creating sigma or covalent bonds."}, {"title": "Drawing Lewis Structures Example #2.txt", "text": "So we connect our b's and HS, and now we have four covalent bonds."}, {"title": "Drawing Lewis Structures Example #2.txt", "text": "So let's count how many electrons we have."}, {"title": "Drawing Lewis Structures Example #2.txt", "text": "So we begin with eight."}, {"title": "Drawing Lewis Structures Example #2.txt", "text": "And now we have 1234-5678."}, {"title": "Drawing Lewis Structures Example #2.txt", "text": "So we have completely used up all our balance electrons, and that means that this is our lewis structure."}, {"title": "Drawing Lewis Structures Example #2.txt", "text": "Now, normally, boron could form three bonds, so it has three electrons."}, {"title": "Drawing Lewis Structures Example #2.txt", "text": "But in this case, it has 12341 more electron than in its neutral state."}, {"title": "Drawing Lewis Structures Example #2.txt", "text": "And that means that it has a negative one charge."}, {"title": "Drawing Lewis Structures Example #2.txt", "text": "So let's do our electron count."}, {"title": "Drawing Lewis Structures Example #2.txt", "text": "We have eight bonding electrons, right?"}, {"title": "Drawing Lewis Structures Example #2.txt", "text": "2468 and zero non bonding."}, {"title": "Drawing Lewis Structures Example #2.txt", "text": "So we have a net of eight electrons."}, {"title": "Drawing Lewis Structures Example #2.txt", "text": "And that concludes our picture for b."}, {"title": "Drawing Lewis Structures Example #2.txt", "text": "Let's jump to part C. In part C, we have this ammonium atom, or NH, four positive."}, {"title": "Drawing Lewis Structures Example #2.txt", "text": "That means nitrogen has one less electron than it does in its neutral state."}, {"title": "Drawing Lewis Structures Example #2.txt", "text": "So let's draw our electron configuration."}, {"title": "Drawing Lewis Structures Example #2.txt", "text": "For n.\nOne or two electrons go into the two s, two electrons go to the two or two electrons going to the one s, two electrons go to the two s, and two electrons go into the two p now, normally, in a neutral atom, we would have three electrons going to the two P. But because it has a plus one, that means it has one more proton in an electron."}, {"title": "Drawing Lewis Structures Example #2.txt", "text": "So it has only two electrons in the two p.\nH, once again, is neutral, so it has one electron in the one s orbital."}, {"title": "Drawing Lewis Structures Example #2.txt", "text": "Once again, we count our balanced electrons."}, {"title": "Drawing Lewis Structures Example #2.txt", "text": "We have two and two."}, {"title": "Drawing Lewis Structures Example #2.txt", "text": "So four electrons coming from n, and one times four."}, {"title": "Drawing Lewis Structures Example #2.txt", "text": "So eight balanced electrons altogether."}, {"title": "Drawing Lewis Structures Example #2.txt", "text": "So once again, the same story."}, {"title": "Drawing Lewis Structures Example #2.txt", "text": "We draw out our N, that central atom in the middle."}, {"title": "Drawing Lewis Structures Example #2.txt", "text": "We draw our four HS around and we connect our HS and NS."}, {"title": "Drawing Lewis Structures Example #2.txt", "text": "So notice we have two, four, six and eight."}, {"title": "Drawing Lewis Structures Example #2.txt", "text": "So we have a total of eight balanced electrons."}, {"title": "Drawing Lewis Structures Example #2.txt", "text": "So we have used up our balanced electrons."}, {"title": "Drawing Lewis Structures Example #2.txt", "text": "And this must be the electron configuration for NH four."}, {"title": "Drawing Lewis Structures Example #2.txt", "text": "Notice that once again, n is used to having five electrons."}, {"title": "Drawing Lewis Structures Example #2.txt", "text": "Here."}, {"title": "Drawing Lewis Structures Example #2.txt", "text": "It has four electrons."}, {"title": "Drawing Lewis Structures Example #2.txt", "text": "1234"}, {"title": "Drawing Lewis Structures Example #2.txt", "text": "So it has a plus one charge on the N, and these HS are neutral."}, {"title": "Drawing Lewis Structures Example #2.txt", "text": "So a net charge of plus one."}, {"title": "Drawing Lewis Structures Example #2.txt", "text": "Once again our electron count."}, {"title": "Drawing Lewis Structures Example #2.txt", "text": "Eight electrons coming from the bonding orbitals."}, {"title": "Drawing Lewis Structures Example #2.txt", "text": "Or the bonding electrons."}, {"title": "Drawing Lewis Structures Example #2.txt", "text": "And we have zero non bonding electrons, just like we had in this picture here."}, {"title": "Drawing Lewis Structures Example #2.txt", "text": "So let's go to the last one."}, {"title": "Drawing Lewis Structures Example #2.txt", "text": "Part D.\nIn Part D, we have NH Two with a minus one."}, {"title": "Drawing Lewis Structures Example #2.txt", "text": "So right here we had a plus one and here we have a minus one on the end."}, {"title": "Drawing Lewis Structures Example #2.txt", "text": "That means it will have one more electron than a dot in its neutral state."}, {"title": "Drawing Lewis Structures Example #2.txt", "text": "So instead of having three electrons in its two p it's going to have four electrons in its two p orbital."}, {"title": "Drawing Lewis Structures Example #2.txt", "text": "So two going to the one S, two going to the two S, and four going to the two P. H is once again neutral."}, {"title": "Drawing Lewis Structures Example #2.txt", "text": "It has one electron in the one s. So we have two h atoms."}, {"title": "Drawing Lewis Structures Example #2.txt", "text": "So two times one, we have two electrons balance electrons coming from h and two plus four six electrons coming from n.\nSo altogether, once again we have eight balance electrons."}, {"title": "Drawing Lewis Structures Example #2.txt", "text": "So once again we begin our drawing by writing or drawing n in the middle of the central atom and h is adjacent to it."}, {"title": "Drawing Lewis Structures Example #2.txt", "text": "So we connect our atoms, and now we are left with four balance electrons."}, {"title": "Drawing Lewis Structures Example #2.txt", "text": "Because we begin with eight balance electrons."}, {"title": "Drawing Lewis Structures Example #2.txt", "text": "We use up 12348."}, {"title": "Drawing Lewis Structures Example #2.txt", "text": "Minus four is four."}, {"title": "Drawing Lewis Structures Example #2.txt", "text": "And because these orbitals are filled, we are left with filling."}, {"title": "Drawing Lewis Structures Example #2.txt", "text": "The N orbitals."}, {"title": "Drawing Lewis Structures Example #2.txt", "text": "So we basically put two here."}, {"title": "Drawing Lewis Structures Example #2.txt", "text": "We place two here and we conclude our drawing."}, {"title": "Drawing Lewis Structures Example #2.txt", "text": "Because now we have 1234-5678 balance electrons."}, {"title": "Drawing Lewis Structures Example #2.txt", "text": "We have four bonding and four non bonding electrons."}, {"title": "Drawing Lewis Structures Example #2.txt", "text": "And because nitrogen is normally used to having five electrons, and in this case it has 123-4456, this end will have a negative one charge."}, {"title": "Drawing Lewis Structures Example #2.txt", "text": "Since the HS have a neutral charge, an overall charge of negative one exists."}, {"title": "Drawing Lewis Structures Example #2.txt", "text": "And this is, in fact, the correct Lewis Dot structure for NH Two Negative One."}, {"title": "Root Mean Square Velocity .txt", "text": "Mathematics\n\nand specifically statistics, root, mean square of any set of values is used to find the average of numbers when you only want to worry about the magnitude and not the size."}, {"title": "Root Mean Square Velocity .txt", "text": "Now let's look at two sets of values."}, {"title": "Root Mean Square Velocity .txt", "text": "In my first set I have 21012, in my second set I have negative two, two negative 1012."}, {"title": "Root Mean Square Velocity .txt", "text": "I want to take the average of, or find the average of this set."}, {"title": "Root Mean Square Velocity .txt", "text": "And this set, well, I add up all my values, divide them by five and get six over five."}, {"title": "Root Mean Square Velocity .txt", "text": "And the same thing for this guy, negative one, negative one, negative two minus negative one plus zero, plus one plus two divided by five."}, {"title": "Root Mean Square Velocity .txt", "text": "Well, these guys cancel and I get zero."}, {"title": "Root Mean Square Velocity .txt", "text": "Now look, in this set all my numbers have the same magnitude as these guys."}, {"title": "Root Mean Square Velocity .txt", "text": "But in this set, these first two numbers have the same magnitude as these first two numbers, but different signs."}, {"title": "Root Mean Square Velocity .txt", "text": "And that's why my average is zero."}, {"title": "Root Mean Square Velocity .txt", "text": "So in some cases, this type of average won't make sense."}, {"title": "Root Mean Square Velocity .txt", "text": "Now, from a fitness perspective, let's look at moving cars."}, {"title": "Root Mean Square Velocity .txt", "text": "Suppose a car is traveling in this direction at 60."}, {"title": "Root Mean Square Velocity .txt", "text": "Suppose in this direction is a positive direction."}, {"title": "Root Mean Square Velocity .txt", "text": "Now suppose another car is also traveling 60 mph, but in the other direction, so it's negative 60, where 60 is our magnitude and direction is our negative sign."}, {"title": "Root Mean Square Velocity .txt", "text": "So if someone asks you what is the average of the first two cars, from a physics perspective you will say 60 mph."}, {"title": "Root Mean Square Velocity .txt", "text": "Because if one car is going 60 and the other car is going 60, then the average must be 60."}, {"title": "Root Mean Square Velocity .txt", "text": "Well, if you use the formula to find the average from a mathematics point of view, you will see that it's 60 plus -60, gives you zero divided by two, which is zero."}, {"title": "Root Mean Square Velocity .txt", "text": "So sometimes from a mathematics point of view, taking the average in the same way that you did here doesn't make sense."}, {"title": "Root Mean Square Velocity .txt", "text": "Because in the real world, if you have two cars traveling at some speed and you take their average, how can the average be zero?"}, {"title": "Root Mean Square Velocity .txt", "text": "So that's where the root mean square formula comes from."}, {"title": "Root Mean Square Velocity .txt", "text": "What this formula does is it takes away these negatives and gives you the value of this type of average without the negatives."}, {"title": "Root Mean Square Velocity .txt", "text": "So let's look at the formula."}, {"title": "Root Mean Square Velocity .txt", "text": "VRS is equal to, you take the squares of every single velocity or every single value and then you divide that by n. So almost the same thing as you did here, except you square every value."}, {"title": "Root Mean Square Velocity .txt", "text": "The reason you square every value is because a square will take away that negative sign and then you divide by n and you take the square root of that."}, {"title": "Root Mean Square Velocity .txt", "text": "So this will always give you a positive value."}, {"title": "Root Mean Square Velocity .txt", "text": "So let's take this example and let's use these two values to find our average."}, {"title": "Root Mean Square Velocity .txt", "text": "So BRMs is equal to 60 mph squared plus negative 60 mph squared."}, {"title": "Root Mean Square Velocity .txt", "text": "This gives you 3600 plus negative canceled."}, {"title": "Root Mean Square Velocity .txt", "text": "So 3600 gives you 7200 divided by two and square root, that gives you 60 mph."}, {"title": "Root Mean Square Velocity .txt", "text": "So you see, once again, that the purpose of the route means square is to take away those negative signs and just give you the magnitude."}, {"title": "Root Mean Square Velocity .txt", "text": "And this becomes useful when you're talking about velocities."}, {"title": "Root Mean Square Velocity .txt", "text": "Because if a molecule is traveling with one velocity this way and another molecule is traveling with the same velocity but the direction the other way, you want to take those averages and you want those averages to give you a positive value, not zero."}, {"title": "Root Mean Square Velocity .txt", "text": "That's exactly why you use root mean square velocity."}, {"title": "Root Mean Square Velocity .txt", "text": "So you see that this guy gives you 60 just like it would from a logical physics perspective."}, {"title": "Root Mean Square Velocity .txt", "text": "From a pure mathematical perspective, it gives you zero if you use the formula."}, {"title": "Root Mean Square Velocity .txt", "text": "Now, one last thing I want to mention is that this definition of velocity is not actually correct."}, {"title": "Root Mean Square Velocity .txt", "text": "Because remember, velocity is a vector."}, {"title": "Root Mean Square Velocity .txt", "text": "That means it has both magnitude and direction."}, {"title": "Root Mean Square Velocity .txt", "text": "While speed is a scaling, it only has magnitude."}, {"title": "Root Mean Square Velocity .txt", "text": "Now, this velocity only has magnitude."}, {"title": "Root Mean Square Velocity .txt", "text": "It doesn't have direction."}, {"title": "Root Mean Square Velocity .txt", "text": "Because when we take the square root, we can't get a negative, so we always get positive."}, {"title": "Root Mean Square Velocity .txt", "text": "So VR mess is not the velocity, it's the root mean square speed."}, {"title": "Root Mean Square Velocity .txt", "text": "Because our velocity, this guy is actually our speed, it only has magnitude."}, {"title": "Root Mean Square Velocity .txt", "text": "So this, this guy is a scaler."}, {"title": "First Law of Thermodynamics .txt", "text": "So today we're going to talk about the first law of thermodynamics, the second law of thermodynamics and the heat engine."}, {"title": "First Law of Thermodynamics .txt", "text": "So the first law of thermodynamics is an extension from the law of conservation of energy which states that energy cannot be created, it cannot be destroyed, it must be transformed from one form to another."}, {"title": "First Law of Thermodynamics .txt", "text": "Now, when we talk about the first law of thermodynamics, we basically, basically talk about closed systems."}, {"title": "First Law of Thermodynamics .txt", "text": "Now, aside from closed systems, they're open systems as well as isolated systems."}, {"title": "First Law of Thermodynamics .txt", "text": "Within a closed system, matter or mass is not allowed to exchange."}, {"title": "First Law of Thermodynamics .txt", "text": "The mass remains constant within the system."}, {"title": "First Law of Thermodynamics .txt", "text": "What is allowed to exchange, however, is energy."}, {"title": "First Law of Thermodynamics .txt", "text": "So energy flows into the system or it can flow out of the system."}, {"title": "First Law of Thermodynamics .txt", "text": "In an isolated system, mass and energy is not allowed to flow anywhere."}, {"title": "First Law of Thermodynamics .txt", "text": "So everything remains constant."}, {"title": "First Law of Thermodynamics .txt", "text": "In an open system, both matter and energy is allowed to exchange."}, {"title": "First Law of Thermodynamics .txt", "text": "Okay?"}, {"title": "First Law of Thermodynamics .txt", "text": "Now when we talk about the transfer of energy, remember that there are only two types of transfer of energy work and heat."}, {"title": "First Law of Thermodynamics .txt", "text": "Now heat can be subdivided into three categories convection, conduction and radiation."}, {"title": "First Law of Thermodynamics .txt", "text": "When we talk about chemical work, we talk about this type of work pressure times change in volume."}, {"title": "First Law of Thermodynamics .txt", "text": "And when pressure remains constant, we use this equation."}, {"title": "First Law of Thermodynamics .txt", "text": "When pressure isn't constant, we use calculus and integrate from the initial to the final."}, {"title": "First Law of Thermodynamics .txt", "text": "Now this law can be summarized in this equation."}, {"title": "First Law of Thermodynamics .txt", "text": "Okay?"}, {"title": "First Law of Thermodynamics .txt", "text": "This law basically translates into this equation."}, {"title": "First Law of Thermodynamics .txt", "text": "And what this equation states is pretty simple."}, {"title": "First Law of Thermodynamics .txt", "text": "All it states is that the energy transfer or energy flow into a system is equal to the heat flow into the system plus the work done on the system."}, {"title": "First Law of Thermodynamics .txt", "text": "What it basically says is that a transfer of energy amounts to two types of transfers."}, {"title": "First Law of Thermodynamics .txt", "text": "Transfers due to heat or transfers due to work."}, {"title": "First Law of Thermodynamics .txt", "text": "Okay, no other transfer of energy exists."}, {"title": "First Law of Thermodynamics .txt", "text": "So let's see what heat engines are."}, {"title": "First Law of Thermodynamics .txt", "text": "Heat engines are basically systems or mechanisms that convert one form of energy into a second form of energy, namely heat into work."}, {"title": "First Law of Thermodynamics .txt", "text": "And this occurs under constant temperature."}, {"title": "First Law of Thermodynamics .txt", "text": "So let's see what the layout of a heat engine is."}, {"title": "First Law of Thermodynamics .txt", "text": "A heat engine is composed of a long cylindrical tube that contains molecules inside this area and that contains a movable piston controlled by an outside force, maybe your hand that's moving it up or down."}, {"title": "First Law of Thermodynamics .txt", "text": "It also contains a hot body connected to the bottom."}, {"title": "First Law of Thermodynamics .txt", "text": "This hot body is important in conduction because remember, conduction requires for physical contact between two systems."}, {"title": "First Law of Thermodynamics .txt", "text": "And conduction allows heat transfer or energy transfer from a hot object to a cold object."}, {"title": "First Law of Thermodynamics .txt", "text": "So let's see what the result is of constant pressure."}, {"title": "First Law of Thermodynamics .txt", "text": "From this formula we see that kinetic energy is related to KB, which is a constant and number of particles and T temperature."}, {"title": "First Law of Thermodynamics .txt", "text": "Now, the number of particles remains constant because this is a closed system."}, {"title": "First Law of Thermodynamics .txt", "text": "Remember, a closed system is a system in which the mass or matter or the number of particles remains constant."}, {"title": "First Law of Thermodynamics .txt", "text": "So n remains constant."}, {"title": "First Law of Thermodynamics .txt", "text": "These guys remain constant, and temperature remains constant."}, {"title": "First Law of Thermodynamics .txt", "text": "So that means kinetic energy also must remain constant."}, {"title": "First Law of Thermodynamics .txt", "text": "Okay, so what's the result?"}, {"title": "First Law of Thermodynamics .txt", "text": "Remember, normally, when there's a transfer of energy, the energy is transferred into increasing the kinetic energy."}, {"title": "First Law of Thermodynamics .txt", "text": "But in this situation, there is no increase in kinetic energy."}, {"title": "First Law of Thermodynamics .txt", "text": "So the question remains, where does this energy transfer go into if it doesn't go into the kinetic energy?"}, {"title": "First Law of Thermodynamics .txt", "text": "Okay, the answer lies in this equation."}, {"title": "First Law of Thermodynamics .txt", "text": "We see that by the ideal Gas Law, PV, or pressure times volume equals number of moles times the constant times the temperature in Kelvin."}, {"title": "First Law of Thermodynamics .txt", "text": "Okay?"}, {"title": "First Law of Thermodynamics .txt", "text": "So this guy remains constant because the temperature remains constant."}, {"title": "First Law of Thermodynamics .txt", "text": "And these guys are constants."}, {"title": "First Law of Thermodynamics .txt", "text": "This is constant because this is a closed system."}, {"title": "First Law of Thermodynamics .txt", "text": "So this must mean that the energy transfer must go into increasing the volume or expanding it."}, {"title": "First Law of Thermodynamics .txt", "text": "And the expansion creates a larger D or a larger volume."}, {"title": "First Law of Thermodynamics .txt", "text": "And because this guy is constant, this must be constant."}, {"title": "First Law of Thermodynamics .txt", "text": "So an increase in D must mean a decrease in P. A decrease in P will decrease."}, {"title": "First Law of Thermodynamics .txt", "text": "Obviously, this P, and look, p, or pressure, is equal to force comes area."}, {"title": "First Law of Thermodynamics .txt", "text": "Area remains constant, because if you take the cross sectional area of this cylinder, it doesn't change as the piston moves up or down."}, {"title": "First Law of Thermodynamics .txt", "text": "So if this guy is constant and this guy is decreasing, the pressure is decreasing, then the force must also decrease."}, {"title": "First Law of Thermodynamics .txt", "text": "So we see that in a heat engine, when the piston is moving, the force is changing, and so is pressure, and so is volume, but temperature remains the same."}, {"title": "First Law of Thermodynamics .txt", "text": "Okay, so what this basically means, or what this basically implies, is that heat must be converted to work, and all the heat must be converted to work."}, {"title": "First Law of Thermodynamics .txt", "text": "But that's actually not true, and only about 10% to 20% normally is converted to work."}, {"title": "First Law of Thermodynamics .txt", "text": "Okay, and let's see why."}, {"title": "First Law of Thermodynamics .txt", "text": "Well, let's go back here."}, {"title": "First Law of Thermodynamics .txt", "text": "When the energy is transferred into this system, this system, the volume increases because the piston starts moving this way, and it continues moving this way until when?"}, {"title": "First Law of Thermodynamics .txt", "text": "Until it hits this limit here, because the cylinder eventually ends when it reaches this place."}, {"title": "First Law of Thermodynamics .txt", "text": "You have this picture here, okay?"}, {"title": "First Law of Thermodynamics .txt", "text": "And now what happens?"}, {"title": "First Law of Thermodynamics .txt", "text": "Now we need to somehow move this piston back to its original location so the process could repeat."}, {"title": "First Law of Thermodynamics .txt", "text": "So this is a cyclic process, right?"}, {"title": "First Law of Thermodynamics .txt", "text": "We want energy to go into here to move the piston this way."}, {"title": "First Law of Thermodynamics .txt", "text": "Then we want to move the piston back this way, and this to continues, okay?"}, {"title": "First Law of Thermodynamics .txt", "text": "Indefinitely."}, {"title": "First Law of Thermodynamics .txt", "text": "But let's see what happens here."}, {"title": "First Law of Thermodynamics .txt", "text": "When we have a force and we start pushing with the force this way, what happens to the kinetic energy or the temperature of the particles within this system?"}, {"title": "First Law of Thermodynamics .txt", "text": "Well, when you move this way, pressure increases, volume decreases, and the particles get closer together."}, {"title": "First Law of Thermodynamics .txt", "text": "They start banging against each other more violently, more frequently."}, {"title": "First Law of Thermodynamics .txt", "text": "This, in turn, increases temperature, which in turn increases kinetic energy, but we saw that we want to have constant temperature."}, {"title": "First Law of Thermodynamics .txt", "text": "Okay, so what does this mean?"}, {"title": "First Law of Thermodynamics .txt", "text": "While this increase in temperature means that there is an increase in pressure and there's an increase in the force, so not the force that we require or the net force that we require to move from this point to this point is greater than the force required to move from this point to this point."}, {"title": "First Law of Thermodynamics .txt", "text": "So the work that's required to move depiction from this position to this position is less than the work required to move from this position to this position."}, {"title": "First Law of Thermodynamics .txt", "text": "And that's not something we want."}, {"title": "First Law of Thermodynamics .txt", "text": "We want to be efficient, and that's not very efficient."}, {"title": "First Law of Thermodynamics .txt", "text": "So how do we fix this system?"}, {"title": "First Law of Thermodynamics .txt", "text": "Well, we fix the system by adding another object to the heat engine, something called a cold body."}, {"title": "First Law of Thermodynamics .txt", "text": "We saw that we had a hot body for the specific purpose of conduction."}, {"title": "First Law of Thermodynamics .txt", "text": "Well, now we have a cold body that also is specific for conduction."}, {"title": "First Law of Thermodynamics .txt", "text": "In other words, when this piston moves this way, there's an increase in temperature."}, {"title": "First Law of Thermodynamics .txt", "text": "And the increase in temperature causes energy to transfer via conduction from this place to this place."}, {"title": "First Law of Thermodynamics .txt", "text": "And this makes the temperature stay constant."}, {"title": "First Law of Thermodynamics .txt", "text": "Okay, so the final outcome is that a heat engine needs to look like this."}, {"title": "First Law of Thermodynamics .txt", "text": "A heat engine needs to have a hot body, a cold body, a cylindrical tube, as well as a piston that's controlled by some outside force."}, {"title": "First Law of Thermodynamics .txt", "text": "And this directly jumps into the second law of thermodynamics."}, {"title": "Cell voltage and Gibbs free energy .txt", "text": "Electrical potential difference, also known as electromotive force, or simply cell voltage, is the difference in voltage between the anode and a cathode of an electrochemical cell or a voltaic cell."}, {"title": "Cell voltage and Gibbs free energy .txt", "text": "Now, this difference in voltage between the anode and a cathode allows these electrons to flow from the anode to the cathode."}, {"title": "Cell voltage and Gibbs free energy .txt", "text": "A positive cell voltage indicates that our reaction within our electrochemical cell is product favorite, so it's spontaneous."}, {"title": "Cell voltage and Gibbs free energy .txt", "text": "Likewise, a negative cell voltage indicates a reactant favorite reaction."}, {"title": "Cell voltage and Gibbs free energy .txt", "text": "Recall that Gibbs free energy builds a relationship between entropy and entropy, and it also dictates whether a reaction is product favorite or reactant favorite."}, {"title": "Cell voltage and Gibbs free energy .txt", "text": "So notice that both cell voltage of an electrochemical cell and GIBS free energy dictate whether or not a reaction is product favorite."}, {"title": "Cell voltage and Gibbs free energy .txt", "text": "So therefore, we can imagine that there's some type of relationship between cell voltage and gives free energy."}, {"title": "Cell voltage and Gibbs free energy .txt", "text": "Now, when gives free energy is positive, that means our reaction is reacting favorite."}, {"title": "Cell voltage and Gibbs free energy .txt", "text": "It's not spontaneous."}, {"title": "Cell voltage and Gibbs free energy .txt", "text": "But when it's negative, the reaction is product favorite."}, {"title": "Cell voltage and Gibbs free energy .txt", "text": "It is spontaneous."}, {"title": "Cell voltage and Gibbs free energy .txt", "text": "Now, before we actually build a relationship and show how the cell voltage relates to GIBS free energy, let's examine something called electrical work."}, {"title": "Cell voltage and Gibbs free energy .txt", "text": "Now, we already spoke about electrical work when we spoke about electromotive force, but let's revisit this topic because it becomes important."}, {"title": "Cell voltage and Gibbs free energy .txt", "text": "So voltaic cells or electrochemical cells convert chemical energy into electrical potential energy that can be used to do work, for example, para light bulb or para motor."}, {"title": "Cell voltage and Gibbs free energy .txt", "text": "Now, this electrical potential energy is also known as electrical work."}, {"title": "Cell voltage and Gibbs free energy .txt", "text": "And we can express electrical work mathematically by equaling this guy to charge of an object or a system times our cell voltage."}, {"title": "Cell voltage and Gibbs free energy .txt", "text": "So if we're talking about cells and electrochemical cells, our charge refers to all the possible charge in our battery in our chemical cell or electric chemical cells."}, {"title": "Cell voltage and Gibbs free energy .txt", "text": "Now, recall that a single electron has a charge of 1.622\ntimes ten to negative 19 Coulombs."}, {"title": "Cell voltage and Gibbs free energy .txt", "text": "This is per electron per one electron."}, {"title": "Cell voltage and Gibbs free energy .txt", "text": "But obviously, a single battery, a single electrochemical cell, has many electrons within itself."}, {"title": "Cell voltage and Gibbs free energy .txt", "text": "That means we're dealing with a lot of these guys."}, {"title": "Cell voltage and Gibbs free energy .txt", "text": "Now, let's find how much charge is in 1 mol of electrons."}, {"title": "Cell voltage and Gibbs free energy .txt", "text": "Right?"}, {"title": "Cell voltage and Gibbs free energy .txt", "text": "The way we do it is we use avogadjo's number."}, {"title": "Cell voltage and Gibbs free energy .txt", "text": "Remember, avogadjo's number refers to the number of atoms or electrons found in 1 mol of anything."}, {"title": "Cell voltage and Gibbs free energy .txt", "text": "Now, we're talking about 1 mol of electrons."}, {"title": "Cell voltage and Gibbs free energy .txt", "text": "That means we take this number of electrons and we multiply by our charge per electron."}, {"title": "Cell voltage and Gibbs free energy .txt", "text": "We see that averagadro's number of electrons per mole times 1.622 times ten to the negative 19 kilos per electron, which we got from here."}, {"title": "Cell voltage and Gibbs free energy .txt", "text": "The electrons cancel, and we get our units to be Coulomb per mole."}, {"title": "Cell voltage and Gibbs free energy .txt", "text": "So the charge of a single mole of electron electrons is 96,484 Coulombs per mole of electron."}, {"title": "Cell voltage and Gibbs free energy .txt", "text": "So when we have 6.22 times ten to the 23 electrons in our cell, that means our cell has a charge of 96,484 klombs."}, {"title": "Cell voltage and Gibbs free energy .txt", "text": "So we can represent this equation in another way."}, {"title": "Cell voltage and Gibbs free energy .txt", "text": "So, this equation electrical work is equal to n, the number of moles times f. Now, f is Faraday's constant."}, {"title": "Cell voltage and Gibbs free energy .txt", "text": "This is known as this number is known as Faraday's constant."}, {"title": "Cell voltage and Gibbs free energy .txt", "text": "And it talks about a charge of one coulomb per mole of electrons."}, {"title": "Cell voltage and Gibbs free energy .txt", "text": "So, once again, f is Faradays constant times our cell voltage."}, {"title": "Cell voltage and Gibbs free energy .txt", "text": "So this n times f is simply charge."}, {"title": "Cell voltage and Gibbs free energy .txt", "text": "It's the same thing."}, {"title": "Cell voltage and Gibbs free energy .txt", "text": "Now, for example, if we have 1 mol in our cell, that means we multiply 1 mol times f.\nSo 1 mol times this guy gives us the most cancel, and we simply get our charge."}, {"title": "Cell voltage and Gibbs free energy .txt", "text": "So n times f is our charge."}, {"title": "Cell voltage and Gibbs free energy .txt", "text": "Now, this equation becomes important when we build a relationship between our cell voltage and gear spree energy."}, {"title": "Cell voltage and Gibbs free energy .txt", "text": "So let's see what the relationship is."}, {"title": "Cell voltage and Gibbs free energy .txt", "text": "So, let's finally examine and see what the relationship is between cell voltage and changing gear free energy."}, {"title": "Cell voltage and Gibbs free energy .txt", "text": "Well, we see that changing gear's free energy is equal to negative of electrical work done."}, {"title": "Cell voltage and Gibbs free energy .txt", "text": "Well, why is that?"}, {"title": "Cell voltage and Gibbs free energy .txt", "text": "Well, this guy is simply the amount of free energy available to do useful work, while with this guy, the electrical work is the amount of energy transformed from chemical energy to electrical energy in the form of moving electrons."}, {"title": "Cell voltage and Gibbs free energy .txt", "text": "And this is also energy used to do useful work."}, {"title": "Cell voltage and Gibbs free energy .txt", "text": "So that's why the magnitude of these guys is the same, but the sign is different."}, {"title": "Cell voltage and Gibbs free energy .txt", "text": "So, why is it that we have a negative sign in front of the electrical work?"}, {"title": "Cell voltage and Gibbs free energy .txt", "text": "Well, let's see why."}, {"title": "Cell voltage and Gibbs free energy .txt", "text": "The negative sign accounts for the fact that for a product favorite reaction, changing gibsi energy is negative while cell voltage is positive."}, {"title": "Cell voltage and Gibbs free energy .txt", "text": "So that's why we need to add that negative sign in."}, {"title": "Cell voltage and Gibbs free energy .txt", "text": "So, from before, we saw that electrical work is equal to number of moles times starbase constant times our cell voltage."}, {"title": "Cell voltage and Gibbs free energy .txt", "text": "So change and gives the energy is equal to negative m times f times cell voltage."}, {"title": "Cell voltage and Gibbs free energy .txt", "text": "So that's our reaction."}, {"title": "Cell voltage and Gibbs free energy .txt", "text": "That's our equation."}, {"title": "Cell voltage and Gibbs free energy .txt", "text": "Now, suppose we have an electrochemical cell able to take cell that's composed of the following redox reaction."}, {"title": "Cell voltage and Gibbs free energy .txt", "text": "So it has an oxidation reaction and a reduction reaction."}, {"title": "Cell voltage and Gibbs free energy .txt", "text": "Our zinc solid is oxidized into zinc ion, while our copper ion is reduced to copper solid."}, {"title": "Cell voltage and Gibbs free energy .txt", "text": "So, this guy releases two electrons, while this guy takes those two electrons, gains two electrons forming our copper solid."}, {"title": "Cell voltage and Gibbs free energy .txt", "text": "Now, these electrons in the end, end up crossing out."}, {"title": "Cell voltage and Gibbs free energy .txt", "text": "Now, our cell voltage is 1.1 volt."}, {"title": "Cell voltage and Gibbs free energy .txt", "text": "So let's use this formula to approximate how much energy this battery or this electrochemical cell can produce with the charge that it has."}, {"title": "Cell voltage and Gibbs free energy .txt", "text": "So, the change in gates free energy is equal to negative of the number of moles of electrons."}, {"title": "Cell voltage and Gibbs free energy .txt", "text": "Well, in this case, I specifically left these guys in to show you how many moles of electrons we have."}, {"title": "Cell voltage and Gibbs free energy .txt", "text": "Well, zinc loses two moles of electrons, and this guy gains two moles of electrons."}, {"title": "Cell voltage and Gibbs free energy .txt", "text": "That means we're dealing with two moles of electrons times our Faradays constant 96,500 approximately Coulombs per mole of electron times our cell voltage or electromotive force 1.1 volt."}, {"title": "Cell voltage and Gibbs free energy .txt", "text": "We see that these guys cancel out and our units are left Coulombs times voltage, which is simply joules."}, {"title": "Cell voltage and Gibbs free energy .txt", "text": "So in the end we get 212,300 joules of work."}, {"title": "Cell voltage and Gibbs free energy .txt", "text": "It's produced is released in the form of moving electrons or moving charge from the anode to the capital from this battery."}, {"title": "Cell voltage and Gibbs free energy .txt", "text": "And this amount of energy can be used to do useful work."}, {"title": "Cell voltage and Gibbs free energy .txt", "text": "For example, run a motor or power a light bulb, for example."}, {"title": "Cell voltage and Gibbs free energy .txt", "text": "So this becomes very useful and we'll do many more examples using this in the future."}, {"title": "Cell voltage and Gibbs free energy .txt", "text": "So I already spoke about this briefly in another lecture, but I want to talk about it once more."}, {"title": "Cell voltage and Gibbs free energy .txt", "text": "Now, the reason that a D battery has more energy than AAA battery is not because a difference of cell voltage."}, {"title": "Cell voltage and Gibbs free energy .txt", "text": "In fact, the cell voltage for this guy and this guy are the same."}, {"title": "Cell voltage and Gibbs free energy .txt", "text": "It's 1.5\nvolts."}, {"title": "Cell voltage and Gibbs free energy .txt", "text": "You could check the label of the batteries."}, {"title": "Cell voltage and Gibbs free energy .txt", "text": "The reason this is more expensive is because it can do more work."}, {"title": "Cell voltage and Gibbs free energy .txt", "text": "But how can it do more work?"}, {"title": "Cell voltage and Gibbs free energy .txt", "text": "Well, because this guy has a larger end, it has more electrons than this guy, it has a larger charge."}, {"title": "Cell voltage and Gibbs free energy .txt", "text": "So this guy, for example, can't run a light bulb or power light bulb for 16 minutes while this guy can power a light bulb for much longer because it has more charge, a larger end value than this guy."}, {"title": "Exothermic Reactions, Endothermic Reactions and BDE.txt", "text": "In this lecture, we're going to discuss three important concepts in Organic chemistry known as Exothermic reactions, endothermic reactions, and Bond association energy."}, {"title": "Exothermic Reactions, Endothermic Reactions and BDE.txt", "text": "So let's begin by looking at the following diagram."}, {"title": "Exothermic Reactions, Endothermic Reactions and BDE.txt", "text": "So, we're basically taking two identical H atoms."}, {"title": "Exothermic Reactions, Endothermic Reactions and BDE.txt", "text": "We're combining them to form a Diatomic H two Model molecule."}, {"title": "Exothermic Reactions, Endothermic Reactions and BDE.txt", "text": "So, here are our two identical H atoms."}, {"title": "Exothermic Reactions, Endothermic Reactions and BDE.txt", "text": "So, this is a one s Atomic orbital of the first H atom and the second Atomic orbital of the second H atom."}, {"title": "Exothermic Reactions, Endothermic Reactions and BDE.txt", "text": "So we have an electron in each atomic orbital."}, {"title": "Exothermic Reactions, Endothermic Reactions and BDE.txt", "text": "So, if we combine two Atomic orbitals according to quantum mechanics, we're going to form two molecular orbitals."}, {"title": "Exothermic Reactions, Endothermic Reactions and BDE.txt", "text": "One will be the phi B, which is the Bonding molecular orbital."}, {"title": "Exothermic Reactions, Endothermic Reactions and BDE.txt", "text": "And the second will be the phi A, which is the Anti Bonding molecular orbital."}, {"title": "Exothermic Reactions, Endothermic Reactions and BDE.txt", "text": "Now, the bonding molecular orbital is lower in energy."}, {"title": "Exothermic Reactions, Endothermic Reactions and BDE.txt", "text": "It's more stabilizing."}, {"title": "Exothermic Reactions, Endothermic Reactions and BDE.txt", "text": "And, in fact, this is the bond responsible for forming our covalent bond."}, {"title": "Exothermic Reactions, Endothermic Reactions and BDE.txt", "text": "So our electrons will be found in the Lower Energy bonding molecular orbital."}, {"title": "Exothermic Reactions, Endothermic Reactions and BDE.txt", "text": "So phi b."}, {"title": "Exothermic Reactions, Endothermic Reactions and BDE.txt", "text": "Now, phi A, or Antiboming Molecular Orbital, is responsible for breaking the bond."}, {"title": "Exothermic Reactions, Endothermic Reactions and BDE.txt", "text": "If the electrons are found within this bond, that means those electrons will play a role in Destabilizing our molecule in breaking that Covalent bond."}, {"title": "Exothermic Reactions, Endothermic Reactions and BDE.txt", "text": "Now, so electrons will be found in this bonding molecular orbital."}, {"title": "Exothermic Reactions, Endothermic Reactions and BDE.txt", "text": "And notice what happens."}, {"title": "Exothermic Reactions, Endothermic Reactions and BDE.txt", "text": "Because these two Atomic orbitals are higher in energy than this molecular orbital, energy will Be lost."}, {"title": "Exothermic Reactions, Endothermic Reactions and BDE.txt", "text": "So, there is some change in energy that occurs when these two atomic orbitals form this molecular orbital or this molecular Diatomic molecule."}, {"title": "Exothermic Reactions, Endothermic Reactions and BDE.txt", "text": "Now, this energy is Released into the environment."}, {"title": "Exothermic Reactions, Endothermic Reactions and BDE.txt", "text": "In other words, when my two H atoms form to create a bond, energy is released."}, {"title": "Exothermic Reactions, Endothermic Reactions and BDE.txt", "text": "And, in fact, any time we form bonds, energy will always Be Released into the environment."}, {"title": "Exothermic Reactions, Endothermic Reactions and BDE.txt", "text": "So let's look at this in a more simplified fashion."}, {"title": "Exothermic Reactions, Endothermic Reactions and BDE.txt", "text": "So, here we have two H molecules."}, {"title": "Exothermic Reactions, Endothermic Reactions and BDE.txt", "text": "At some level, they react."}, {"title": "Exothermic Reactions, Endothermic Reactions and BDE.txt", "text": "They surmount this Activation barrier, and they form our Diatomic H two molecule, which is lower in energy than the initial."}, {"title": "Exothermic Reactions, Endothermic Reactions and BDE.txt", "text": "So our products are lower than Our reactants."}, {"title": "Exothermic Reactions, Endothermic Reactions and BDE.txt", "text": "And this change in energy is the same as the change in energy that we saw here."}, {"title": "Exothermic Reactions, Endothermic Reactions and BDE.txt", "text": "Another name for that is change in enthalpy."}, {"title": "Exothermic Reactions, Endothermic Reactions and BDE.txt", "text": "So change in H. And from 1 mol, where whenever 1 mol of H reacts with Another Mole of H to form 1 Mol of H 2104, energy will Be Released Into The environment."}, {"title": "Exothermic Reactions, Endothermic Reactions and BDE.txt", "text": "And this is known as an exothermic reaction."}, {"title": "Exothermic Reactions, Endothermic Reactions and BDE.txt", "text": "In other words, exothermic reaction is A reaction in which the energy of products is lower than the energy of reactants, and the energy is released into the environment."}, {"title": "Exothermic Reactions, Endothermic Reactions and BDE.txt", "text": "Now, let's look at the same Exact diagram."}, {"title": "Exothermic Reactions, Endothermic Reactions and BDE.txt", "text": "But now we're going to work backwards."}, {"title": "Exothermic Reactions, Endothermic Reactions and BDE.txt", "text": "So we basically want to begin with a diatomic H two molecule, and we want to somehow get to this H two."}, {"title": "Exothermic Reactions, Endothermic Reactions and BDE.txt", "text": "So we essentially want to break this covalent bond and form two separate H molecules or h atoms."}, {"title": "Exothermic Reactions, Endothermic Reactions and BDE.txt", "text": "So that means since we go from a lower energy to a higher energy, we have to input energy to go from this guy to this guy."}, {"title": "Exothermic Reactions, Endothermic Reactions and BDE.txt", "text": "So we input energy to break the bond to form two individual H molecules."}, {"title": "Exothermic Reactions, Endothermic Reactions and BDE.txt", "text": "And this is known as an endothermic reaction."}, {"title": "Exothermic Reactions, Endothermic Reactions and BDE.txt", "text": "So once again, endothermic reaction is a reaction in which the energy of product is higher than the end of reactants and energy is used up or inputted into the system for that reaction to take place."}, {"title": "Exothermic Reactions, Endothermic Reactions and BDE.txt", "text": "So once again, anytime we have an endothermic reaction going this way, going the forward direction, we have an endothermic reaction going in the backward or reverse direction."}, {"title": "Exothermic Reactions, Endothermic Reactions and BDE.txt", "text": "So once again, to sum this information up, anytime we form a bond, energy is released."}, {"title": "Exothermic Reactions, Endothermic Reactions and BDE.txt", "text": "Anytime we want to break a bond, energy needs to be inputted into our system, into the molecule."}, {"title": "Exothermic Reactions, Endothermic Reactions and BDE.txt", "text": "Now, what is bond association energy?"}, {"title": "Exothermic Reactions, Endothermic Reactions and BDE.txt", "text": "Well, bond association energy is the amount of energy required to break a bond."}, {"title": "Exothermic Reactions, Endothermic Reactions and BDE.txt", "text": "In other words, if we want to break this bond, we need to input some amount of energy."}, {"title": "Exothermic Reactions, Endothermic Reactions and BDE.txt", "text": "And this is known as the bond association energy."}, {"title": "Exothermic Reactions, Endothermic Reactions and BDE.txt", "text": "So for example, let's compare two molecules or two bonds."}, {"title": "Exothermic Reactions, Endothermic Reactions and BDE.txt", "text": "That Ch bond and the CF bond."}, {"title": "Exothermic Reactions, Endothermic Reactions and BDE.txt", "text": "Now, Ch bond has a bond association of 103 kg/mol."}, {"title": "Exothermic Reactions, Endothermic Reactions and BDE.txt", "text": "In other words, it requires this much energy per mole to break this bond between the C and the H. For a CF, the bond dissociation energy is 110 kilo cals per mole."}, {"title": "Exothermic Reactions, Endothermic Reactions and BDE.txt", "text": "Now, clearly, this bond is more stabilized and that's because more energy is required to break this bond."}, {"title": "Exothermic Reactions, Endothermic Reactions and BDE.txt", "text": "So if we compare this Ch bond and this CF bond, the CF bond will be lower on the energy diagram than the Ch bond because more energy is required to break."}, {"title": "Homo-Lumo Examples .txt", "text": "So in this reaction, we're going to identify the homo and luma orbitals of a few reactions."}, {"title": "Homo-Lumo Examples .txt", "text": "Now, before we look at that, let's recall what homo and luma orbitals are."}, {"title": "Homo-Lumo Examples .txt", "text": "Now, recall that a lewis acidbased reaction is simply a reaction between the highest occupied molecular orbital known as the homo of one kind compound, and the lowest unoccupied molecular orbital of a second compound known as the lumo."}, {"title": "Homo-Lumo Examples .txt", "text": "So we basically have a pair of electrons, grams, another molecule, or compound."}, {"title": "Homo-Lumo Examples .txt", "text": "So let's look at the following reaction."}, {"title": "Homo-Lumo Examples .txt", "text": "So here we have an amine."}, {"title": "Homo-Lumo Examples .txt", "text": "We have ammonia that reacts with our H plus ion."}, {"title": "Homo-Lumo Examples .txt", "text": "So our lewis acid and lewis base."}, {"title": "Homo-Lumo Examples .txt", "text": "So here we have our molecular orbital that is occupied."}, {"title": "Homo-Lumo Examples .txt", "text": "It has a pair of electrons which grab this unoccupied orbital, one s orbital."}, {"title": "Homo-Lumo Examples .txt", "text": "So this SP three hybridized molecular orbital is our homo."}, {"title": "Homo-Lumo Examples .txt", "text": "It's the highest occupied molecular orbital."}, {"title": "Homo-Lumo Examples .txt", "text": "While on this molecule, or actually atom, our lowest unoccupied molecular orbital is the one S orbital."}, {"title": "Homo-Lumo Examples .txt", "text": "Because we're missing an electron, we have a cat ion."}, {"title": "Homo-Lumo Examples .txt", "text": "So we have an MP, one S orbital."}, {"title": "Homo-Lumo Examples .txt", "text": "So this is our lumo, or lowest unoccupied molecular orbital."}, {"title": "Homo-Lumo Examples .txt", "text": "So when these two orbitals interact, so we have the SP three interacting with the one S, and we form the following two orbitals."}, {"title": "Homo-Lumo Examples .txt", "text": "We form the bonding molecular orbital and the anti bonding molecular orbital."}, {"title": "Homo-Lumo Examples .txt", "text": "Now, since this orbital is lower in energy, that means our electron pair coming from this highest occupied molecular orbital goes directly into this bonding molecular orbital."}, {"title": "Homo-Lumo Examples .txt", "text": "So let's look at a few more examples."}, {"title": "Homo-Lumo Examples .txt", "text": "Now, let's suppose we have example a."}, {"title": "Homo-Lumo Examples .txt", "text": "In this reaction, we have a hydroxide with a negative sign interacting with a sodium ion with a positive sign, and we form sodium hydroxide."}, {"title": "Homo-Lumo Examples .txt", "text": "So which one has the homo and which one has the lumo?"}, {"title": "Homo-Lumo Examples .txt", "text": "So clearly, this is our base."}, {"title": "Homo-Lumo Examples .txt", "text": "Why?"}, {"title": "Homo-Lumo Examples .txt", "text": "Well, because it has a pair of electrons that it can donate that it can use to grab another molecule, in this case, atom."}, {"title": "Homo-Lumo Examples .txt", "text": "So that means this pair of electrons, the orbital that is found in, must be the homo."}, {"title": "Homo-Lumo Examples .txt", "text": "So the highest occupied molecular orbital is the field non bonding SP three hybridized orbital molecular orbital."}, {"title": "Homo-Lumo Examples .txt", "text": "So what's the lumo in our case?"}, {"title": "Homo-Lumo Examples .txt", "text": "Well, if this is the homo, this must be the lumo."}, {"title": "Homo-Lumo Examples .txt", "text": "So the lowest unoccupied molecular orbital is the empty three s orbital of our sodium atom."}, {"title": "Homo-Lumo Examples .txt", "text": "Let's move on to example two."}, {"title": "Homo-Lumo Examples .txt", "text": "Reaction two."}, {"title": "Homo-Lumo Examples .txt", "text": "Here we have a hydronium acid reacting with our hydroxide base, forming two H, two O molecules."}, {"title": "Homo-Lumo Examples .txt", "text": "So which one is the homo and which one is the lumo?"}, {"title": "Homo-Lumo Examples .txt", "text": "Now, this one is a bit tricky, and we'll see why in a second."}, {"title": "Homo-Lumo Examples .txt", "text": "So let's begin with homo."}, {"title": "Homo-Lumo Examples .txt", "text": "So the homo has the highest or is the highest occupied molecular orbital."}, {"title": "Homo-Lumo Examples .txt", "text": "And that means our hydroxide has a lone pair of electrons, so it must have the homo."}, {"title": "Homo-Lumo Examples .txt", "text": "So our filled non bonding orbital of the oh is our homo and it's SP three hybridized."}, {"title": "Homo-Lumo Examples .txt", "text": "So it's the same exact homo that we saw in example A."}, {"title": "Homo-Lumo Examples .txt", "text": "Now, what's the lumo?"}, {"title": "Homo-Lumo Examples .txt", "text": "Well, if we examine our hydronium ion, we see that every single orbital is taken."}, {"title": "Homo-Lumo Examples .txt", "text": "Every single bonding orbital is taken."}, {"title": "Homo-Lumo Examples .txt", "text": "We have the three bonds."}, {"title": "Homo-Lumo Examples .txt", "text": "And we have a pair of electrons which aren't drawn."}, {"title": "Homo-Lumo Examples .txt", "text": "Here, let me fill them in."}, {"title": "Homo-Lumo Examples .txt", "text": "We have a pair of electrons on this oxygen."}, {"title": "Homo-Lumo Examples .txt", "text": "So all four types of orbitals are filled."}, {"title": "Homo-Lumo Examples .txt", "text": "So that means if we don't have our bonding orbitals our Sigma bonding, we must use our Sigma antibodies."}, {"title": "Homo-Lumo Examples .txt", "text": "So the lowest unoccupied molecular orbital is the anti unoccupied Sigma antibonding orbital of one of the ho bonds."}, {"title": "Homo-Lumo Examples .txt", "text": "Now, let's go to example C. An example C.\nWe have an alkane reacting with our hydrobromic acid to form the following carbocation with a positive charge."}, {"title": "Homo-Lumo Examples .txt", "text": "And our bromine an ion."}, {"title": "Homo-Lumo Examples .txt", "text": "So which one is the homo?"}, {"title": "Homo-Lumo Examples .txt", "text": "Which one is the lumo?"}, {"title": "Homo-Lumo Examples .txt", "text": "So which one of these is doing the donating?"}, {"title": "Homo-Lumo Examples .txt", "text": "Which one is using its electron pair?"}, {"title": "Homo-Lumo Examples .txt", "text": "So clearly it's the alkene."}, {"title": "Homo-Lumo Examples .txt", "text": "This pair of electrons in the Pi bond is used to attract or take this H atom from our bromine."}, {"title": "Homo-Lumo Examples .txt", "text": "So that means our highest occupied molecular orbital is the pi bond."}, {"title": "Homo-Lumo Examples .txt", "text": "The pi bonding of the carbon carbon double bond."}, {"title": "Homo-Lumo Examples .txt", "text": "So our homo is the pi bond."}, {"title": "Homo-Lumo Examples .txt", "text": "What about our lumo?"}, {"title": "Homo-Lumo Examples .txt", "text": "So once again, our lumo must be on this molecule."}, {"title": "Homo-Lumo Examples .txt", "text": "But notice that the Sigma bonding orbital is taking."}, {"title": "Homo-Lumo Examples .txt", "text": "So that means we must go to the next unoccupied orbital."}, {"title": "Homo-Lumo Examples .txt", "text": "So we're dealing with an anti bonding."}, {"title": "Homo-Lumo Examples .txt", "text": "And so the lumo, the lowest unoccupied molecular orbital is the unoccupied antibonding Sigma molecular orbital of HBR."}, {"title": "Orthogonal Molecular Orbitals .txt", "text": "So, so far, in our discussion on molecular orbitals, we have combined two atomic one S orbitals of the H atom to form two molecular orbitals."}, {"title": "Orthogonal Molecular Orbitals .txt", "text": "So here we have our two H atoms, the one S orbital and the one S orbital."}, {"title": "Orthogonal Molecular Orbitals .txt", "text": "We combine the two atomic orbitals to form two molecular orbitals, one molecular orbital."}, {"title": "Orthogonal Molecular Orbitals .txt", "text": "The bonding molecular orbital is lower in energy and is stabilizing, while the higher in energy and the destabilizing molecular orbital is called the antibonding molecular orbital."}, {"title": "Orthogonal Molecular Orbitals .txt", "text": "Now, what we haven't done so far is use our electrons."}, {"title": "Orthogonal Molecular Orbitals .txt", "text": "Remember, an electron is found in this atomic orbital, and one electron is found in this atomic orbital."}, {"title": "Orthogonal Molecular Orbitals .txt", "text": "Because we have two identical H atoms, and each are neutral."}, {"title": "Orthogonal Molecular Orbitals .txt", "text": "So each have one neutron, one proton, and one electron."}, {"title": "Orthogonal Molecular Orbitals .txt", "text": "So here we have a positive one half spin."}, {"title": "Orthogonal Molecular Orbitals .txt", "text": "Here we have a negative one half spin."}, {"title": "Orthogonal Molecular Orbitals .txt", "text": "When these two guys combine, where would these two electrons want to go?"}, {"title": "Orthogonal Molecular Orbitals .txt", "text": "In the higher energy or the lower energy?"}, {"title": "Orthogonal Molecular Orbitals .txt", "text": "Remember, nature likes stabilizing states."}, {"title": "Orthogonal Molecular Orbitals .txt", "text": "They like low energy."}, {"title": "Orthogonal Molecular Orbitals .txt", "text": "So that means these two electrons will combine and will go into this bonding molecular orbital."}, {"title": "Orthogonal Molecular Orbitals .txt", "text": "Now, according to the poly exclusion principle, two things must happen."}, {"title": "Orthogonal Molecular Orbitals .txt", "text": "A maximum of two electrons should be found in this orbital, and these guys should have positive one half and negative one half."}, {"title": "Orthogonal Molecular Orbitals .txt", "text": "So opposite spins."}, {"title": "Orthogonal Molecular Orbitals .txt", "text": "And that's exactly what we have here."}, {"title": "Orthogonal Molecular Orbitals .txt", "text": "So these electrons will not want to go into this orbital because this is higher in energy, and it causes the bond to destabilize or break apart."}, {"title": "Orthogonal Molecular Orbitals .txt", "text": "So, once again, this was combining two atomic one s orbitals to form two molecular orbitals."}, {"title": "Orthogonal Molecular Orbitals .txt", "text": "Now, let's combine one S orbital and a two p orbital."}, {"title": "Orthogonal Molecular Orbitals .txt", "text": "Remember, a two p orbital has this eight shape, right?"}, {"title": "Orthogonal Molecular Orbitals .txt", "text": "Okay, so let's look at A."}, {"title": "Orthogonal Molecular Orbitals .txt", "text": "And let's look at B."}, {"title": "Orthogonal Molecular Orbitals .txt", "text": "Here I have two ways two potential ways in which our two atomic orbitals can interact in space."}, {"title": "Orthogonal Molecular Orbitals .txt", "text": "In part A, we have an orthogonal interaction."}, {"title": "Orthogonal Molecular Orbitals .txt", "text": "In part B, we have a non orthogonal interaction."}, {"title": "Orthogonal Molecular Orbitals .txt", "text": "Orthogonal simply means perpendicular."}, {"title": "Orthogonal Molecular Orbitals .txt", "text": "So let's see which one of these is the correct interaction."}, {"title": "Orthogonal Molecular Orbitals .txt", "text": "In other words, which one of these will form molecular bonds, and which one of these will not form molecular bonds."}, {"title": "Orthogonal Molecular Orbitals .txt", "text": "So let's begin with A."}, {"title": "Orthogonal Molecular Orbitals .txt", "text": "Now, remember, this plus and minus does not mean charge."}, {"title": "Orthogonal Molecular Orbitals .txt", "text": "It means, for example, the plus means that we're combining the one s positive orbital and the two p positive orbital."}, {"title": "Orthogonal Molecular Orbitals .txt", "text": "Now, when we combine the two positive orbitals, we get the following figure."}, {"title": "Orthogonal Molecular Orbitals .txt", "text": "When we combine the positive one S orbital and the negative one two p orbital, we get the following interaction."}, {"title": "Orthogonal Molecular Orbitals .txt", "text": "To get the negative two p, we simply switch it or flip it."}, {"title": "Orthogonal Molecular Orbitals .txt", "text": "So here we have our two interactions."}, {"title": "Orthogonal Molecular Orbitals .txt", "text": "So let's look at this guy."}, {"title": "Orthogonal Molecular Orbitals .txt", "text": "So, our positive will want to interact in a bonding way with the positive two p. So positive one s wants to interact with the positive sign of the two P orbital."}, {"title": "Orthogonal Molecular Orbitals .txt", "text": "And likewise at the same time when these guys are interacting in a bonding way, these guys are interacting in an anti bonding way."}, {"title": "Orthogonal Molecular Orbitals .txt", "text": "And that's because we have a positive and a negative."}, {"title": "Orthogonal Molecular Orbitals .txt", "text": "Remember, positive and positive orbitals create bonding interactions."}, {"title": "Orthogonal Molecular Orbitals .txt", "text": "Positive and negative create antibodies."}, {"title": "Orthogonal Molecular Orbitals .txt", "text": "So here we have a bonding and an antiboding."}, {"title": "Orthogonal Molecular Orbitals .txt", "text": "Let's go to this one."}, {"title": "Orthogonal Molecular Orbitals .txt", "text": "Here we have the same exact thing."}, {"title": "Orthogonal Molecular Orbitals .txt", "text": "Even though we flipped our two P orbital, we still have a bonding orbital between the positive one S and the positive two P and we have a negative interaction or an antibiotic interaction because we have a positive one S and a negative two P. So what happens when we have bonding and antiboding?"}, {"title": "Orthogonal Molecular Orbitals .txt", "text": "Well, the bonding will exactly cancel out the antibonding."}, {"title": "Orthogonal Molecular Orbitals .txt", "text": "And that means we will have a net interaction of zero."}, {"title": "Orthogonal Molecular Orbitals .txt", "text": "So orthogonal approach of orbitals."}, {"title": "Orthogonal Molecular Orbitals .txt", "text": "Or this guy does not allow for bonding because the bonding interactions are canceled out by the antibonding interaction."}, {"title": "Orthogonal Molecular Orbitals .txt", "text": "So there will be no interaction when our two atomic orbitals, the one S and the two P approach in this orthogonal fashion."}, {"title": "Orthogonal Molecular Orbitals .txt", "text": "So now let's look at part B."}, {"title": "Orthogonal Molecular Orbitals .txt", "text": "Now we have the following non orthogonal interaction."}, {"title": "Orthogonal Molecular Orbitals .txt", "text": "So once again, let's show our pictures out."}, {"title": "Orthogonal Molecular Orbitals .txt", "text": "So we have the positive one S interact with the positive two P. So we keep the two orientations and we have the following picture."}, {"title": "Orthogonal Molecular Orbitals .txt", "text": "So this is one molecular orbital."}, {"title": "Orthogonal Molecular Orbitals .txt", "text": "And now let's try to do the negative."}, {"title": "Orthogonal Molecular Orbitals .txt", "text": "So we have the one S positive and the two P negative."}, {"title": "Orthogonal Molecular Orbitals .txt", "text": "So we flip the two P and we have the following depiction."}, {"title": "Orthogonal Molecular Orbitals .txt", "text": "Now we have a note or nodal plane symbolized by this black dash here."}, {"title": "Orthogonal Molecular Orbitals .txt", "text": "So we have the positive oneness interacts in an anti bonding fashion with the negative two P and we create this nodal plane which is once again simply our region where the electron density is zero."}, {"title": "Orthogonal Molecular Orbitals .txt", "text": "In other words, electrons will never will have a zero probability to be found in this region here."}, {"title": "Orthogonal Molecular Orbitals .txt", "text": "And notice that we don't have the same situation as we have here."}, {"title": "Orthogonal Molecular Orbitals .txt", "text": "In other words, we simply have bonding and then we have antibonding."}, {"title": "Orthogonal Molecular Orbitals .txt", "text": "So that means that this will be the correct interaction."}, {"title": "Orthogonal Molecular Orbitals .txt", "text": "This is how our two or how our one S and our two P orbitals will interact to form our two molecular orbitals."}, {"title": "Orthogonal Molecular Orbitals .txt", "text": "So we put in two atomic orbitals and we get out two molecular orbitals."}, {"title": "Orthogonal Molecular Orbitals .txt", "text": "And this is our picture here."}, {"title": "Orthogonal Molecular Orbitals .txt", "text": "So this is our energy diagram."}, {"title": "Orthogonal Molecular Orbitals .txt", "text": "So this is our one S orbital."}, {"title": "Orthogonal Molecular Orbitals .txt", "text": "And remember, the two P orbital is slightly higher on the energy level."}, {"title": "Orthogonal Molecular Orbitals .txt", "text": "It's slightly higher."}, {"title": "Orthogonal Molecular Orbitals .txt", "text": "And so that means this guy will be slightly above our energy level of the one S. So we have one electron in the one S and the one electron in the two P.\nThey will interact to form a stabilizing lower in energy bonding molecular orbital and a destabilizing higher in energy antibonding molecular orbital."}, {"title": "Orthogonal Molecular Orbitals .txt", "text": "Now, in the next lecture, we're going to see how two two p orbitals interact to form molecular orbitals."}, {"title": "Cations, Anions and Isoelectronic Atoms .txt", "text": "So suppose we begin with a neutral atom in which the number of electrons equals number of protons."}, {"title": "Cations, Anions and Isoelectronic Atoms .txt", "text": "Now, what that basically means is that if we add up our charges due to our electrons, with the charges due to our protons, we're going to get a net charge or an overall charge of zero."}, {"title": "Cations, Anions and Isoelectronic Atoms .txt", "text": "Now, that's exactly what a neutral atom is."}, {"title": "Cations, Anions and Isoelectronic Atoms .txt", "text": "It's an atom."}, {"title": "Cations, Anions and Isoelectronic Atoms .txt", "text": "Atom in which our charge is zero."}, {"title": "Cations, Anions and Isoelectronic Atoms .txt", "text": "Well, now, suppose we take our atom and our neutral atom gains or loses electrons."}, {"title": "Cations, Anions and Isoelectronic Atoms .txt", "text": "Well, now we have a case in which the number of electrons is no longer equal to the number of protons."}, {"title": "Cations, Anions and Isoelectronic Atoms .txt", "text": "And so we're going to get a charge species called an ion."}, {"title": "Cations, Anions and Isoelectronic Atoms .txt", "text": "Now, whenever we're dealing with metals, be it transition metals, alkaline metals or alkaline earth metals, these guys tend to lose electrons because they can hold onto an electrons very tightly."}, {"title": "Cations, Anions and Isoelectronic Atoms .txt", "text": "They're not very electronegative."}, {"title": "Cations, Anions and Isoelectronic Atoms .txt", "text": "And what that basically means is that they will form ions with positive charges."}, {"title": "Cations, Anions and Isoelectronic Atoms .txt", "text": "And these guys are called Cations."}, {"title": "Cations, Anions and Isoelectronic Atoms .txt", "text": "Now."}, {"title": "Cations, Anions and Isoelectronic Atoms .txt", "text": "On the contrary."}, {"title": "Cations, Anions and Isoelectronic Atoms .txt", "text": "Nonmetal such as the halogens or oxygen or sulfur."}, {"title": "Cations, Anions and Isoelectronic Atoms .txt", "text": "These guys have a very high affinity for electrons."}, {"title": "Cations, Anions and Isoelectronic Atoms .txt", "text": "And that means they will tend to take away electrons from other less electronegative atoms."}, {"title": "Cations, Anions and Isoelectronic Atoms .txt", "text": "And that means they will form ions in which there is a negative charge."}, {"title": "Cations, Anions and Isoelectronic Atoms .txt", "text": "And these guys are called nions."}, {"title": "Cations, Anions and Isoelectronic Atoms .txt", "text": "Now, let's look at the following illustration."}, {"title": "Cations, Anions and Isoelectronic Atoms .txt", "text": "Suppose we have a neutral atom x and this guy takes away the electron from some other atom forming an anion."}, {"title": "Cations, Anions and Isoelectronic Atoms .txt", "text": "Well, this guy will simply have a negative charge represented in the following way now, most nonmetals follow this pathway."}, {"title": "Cations, Anions and Isoelectronic Atoms .txt", "text": "Now, suppose we have the reverse."}, {"title": "Cations, Anions and Isoelectronic Atoms .txt", "text": "Suppose we have an atom x that loses an electrons or loses an electron."}, {"title": "Cations, Anions and Isoelectronic Atoms .txt", "text": "Now, this guy will form a cation or an ion with a positive charge."}, {"title": "Cations, Anions and Isoelectronic Atoms .txt", "text": "Now, most metals follow this pathway."}, {"title": "Cations, Anions and Isoelectronic Atoms .txt", "text": "Now, one note about transition metals."}, {"title": "Cations, Anions and Isoelectronic Atoms .txt", "text": "Transition metals."}, {"title": "Cations, Anions and Isoelectronic Atoms .txt", "text": "Whenever they lose electrons, they first lose electrons from the s orbital and therefore the d orbital."}, {"title": "Cations, Anions and Isoelectronic Atoms .txt", "text": "And that's because the S orbital is at a higher state than the D orbital."}, {"title": "Cations, Anions and Isoelectronic Atoms .txt", "text": "And electrons lose or electrons leave the higher levels first before the lower levels."}, {"title": "Cations, Anions and Isoelectronic Atoms .txt", "text": "Now we're going to talk more about orbitals."}, {"title": "Cations, Anions and Isoelectronic Atoms .txt", "text": "The s orbitals and d orbitals in a future lecture."}, {"title": "Cations, Anions and Isoelectronic Atoms .txt", "text": "So stick around."}, {"title": "Cations, Anions and Isoelectronic Atoms .txt", "text": "Now, what happens to the size of our atom when it loses or gains an electron?"}, {"title": "Cations, Anions and Isoelectronic Atoms .txt", "text": "Well, let's suppose we have a neutral atom that has two protons and two electrons."}, {"title": "Cations, Anions and Isoelectronic Atoms .txt", "text": "And let's look at our illustration."}, {"title": "Cations, Anions and Isoelectronic Atoms .txt", "text": "So one electron on the atomo shell, one electron on the innermost shell, and two plus or two protons down there a nucleus."}, {"title": "Cations, Anions and Isoelectronic Atoms .txt", "text": "So its charge is zero."}, {"title": "Cations, Anions and Isoelectronic Atoms .txt", "text": "Now, suppose it loses an electron."}, {"title": "Cations, Anions and Isoelectronic Atoms .txt", "text": "Let's say it loses our atomos electron."}, {"title": "Cations, Anions and Isoelectronic Atoms .txt", "text": "Well, that means it's going to shrink in size."}, {"title": "Cations, Anions and Isoelectronic Atoms .txt", "text": "And this is why."}, {"title": "Cations, Anions and Isoelectronic Atoms .txt", "text": "Remember, most atoms or atoms are generally composed of empty space."}, {"title": "Cations, Anions and Isoelectronic Atoms .txt", "text": "So when this guy disappears, all this empty space goes with it."}, {"title": "Cations, Anions and Isoelectronic Atoms .txt", "text": "And so it becomes much smaller."}, {"title": "Cations, Anions and Isoelectronic Atoms .txt", "text": "So now the plus two charge will be greater than our negative one charge."}, {"title": "Cations, Anions and Isoelectronic Atoms .txt", "text": "And that means this electron will be pulled even closer to the nucleus, decreasing in size even further."}, {"title": "Cations, Anions and Isoelectronic Atoms .txt", "text": "So when we talk about cations, or when neutral atoms become can ions, there is a loss of electron, and this shrinks the element to a smaller size."}, {"title": "Cations, Anions and Isoelectronic Atoms .txt", "text": "Now, on the contrary, let's look at anions."}, {"title": "Cations, Anions and Isoelectronic Atoms .txt", "text": "So what happens to anion?"}, {"title": "Cations, Anions and Isoelectronic Atoms .txt", "text": "Suppose now we have a neutral atom with a plus one charge and a minus one charge, forming a neutral charge."}, {"title": "Cations, Anions and Isoelectronic Atoms .txt", "text": "And now suppose it gains an electron from some other atom, probably metal."}, {"title": "Cations, Anions and Isoelectronic Atoms .txt", "text": "Now what will happen is it will gain a new outer shell, forming this outer shell and forming this empty space in between."}, {"title": "Cations, Anions and Isoelectronic Atoms .txt", "text": "And that means anions."}, {"title": "Cations, Anions and Isoelectronic Atoms .txt", "text": "When they gain electrons, this causes our atom or element, to grow in size."}, {"title": "Cations, Anions and Isoelectronic Atoms .txt", "text": "So cations, or the formation of cations, decrease the size of our atom, while the formation of anions increases the size of our atom."}, {"title": "Cations, Anions and Isoelectronic Atoms .txt", "text": "Now let's look at one last thing."}, {"title": "Cations, Anions and Isoelectronic Atoms .txt", "text": "Now isoelectronic atoms are those atoms that have the same number of electrons, but different number of protons."}, {"title": "Cations, Anions and Isoelectronic Atoms .txt", "text": "Suppose we have an atom with ten electrons and ten protons, and an atom with ten electrons and eleven protons."}, {"title": "Cations, Anions and Isoelectronic Atoms .txt", "text": "Now, what is the size comparison?"}, {"title": "Cations, Anions and Isoelectronic Atoms .txt", "text": "Well, the atom with more part of the charge with the eleven protons, the nucleus will be able to pull the electrons closer than the other atom that has only ten protons."}, {"title": "Cations, Anions and Isoelectronic Atoms .txt", "text": "And that means when we're talking about isoelectronic atoms that have the same number of electrons, when there is an increase in number of protons, our atom tends to become smaller."}, {"title": "Rate Determining Step and Rate Law Part 1.txt", "text": "Now as of now we've only really spoken about oneway elementary actions in which reactants become products in a single forward step."}, {"title": "Rate Determining Step and Rate Law Part 1.txt", "text": "Now we're going to look at complex reactions and we're going to find the rate laws for complex reactions."}, {"title": "Rate Determining Step and Rate Law Part 1.txt", "text": "Now remember, in complex reactions reactants convert to products in more than one step."}, {"title": "Rate Determining Step and Rate Law Part 1.txt", "text": "So the mechanism of our conversion will require more than one step."}, {"title": "Rate Determining Step and Rate Law Part 1.txt", "text": "Now let's look at the following complex reaction."}, {"title": "Rate Determining Step and Rate Law Part 1.txt", "text": "This is the overall reaction in which five molecules, two of these guys, one of this guy and two of these guys react to produce four moles of this guy and 1 mol of this guy."}, {"title": "Rate Determining Step and Rate Law Part 1.txt", "text": "So let's break this overall net reaction into its individual steps."}, {"title": "Rate Determining Step and Rate Law Part 1.txt", "text": "So step one is the following 1 mol of hydrogen peroxide reacts with 1 mol of this guy in a slow step producing 1 mol of hydroxide and 1 mol of hoi."}, {"title": "Rate Determining Step and Rate Law Part 1.txt", "text": "Now this slow step will be important in determining the rate law and we'll see in a second why."}, {"title": "Rate Determining Step and Rate Law Part 1.txt", "text": "Now the second step is the following."}, {"title": "Rate Determining Step and Rate Law Part 1.txt", "text": "This intermediate or this intermediate reacts with 1 mol reactants to produce again one molar hydroxide and one of our products."}, {"title": "Rate Determining Step and Rate Law Part 1.txt", "text": "Now notice that this is one of our products."}, {"title": "Rate Determining Step and Rate Law Part 1.txt", "text": "So step two is responsible for producing this product, namely this guy."}, {"title": "Rate Determining Step and Rate Law Part 1.txt", "text": "And now these two guys, two moles of hydroxide finally react with two moles of hydronium to produce our four moles of water, the second product."}, {"title": "Rate Determining Step and Rate Law Part 1.txt", "text": "So the second step is responsible for producing one of the products while the third step is responsible for producing the second type of product."}, {"title": "Rate Determining Step and Rate Law Part 1.txt", "text": "Now let's go back to this step."}, {"title": "Rate Determining Step and Rate Law Part 1.txt", "text": "Now, relative to the rates of these two steps, this is a very, very slow step and in fact these steps can be assumed to be instantaneous very quick."}, {"title": "Rate Determining Step and Rate Law Part 1.txt", "text": "So what's the significance of this slow step?"}, {"title": "Rate Determining Step and Rate Law Part 1.txt", "text": "This low step is called a rate determining step."}, {"title": "Rate Determining Step and Rate Law Part 1.txt", "text": "And this step limits the rate at which products are produced."}, {"title": "Rate Determining Step and Rate Law Part 1.txt", "text": "And this equation or this reaction can be used to find the rate law."}, {"title": "Rate Determining Step and Rate Law Part 1.txt", "text": "Now remember, the rate law can only really be found experimentally via results."}, {"title": "Rate Determining Step and Rate Law Part 1.txt", "text": "But this is a second way with which you can find the rate law."}, {"title": "Rate Determining Step and Rate Law Part 1.txt", "text": "But you still need to actually find the rate law using the results."}, {"title": "Rate Determining Step and Rate Law Part 1.txt", "text": "And then you can check the two and see if they coincide."}, {"title": "Rate Determining Step and Rate Law Part 1.txt", "text": "And usually for the most part they will coincide."}, {"title": "Rate Determining Step and Rate Law Part 1.txt", "text": "So this is a second way that you could find rate laws in complex reactions by using the rate law for the slow step, the rate determining step."}, {"title": "Rate Determining Step and Rate Law Part 1.txt", "text": "So since this is a bimolecular elementary reaction we can use the coefficients as the exponents."}, {"title": "Rate Determining Step and Rate Law Part 1.txt", "text": "In other words, our rate of reaction is equal to KR rate constant times the concentration of hydrogen peroxide times the concentration of iodine."}, {"title": "Rate Determining Step and Rate Law Part 1.txt", "text": "And each of the exponents is one because we have 1 mol of this guy and 1 mol of this guy react to produce these two intermediates."}, {"title": "Rate Determining Step and Rate Law Part 1.txt", "text": "And this is indeed a balanced equation."}, {"title": "Rate Determining Step and Rate Law Part 1.txt", "text": "So once again, the reason we're allowed to find a weight loss so quickly and without experimental results is because step one is an elementary bimolecular reaction with an overall reaction order of two."}, {"title": "Rate Determining Step and Rate Law Part 1.txt", "text": "In other words, this has one coefficient and a second coefficient."}, {"title": "Rate Determining Step and Rate Law Part 1.txt", "text": "So one plus one, two."}, {"title": "Rate Determining Step and Rate Law Part 1.txt", "text": "That's why."}, {"title": "Rate Determining Step and Rate Law Part 1.txt", "text": "Now, once again, once you find this guy, you have to check to make sure this is in fact the rate law."}, {"title": "Rate Determining Step and Rate Law Part 1.txt", "text": "By finding the rate law using experimental results for this bimolecular elementary reaction."}, {"title": "Octet Rule.txt", "text": "So in inorganic as well as organic chemistry, we're always concerned with the transfer of electrons."}, {"title": "Octet Rule.txt", "text": "So electrons are able to transfer from one atom to another atom."}, {"title": "Octet Rule.txt", "text": "So in this lecture, we're going to talk about the octave rule."}, {"title": "Octet Rule.txt", "text": "But before we talk about the octet rule, let's recall what the electron configuration of an atom atom is."}, {"title": "Octet Rule.txt", "text": "So let's look at helium, neon, and argon."}, {"title": "Octet Rule.txt", "text": "So the electron configuration is simply the layout of the electrons found within that atom."}, {"title": "Octet Rule.txt", "text": "So let's look at helium."}, {"title": "Octet Rule.txt", "text": "Now, helium has two protons found in the nucleus and two electrons."}, {"title": "Octet Rule.txt", "text": "These two electrons are going to be found in the one s orbital."}, {"title": "Octet Rule.txt", "text": "So the one s orbital can have a maximum of two electrons."}, {"title": "Octet Rule.txt", "text": "And because helium has two electrons, these two electrons will be found in the one s orbital."}, {"title": "Octet Rule.txt", "text": "So let's go to neon."}, {"title": "Octet Rule.txt", "text": "Now, neon has ten protons down in the nucleus and ten electrons down in the orbital surrounding our nucleus."}, {"title": "Octet Rule.txt", "text": "So our electron configuration for neon will be one f, two."}, {"title": "Octet Rule.txt", "text": "So two electrons will be in the one s orbital, two electrons will be in a two s orbital, and six electrons will be in the two p orbital."}, {"title": "Octet Rule.txt", "text": "Remember, there are actually three p orbitals."}, {"title": "Octet Rule.txt", "text": "There's PX, PY, and PZ."}, {"title": "Octet Rule.txt", "text": "And each orbital can hold a maximum of two electrons."}, {"title": "Octet Rule.txt", "text": "So that means we're going to have a total of six electrons in our p orbitals."}, {"title": "Octet Rule.txt", "text": "So, once again, our orbitals within neon are completely filled, just like they were in helium."}, {"title": "Octet Rule.txt", "text": "So let's look at argon."}, {"title": "Octet Rule.txt", "text": "Argon has 18 protons found in the nucleus, 18 electrons found in the surrounding orbital."}, {"title": "Octet Rule.txt", "text": "So we're going to have two electrons in the one s orbital, two electrons in the two s orbital, six electrons in the three p orbitals."}, {"title": "Octet Rule.txt", "text": "So a total of six in the p.\nNow we're going to have two electrons in the three s orbital, and three p will have six electrons."}, {"title": "Octet Rule.txt", "text": "So, once again, every orbital within our gun is completely filled, just like it was in neon and helium."}, {"title": "Octet Rule.txt", "text": "And in fact, these three atoms are noble gases."}, {"title": "Octet Rule.txt", "text": "Noble gases are atoms that have electron configurations that are completely filled."}, {"title": "Octet Rule.txt", "text": "So they have a perfect electron configuration."}, {"title": "Octet Rule.txt", "text": "All the orbitals that can possibly be filled are filled."}, {"title": "Octet Rule.txt", "text": "And that's exactly why noble gases are very stable."}, {"title": "Octet Rule.txt", "text": "They have very stable electron configurations."}, {"title": "Octet Rule.txt", "text": "And in fact, any atom that is not a noble gas will try to attain."}, {"title": "Octet Rule.txt", "text": "So it will try to either lose or gain electrons such that its electron configuration matches that of one of the noble gases."}, {"title": "Octet Rule.txt", "text": "And this is what we call the octave rule."}, {"title": "Octet Rule.txt", "text": "So the octave rule is simply the process of filling electron shells or electron orbitals in a way such that an electron configuration that matches one of the noble gases is reached."}, {"title": "Octet Rule.txt", "text": "So let's do an example."}, {"title": "Octet Rule.txt", "text": "So, here we have a carbon atom, and we have a fluorine atom."}, {"title": "Octet Rule.txt", "text": "So this carbon atom has six protons and six electrons."}, {"title": "Octet Rule.txt", "text": "So it has six protons within the nucleus along with the six neutrons."}, {"title": "Octet Rule.txt", "text": "And we have six electrons surrounding our nucleus."}, {"title": "Octet Rule.txt", "text": "So two electrons will be in the one s orbital, two electrons will be in the two s orbital, and only two electrons will be in the two p orbital."}, {"title": "Octet Rule.txt", "text": "So that means that there are four more electrons that can fit into our p orbitals because the p orbital can have a maximum of six electrons."}, {"title": "Octet Rule.txt", "text": "So if we go up here, that means that we want, or carbon wants to gain four more electrons so that its electron configuration matches that of neon."}, {"title": "Octet Rule.txt", "text": "So we basically want to attain this electron configuration."}, {"title": "Octet Rule.txt", "text": "Carbon wants to attain this electron configuration."}, {"title": "Octet Rule.txt", "text": "So that means that it is very likely that it will gain four electrons to form our perfect electron configuration."}, {"title": "Octet Rule.txt", "text": "So if this carbon had four electrons floating around this atom, that means it would gain those electrons, and these electrons would steal the remaining two p orbitals."}, {"title": "Octet Rule.txt", "text": "And that means once it gains the four electrons, it will have the one f two, two f two, and two p six the perfect configuration that matches neon."}, {"title": "Octet Rule.txt", "text": "So notice that a neutral atom of carbon has a charge of zero."}, {"title": "Octet Rule.txt", "text": "That's because it has six protons and six electrons."}, {"title": "Octet Rule.txt", "text": "Now, we have six protons."}, {"title": "Octet Rule.txt", "text": "By the way, this six, this subscript means six protons."}, {"title": "Octet Rule.txt", "text": "It's the atomic number which corresponds to the number of protons."}, {"title": "Octet Rule.txt", "text": "So we have six protons, but now we have four plus six electrons."}, {"title": "Octet Rule.txt", "text": "So we have a total of ten electrons, just like neon does."}, {"title": "Octet Rule.txt", "text": "And that means our charge will be negative ten plus six."}, {"title": "Octet Rule.txt", "text": "So our charge will be four."}, {"title": "Octet Rule.txt", "text": "So this is an anion."}, {"title": "Octet Rule.txt", "text": "So now let's look at Florida."}, {"title": "Octet Rule.txt", "text": "Now, fluorine has nine protons and nine electrons."}, {"title": "Octet Rule.txt", "text": "So once again, our nucleus will have nine protons, and our mutual fluorine atom will have nine electrons floating around the nucleus."}, {"title": "Octet Rule.txt", "text": "So once again, let's apply our octave rule and let's see how many electrons this fluorine atom, this neutral fluorine atom needs to gain to obtain a noble gas configuration."}, {"title": "Octet Rule.txt", "text": "So since nine is very close to ten, so this fluorine has nine electrons, which is only one away, one less than neon, that means fluorine will tend to gain an electron to form our neon noble gas configuration."}, {"title": "Octet Rule.txt", "text": "So, once again, if we have an electron floating around this fluorine nucleus, it will tend to take that electron and place it into one of the two p orbitals so that once it places it there, it has a noble gas configuration."}, {"title": "Octet Rule.txt", "text": "So, once again, this neutral fluorine atom gains one electron, puts it into the two p orbital, and it becomes an electron configuration that matches that of neon."}, {"title": "Octet Rule.txt", "text": "So it has two electrons in the one s. It has two electrons in the two s and six electrons in the two p. Now, this guy is very happy because he's very stable, and that's because noble gases have very stable electron configuration."}, {"title": "Octet Rule.txt", "text": "And that's basically what the Octave Rule is."}, {"title": "Octet Rule.txt", "text": "It's basically a procedure, a process that you follow that will give you a noble gas electron configuration."}, {"title": "Octet Rule.txt", "text": "So atoms such as nitrogen, such as carbon, fluorine and other halogens are able to undergo this Octave Rule or and gain electrons to form this perfect noble gas electron configuration."}, {"title": "Enthalpy, Heat of Reaction and Hess Law .txt", "text": "In this lecture, I will talk to you about the concept of enthalpy."}, {"title": "Enthalpy, Heat of Reaction and Hess Law .txt", "text": "Now, enthalpy is represented by the letter H or change in H. Enthalpy is a manmade concept or a manmade property that, unlike most other properties, like temperature, volume, and pressure, is not a measure of some intuitive property, which basically means means you can take an instrument and measure enthalpy, okay?"}, {"title": "Enthalpy, Heat of Reaction and Hess Law .txt", "text": "For example, I could take this water bottle, and I could measure the amount of water inside in terms of volume."}, {"title": "Enthalpy, Heat of Reaction and Hess Law .txt", "text": "I could measure the pressure."}, {"title": "Enthalpy, Heat of Reaction and Hess Law .txt", "text": "I could also measure the temperature."}, {"title": "Enthalpy, Heat of Reaction and Hess Law .txt", "text": "What I can say is, oh, this water bottle has x amount of enthalpy, okay?"}, {"title": "Enthalpy, Heat of Reaction and Hess Law .txt", "text": "And that's because enthalpy is defined using a formula."}, {"title": "Enthalpy, Heat of Reaction and Hess Law .txt", "text": "So when somebody asks you what enthalpy is, you tell them it's a formula."}, {"title": "Enthalpy, Heat of Reaction and Hess Law .txt", "text": "And the formula is this the change in enthalpy is equal to change in U plus P times change in B."}, {"title": "Enthalpy, Heat of Reaction and Hess Law .txt", "text": "So let's see what this guy is."}, {"title": "Enthalpy, Heat of Reaction and Hess Law .txt", "text": "This guy is just a total internal energy of the system, okay?"}, {"title": "Enthalpy, Heat of Reaction and Hess Law .txt", "text": "And if you look at this system here, which is a circle or a sphere, it's basically the collective energy of all the different molecules found within the system."}, {"title": "Enthalpy, Heat of Reaction and Hess Law .txt", "text": "So you sum their kinetic energies and you sum their potential energies, and that gives you, this guy here, the total infernal energy of the system."}, {"title": "Enthalpy, Heat of Reaction and Hess Law .txt", "text": "What this is is it's the work done to displace environment in creating the current state of the system, okay?"}, {"title": "Enthalpy, Heat of Reaction and Hess Law .txt", "text": "And what that basically means is in order to get from nothing to this volume and pressure, these molecules have to do work on the environment and displacing them in forming this structure, this sphere or the circle."}, {"title": "Enthalpy, Heat of Reaction and Hess Law .txt", "text": "So what enthalpy is, it's the total energy of the system plus the work that the system has to do on the environment in creating that system."}, {"title": "Enthalpy, Heat of Reaction and Hess Law .txt", "text": "And that's what enthalpy is."}, {"title": "Enthalpy, Heat of Reaction and Hess Law .txt", "text": "Now, enthalpy is a state function, which means that enthalpy is independent of the pathway and the reactions that lead to the system."}, {"title": "Enthalpy, Heat of Reaction and Hess Law .txt", "text": "In other words, enthalpy only depends on the current state of the system, okay?"}, {"title": "Enthalpy, Heat of Reaction and Hess Law .txt", "text": "Now, enthalpy is also an external property, which also means that entropy depends on the amount of the system."}, {"title": "Enthalpy, Heat of Reaction and Hess Law .txt", "text": "So the more of the system that we have, the largest system, the more enthalpy we have."}, {"title": "Enthalpy, Heat of Reaction and Hess Law .txt", "text": "And that's because enthalpy is related to internal energy, and internal energy is related to number of moles, number of particles."}, {"title": "Enthalpy, Heat of Reaction and Hess Law .txt", "text": "So the more particles we have, the more enthalpy we have."}, {"title": "Enthalpy, Heat of Reaction and Hess Law .txt", "text": "And that's why it's an external property."}, {"title": "Enthalpy, Heat of Reaction and Hess Law .txt", "text": "So because enthalpy is a man made concept, we can't talk about absolute values of enthalpy."}, {"title": "Enthalpy, Heat of Reaction and Hess Law .txt", "text": "They simply do not exist."}, {"title": "Enthalpy, Heat of Reaction and Hess Law .txt", "text": "What we do talk about are changes in enthalpy."}, {"title": "Enthalpy, Heat of Reaction and Hess Law .txt", "text": "And in order for changes in enthalpy to exist, we must assign zero values to Cherton atoms with the churchin's elements, okay?"}, {"title": "Enthalpy, Heat of Reaction and Hess Law .txt", "text": "And in fact, under a standard state of 1 bar or 750 tor and a certain temperature such as 25 degrees Celsius, all elements such as diatomic, hydrogen diatomic, oxygen, carbon diatonic, fluorine and so on are assigned a value of zero entropy, zero joules per mole."}, {"title": "Enthalpy, Heat of Reaction and Hess Law .txt", "text": "Okay?"}, {"title": "Enthalpy, Heat of Reaction and Hess Law .txt", "text": "So when a reaction or a compound is created from its constituents or from its raw elements, there's a change in entropy."}, {"title": "Enthalpy, Heat of Reaction and Hess Law .txt", "text": "And this change in entropy is known as the standard entropy of formation."}, {"title": "Enthalpy, Heat of Reaction and Hess Law .txt", "text": "And it's given this value where the small zero here called not is basically represents standard state or a 1 bar."}, {"title": "Enthalpy, Heat of Reaction and Hess Law .txt", "text": "Okay?"}, {"title": "Enthalpy, Heat of Reaction and Hess Law .txt", "text": "And this f is formation."}, {"title": "Enthalpy, Heat of Reaction and Hess Law .txt", "text": "So change in enthalpy, okay?"}, {"title": "Enthalpy, Heat of Reaction and Hess Law .txt", "text": "So standard enthalpy of formation and it basically means it's the change in enthalpy for a reaction that creates 1 mol of compound from its constituent elements."}, {"title": "Enthalpy, Heat of Reaction and Hess Law .txt", "text": "For example, let's take the creation or formation of water from its constituents, from hydrogen and from oxygen, okay?"}, {"title": "Enthalpy, Heat of Reaction and Hess Law .txt", "text": "These guys combine to form water and there is a decrease in enthalpy."}, {"title": "Enthalpy, Heat of Reaction and Hess Law .txt", "text": "And that means that the internal energy of the system decreases."}, {"title": "Enthalpy, Heat of Reaction and Hess Law .txt", "text": "There are less molecules within the system and so there is less Enthropy within the system."}, {"title": "Enthalpy, Heat of Reaction and Hess Law .txt", "text": "Now, different types of reactions exist."}, {"title": "Enthalpy, Heat of Reaction and Hess Law .txt", "text": "Some reactions are in a gas phase when other reactions are in a liquid and solid phases."}, {"title": "Enthalpy, Heat of Reaction and Hess Law .txt", "text": "Now, when you're dealing with reactions in a gas phase, you have to realize that gaseous systems are compressible."}, {"title": "Enthalpy, Heat of Reaction and Hess Law .txt", "text": "You can expand them and compress them."}, {"title": "Enthalpy, Heat of Reaction and Hess Law .txt", "text": "And so pressure changes because volume changes, so pressure isn't constant."}, {"title": "Enthalpy, Heat of Reaction and Hess Law .txt", "text": "And if pressure changes, if volume changes, then PV work is done."}, {"title": "Enthalpy, Heat of Reaction and Hess Law .txt", "text": "In other words, the system does work to expand by doing work in the surroundings, to move the surroundings away so that the system could expand."}, {"title": "Enthalpy, Heat of Reaction and Hess Law .txt", "text": "Same thing with compression."}, {"title": "Enthalpy, Heat of Reaction and Hess Law .txt", "text": "Therefore, when you're dealing with reactions of gases, this equation holds the change in enthalpy is equal to a change in internal energy plus p times change in volume."}, {"title": "Enthalpy, Heat of Reaction and Hess Law .txt", "text": "But when you're dealing with reactions in liquid and solid phases, you have to realize that these type of systems are not compressible."}, {"title": "Enthalpy, Heat of Reaction and Hess Law .txt", "text": "If you can't compress them or expand them, that means no PD work is done."}, {"title": "Enthalpy, Heat of Reaction and Hess Law .txt", "text": "Okay?"}, {"title": "Enthalpy, Heat of Reaction and Hess Law .txt", "text": "And that means this guy can go to zero."}, {"title": "Enthalpy, Heat of Reaction and Hess Law .txt", "text": "And now we could approximate the change in enthalpy to just simply change in internal energy, which is heat or the exchange of energy."}, {"title": "Enthalpy, Heat of Reaction and Hess Law .txt", "text": "Okay?"}, {"title": "Enthalpy, Heat of Reaction and Hess Law .txt", "text": "So under lab conditions, normally this condition holds."}, {"title": "Enthalpy, Heat of Reaction and Hess Law .txt", "text": "We could approximate this, we could approximate change in Enthalpy as just simply being the change in internal energy."}, {"title": "Enthalpy, Heat of Reaction and Hess Law .txt", "text": "So what is the heat of reaction?"}, {"title": "Enthalpy, Heat of Reaction and Hess Law .txt", "text": "The heat of reaction is simply the change in internal energy or change in enthalpy of the reaction."}, {"title": "Enthalpy, Heat of Reaction and Hess Law .txt", "text": "And it's found using this formula."}, {"title": "Enthalpy, Heat of Reaction and Hess Law .txt", "text": "For example, let's take this equation here we have reactants and we have products."}, {"title": "Enthalpy, Heat of Reaction and Hess Law .txt", "text": "To find the heat of reaction, we simply find a change in atrial energy or change in enthalpy of the product."}, {"title": "Enthalpy, Heat of Reaction and Hess Law .txt", "text": "We find the change in entropy or, I'm sorry, enthalpy of the reactants and we subtract this from this and that will give us the heat of reaction."}, {"title": "Enthalpy, Heat of Reaction and Hess Law .txt", "text": "So recall it, enthalpy is a state function and what that basically means that the pathway taken to get to the final product or to get to the final system does not affect the final change in enthalpy."}, {"title": "Enthalpy, Heat of Reaction and Hess Law .txt", "text": "And this jumps directly into something called Hess's Law."}, {"title": "Enthalpy, Heat of Reaction and Hess Law .txt", "text": "Now, Hessa's Law basically states that the steps taken to get from the reactant to the products does not affect the final change in enthalpy, okay?"}, {"title": "Enthalpy, Heat of Reaction and Hess Law .txt", "text": "And Hess's Law can be applied to reactions."}, {"title": "Enthalpy, Heat of Reaction and Hess Law .txt", "text": "Now, here we have an imaginary reaction."}, {"title": "Enthalpy, Heat of Reaction and Hess Law .txt", "text": "That's a two step reaction."}, {"title": "Enthalpy, Heat of Reaction and Hess Law .txt", "text": "And each step has its corresponding change in enthalpy."}, {"title": "Enthalpy, Heat of Reaction and Hess Law .txt", "text": "Now, what Hess Law basically states is that in order to find the final change in enthalpy, you simply add each corresponding enthalpy."}, {"title": "Enthalpy, Heat of Reaction and Hess Law .txt", "text": "Together we get the final result."}, {"title": "Enthalpy, Heat of Reaction and Hess Law .txt", "text": "So ten kilojoules per mole plus 20 kilojoules per mole gives you 30 kilojoules per mole."}, {"title": "Enthalpy, Heat of Reaction and Hess Law .txt", "text": "And this is their final answer."}, {"title": "Enthalpy, Heat of Reaction and Hess Law .txt", "text": "Now, yield this side, you basically the same exact thing."}, {"title": "Enthalpy, Heat of Reaction and Hess Law .txt", "text": "You use basic algebra."}, {"title": "Enthalpy, Heat of Reaction and Hess Law .txt", "text": "You add these guys up."}, {"title": "Enthalpy, Heat of Reaction and Hess Law .txt", "text": "You add these guys up, except instead of using equal sign like you would use in algebra, you use arrows."}, {"title": "Enthalpy, Heat of Reaction and Hess Law .txt", "text": "Okay?"}, {"title": "Enthalpy, Heat of Reaction and Hess Law .txt", "text": "So A plus B plus B plus C gives you a plus two b plus C arrows."}, {"title": "Enthalpy, Heat of Reaction and Hess Law .txt", "text": "C plus D. Now, one last thing left."}, {"title": "Enthalpy, Heat of Reaction and Hess Law .txt", "text": "You have to notice the molecules that appear on both sides of the equation."}, {"title": "Enthalpy, Heat of Reaction and Hess Law .txt", "text": "If they appear on both sides of the equation, you could simply cross them out, okay?"}, {"title": "Enthalpy, Heat of Reaction and Hess Law .txt", "text": "So A appears only on this side, you leave it alone."}, {"title": "Enthalpy, Heat of Reaction and Hess Law .txt", "text": "Two B appears only on this side, you leave it alone."}, {"title": "Enthalpy, Heat of Reaction and Hess Law .txt", "text": "C appears on this side, and on this side, you cross them out."}, {"title": "Enthalpy, Heat of Reaction and Hess Law .txt", "text": "And D appears only on this side."}, {"title": "Enthalpy, Heat of Reaction and Hess Law .txt", "text": "So you leave it alone."}, {"title": "Enthalpy, Heat of Reaction and Hess Law .txt", "text": "And this makes sense, because what He's Law states is that only the reactants and products count."}, {"title": "Enthalpy, Heat of Reaction and Hess Law .txt", "text": "The inter immediate steps will do nothing, okay?"}, {"title": "Enthalpy, Heat of Reaction and Hess Law .txt", "text": "Because enthalpy is a state function."}, {"title": "pH indicators .txt", "text": "In this lecture we're going to talk a bit more about titrations and equivalence points."}, {"title": "pH indicators .txt", "text": "Now, earlier in another video, we saw that we can actually calculate our equivalence point using a formula."}, {"title": "pH indicators .txt", "text": "Now, if you want to learn more about that, check out the link above."}, {"title": "pH indicators .txt", "text": "Now, actually calculating your equivalence point isn't very useful when you're conducting your experiment."}, {"title": "pH indicators .txt", "text": "When you're titrating, you want to actually visualize the equivalence point."}, {"title": "pH indicators .txt", "text": "And to visualize it, you use two things."}, {"title": "pH indicators .txt", "text": "The first thing you use is a PH meter."}, {"title": "pH indicators .txt", "text": "The PH meter will automatically tell you the PH of your solution."}, {"title": "pH indicators .txt", "text": "For example, suppose this is your PH meter and it's attached to your solution at any given time, you can look at it and it will tell you the PH of your buffer solution."}, {"title": "pH indicators .txt", "text": "Now, the second thing you need to use is called an acid based indicator."}, {"title": "pH indicators .txt", "text": "Acid based indicators are compounds that change color in solution when they convert to their conjugate acid based form."}, {"title": "pH indicators .txt", "text": "Now, what you do is you take your indicator, you take a very small amount of it and you place it into your solution before you begin saturation."}, {"title": "pH indicators .txt", "text": "And what the indicator does, it reacts with the H plus ions in the following way."}, {"title": "pH indicators .txt", "text": "When there is a lot of H plus ions associated in our solution, aka, when it's acidic, that means equilibrium will shift this way."}, {"title": "pH indicators .txt", "text": "Now, when there is very little H plus ions or our concentration of H plus ion is very low, equilibrium will shift this way."}, {"title": "pH indicators .txt", "text": "Meaning we're going to have more of the conjugate base of our conjugate acid."}, {"title": "pH indicators .txt", "text": "Note that this represents one color and this represents a different color."}, {"title": "pH indicators .txt", "text": "So in solution, when this guy predominates, our solution will be of this color."}, {"title": "pH indicators .txt", "text": "And when this guy is now a solution and this guy predominates, the solution B will be of a different color."}, {"title": "pH indicators .txt", "text": "So once again, in acidic solutions, this guy dominates."}, {"title": "pH indicators .txt", "text": "And in basic solutions, this guy dominates."}, {"title": "pH indicators .txt", "text": "So, we can look at the ratio of the concentration of this guy to this guy."}, {"title": "pH indicators .txt", "text": "And when the ratio is ten or above, that means we're going to be of this guy, of this color, so of the active color, because there's much more of this than this in our solution."}, {"title": "pH indicators .txt", "text": "Now, the opposite is true as well."}, {"title": "pH indicators .txt", "text": "When this guy will dominate, when there is more of this guy than this guy."}, {"title": "pH indicators .txt", "text": "Now, ratio is 0.1 or less."}, {"title": "pH indicators .txt", "text": "That means the base color will dominate."}, {"title": "pH indicators .txt", "text": "So this guy will dominate."}, {"title": "pH indicators .txt", "text": "Now, note that the end point is the point at which you observe a change in color."}, {"title": "pH indicators .txt", "text": "And the end point is not the same thing as the equivalence point."}, {"title": "pH indicators .txt", "text": "There are two different things."}, {"title": "titration.txt", "text": "In this lecture we're going to look at something called titration."}, {"title": "titration.txt", "text": "Now, titration is a process by which one slowly adds an acid to a base or a base to an acid with the purpose of determining the concentration of our unknown sample of solution."}, {"title": "titration.txt", "text": "Now, whatever we're adding to our unknown sample, it's called a titren, and a titrate be their base or an acid."}, {"title": "titration.txt", "text": "So let's illustrate Titration using a picture and then a graph."}, {"title": "titration.txt", "text": "So suppose we have some known volume of acid, say, I don't know, hydrochloric acid in our flask, and we have a PH reader attached to the inside of our flask."}, {"title": "titration.txt", "text": "So at any given time, we could measure our PH."}, {"title": "titration.txt", "text": "Now suppose we have some known concentration of base and we begin adding this base drop by drop."}, {"title": "titration.txt", "text": "Now, before we add the base, our PH is say, I don't know, two."}, {"title": "titration.txt", "text": "Okay, that's our PH."}, {"title": "titration.txt", "text": "Now, as I begin slowly adding drop by drop, what will happen to our PH?"}, {"title": "titration.txt", "text": "Well, it will increase."}, {"title": "titration.txt", "text": "Right, but how will it increase?"}, {"title": "titration.txt", "text": "Well, let's look at the graph of PH versus volume added, where PH is the Y axis, and volume added of our base in this case is the x axis."}, {"title": "titration.txt", "text": "So according to this graph, we see that the relationship is based on a sigmoidal curve."}, {"title": "titration.txt", "text": "And what that means is that initially, when you first add some known amount of concentration of base, the PH change will be very little."}, {"title": "titration.txt", "text": "The PH won't change by that much."}, {"title": "titration.txt", "text": "And in fact, from this much to this much volume added, the PH only rises by maybe 0.5."}, {"title": "titration.txt", "text": "But eventually we come to a point where any more volume added will increase the PH dramatically."}, {"title": "titration.txt", "text": "And we will come to a point where the PH will increase by ten units."}, {"title": "titration.txt", "text": "So why is that?"}, {"title": "titration.txt", "text": "Well, let's see."}, {"title": "titration.txt", "text": "Now let's look at the reaction of sodium hydroxide with hydrochloric acid."}, {"title": "titration.txt", "text": "Initially, we only have HCL in our mixture and HCL dissociates into H plus ion and the chloride ion."}, {"title": "titration.txt", "text": "Now, the H plus ion is what's responsible for creating the acidic solution for lowering our PH to a PH of two."}, {"title": "titration.txt", "text": "So what will happen when we first dissociate or add NaOH to our mixture?"}, {"title": "titration.txt", "text": "Well, initially we only have a small amount of NaOH, and NaOH will dissociate into Ma plus and oh minus."}, {"title": "titration.txt", "text": "But since we only have a small amount of NaOH, that means we only have a small amount of these guys."}, {"title": "titration.txt", "text": "And these guys are the ones that associate with HMCL to form water and NaCl."}, {"title": "titration.txt", "text": "So initially, only a small percentage of these guys will reassociate into this form."}, {"title": "titration.txt", "text": "And so we will see a decrease in the H plus ion, but a very small decrease."}, {"title": "titration.txt", "text": "And that means we're only going to see a very small change or increase in PH initially."}, {"title": "titration.txt", "text": "What will happen when the ratio of moles is one to one?"}, {"title": "titration.txt", "text": "So suppose we have some ratio of HCL, some unknown in our solution and suppose we add that same amount of moles, of NaOH."}, {"title": "titration.txt", "text": "Well, that means we're going to have a ratio one to one to one to one."}, {"title": "titration.txt", "text": "And all these guys are going to reassociate to form water and NaCl."}, {"title": "titration.txt", "text": "And what will happen then?"}, {"title": "titration.txt", "text": "Well, then our PH will become seven, right?"}, {"title": "titration.txt", "text": "And in fact, at this point, when the ratio of moles added is the same as the ratio of this guy, this point is called the equivalence point."}, {"title": "titration.txt", "text": "And for NaOH and HCL, for a strong acid and strong base, this is a PH of seven."}, {"title": "titration.txt", "text": "So we see that this point is the point at which we add enough Maoh that our ratio begins to equal out."}, {"title": "titration.txt", "text": "Our ratio becomes closer and closer to one and one."}, {"title": "titration.txt", "text": "And as we add more, as we get closer to a ratio of one to one, we get closer to our PH of seven."}, {"title": "titration.txt", "text": "And that's why we see this large increase in PH."}, {"title": "titration.txt", "text": "Now, if we begin to add more of our sodium hydroxide, our solution becomes basic."}, {"title": "titration.txt", "text": "And that's because all the acid has been neutralized."}, {"title": "titration.txt", "text": "And by adding more of this guy, we simply increase the concentration of oh."}, {"title": "titration.txt", "text": "And so our solution will become basic."}, {"title": "Introduction to PV work.txt", "text": "Recall what the conservation of energy tells us."}, {"title": "Introduction to PV work.txt", "text": "According to the conservation of energy, energy cannot be destroyed and it cannot be created."}, {"title": "Introduction to PV work.txt", "text": "Energy always exists, and energy of the Universe is constant."}, {"title": "Introduction to PV work.txt", "text": "It does not change."}, {"title": "Introduction to PV work.txt", "text": "But what energy can do is it can be transformed from one form to another."}, {"title": "Introduction to PV work.txt", "text": "For example, from kinetic energy to another."}, {"title": "Introduction to PV work.txt", "text": "Another type of energy."}, {"title": "Introduction to PV work.txt", "text": "Now there are two types of energy transfers."}, {"title": "Introduction to PV work.txt", "text": "There's heat and work."}, {"title": "Introduction to PV work.txt", "text": "Heat is a natural Transfer of energy from an object with a Higher temperature to an object with a Lower temperature."}, {"title": "Introduction to PV work.txt", "text": "And if you want to learn more about heat, check out the lecture on heat in the chemistry section."}, {"title": "Introduction to PV work.txt", "text": "Here."}, {"title": "Introduction to PV work.txt", "text": "We're only going to talk about work."}, {"title": "Introduction to PV work.txt", "text": "Now work is the transfer of energy due to forces."}, {"title": "Introduction to PV work.txt", "text": "It could be individual forces acting on objects or the net forces acting on the entire object."}, {"title": "Introduction to PV work.txt", "text": "Now, work is a scalar, and that means it only has magnitude, no direction."}, {"title": "Introduction to PV work.txt", "text": "And the units of work is like the units of energy."}, {"title": "Introduction to PV work.txt", "text": "It's joules."}, {"title": "Introduction to PV work.txt", "text": "And we could also use electron volts when we're talking about very small microscopic objects."}, {"title": "Introduction to PV work.txt", "text": "Now."}, {"title": "Introduction to PV work.txt", "text": "Work does have negative and a positive."}, {"title": "Introduction to PV work.txt", "text": "Negative work simply means our object loses energy, while positive work means our object gains energy."}, {"title": "Introduction to PV work.txt", "text": "Now, whenever a nonfictional force is applied, work can be found using the following equation work is equal to the force applied on our object, times the distance our object moves."}, {"title": "Introduction to PV work.txt", "text": "And since work is, in fact a scalar, a vector times a vector gives us a dot product."}, {"title": "Introduction to PV work.txt", "text": "So that means we take the cosine of the angle."}, {"title": "Introduction to PV work.txt", "text": "If you want to learn more about dot product and cross product, check out the lecture on that."}, {"title": "Introduction to PV work.txt", "text": "So, basically, if we have some object, say, this block, and we apply a force with an angle theta to the horizontal of that object, and our object moves a distance d we can find the amount of work done on the object."}, {"title": "Introduction to PV work.txt", "text": "The amount of energy that object gain by using the following formula force times, distance travel times, cosine of the angle between them."}, {"title": "Introduction to PV work.txt", "text": "Now, if we do not neglect friction, if we actually include friction, for example, when this box is traveling along this horizontal surface, there is friction in a real world situation."}, {"title": "Introduction to PV work.txt", "text": "So if we do not neglect friction, we find our overall work by following the following formula the work done is equal to change in our potential energy of the object plus change in the kinetic energy of the object plus the change in the internal energy of our object due to friction."}, {"title": "Introduction to PV work.txt", "text": "Now, for the most part, whenever friction acts on an object, it changes the object's internal energy."}, {"title": "Introduction to PV work.txt", "text": "And internal energy is simply the energy of the individual molecules found in that object."}, {"title": "Introduction to PV work.txt", "text": "If you sum up all the different types of energies on those individual molecules, you will get the internal energy of that system."}, {"title": "Introduction to PV work.txt", "text": "Now, if we end up neglecting friction, if we don't include friction, for example, we say this surface on which our object is traveling is frictionless."}, {"title": "Introduction to PV work.txt", "text": "We have to use the following formula to find out total work done."}, {"title": "Introduction to PV work.txt", "text": "The work is equal to change in our potential energy of the object, plus change in the kinetic energy of that object."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "So in this lecture we're going to look at three examples of redox reactions."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "And we're going to assign oxidation states to each atom in our molecule."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "So let's begin with the first one."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "So we begin with copper in its elemental state."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "And that means copper gets a charge of zero according to our rules."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "Let's look at nitric acid."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "Now, nitric acid, it contains an hmm and an O."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "That means we first assign to H, then we assign to O, then we assign to the N. Now our entire molecule must be neutral, so we must take that into consideration when assigning."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "So let's give our H a plus one according to our table."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "And let's give an O a minus two according to our table."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "So our N should be a number, such that when you add that number to one and when you subtract negative six, we get here."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "Why negative six?"}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "Well, because there are three oxygen molecules."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "So three times negative two gives us a total of negative six."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "So negative six plus one gives us a five."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "So our N should be five."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "Let's check."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "One plus five."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "Six minus six gives us a zero."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "So that works."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "Let's go to this side."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "So here we have copper nitrate."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "So from this part we know that N and three is a negative one, right, because the entire thing to balance a neutral charge, this must be a plus one."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "So this guy is minus one."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "So our three is minus one."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "So no three is minus one times two such molecules, this whole thing means it's negative two."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "So our copper must be plus two."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "Our copper is plus two."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "Now that means our oxygen is negative two, and our N must be plus five."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "So this whole thing must be minus two, including this two here."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "So let's go to nitric oxide."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "So our O, we first assign our oxidation state to O, and our O gets a minus two."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "So that means our N must be plus two."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "Why is it plus two?"}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "Well, because this molecule is neutral and that means charge of zero."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "So to balance this negative two, this N must be a plus two."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "And finally, let's look at water the oxygen."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "Well, we first assign to our H. So that gets a plus one."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "Plus one times two gives us a plus two."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "So this guy must be a negative two to balance out the mutual charge."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "So now let's look at what gets oxidized and what gets reduced."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "So our copper goes from a zero charge to a plus two charge."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "And that means copper is oxidized because electrons are removed and these electrons transfer to some other atom."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "So let's look at what atom is reduced."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "So our N goes from a plus five to a plus two."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "That means all the electrons move from copper to N, creating that plus two charge."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "So our N is what's reduced."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "So our oxidizing agent is this guy nitric acid, the N specifically."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "And our reducing agent is copper."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "So let's write that."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "So this guy is oxidized and this guy is reduced."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "And once again, our reducing agent, our oxidizing agent."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "So let's move on to example two."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "Now, in example two, we begin with the copper sulfide."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "So an oxygen in its elemental state."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "So oxygen automatically gets a charge of zero because it's in its elemental state."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "And let's look at these guys."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "First, we assign our charge to our sulfur."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "Now, sulfur is in the same group as oxygen."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "That means it gets a negative two charge."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "So our sulfur is negative two."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "Now, to balance this guy off, because this entire molecule is neutral charge of zero, our copper must be a plus one because we have two copper molecules."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "So plus one, let's check two times one, two minus 20 works."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "So we're done with our reactant side."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "Let's go to product side."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "So now copper is in our elemental state."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "So our copper must be neutral zero."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "And let's look at so, oxygen gets assigned first."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "So oxygen gets a negative two."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "A negative two times two is negative four."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "So what must s be?"}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "Well, if this whole thing is neutral, this guy must be plus four."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "Why?"}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "Well, because plus four minus four negative two times two gives us zero."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "So let's see what's reduced and what's oxidized."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "Our oxygen goes from zero to negative two."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "And that means this guy is reduced."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "So let's write this."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "So it's reduced."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "Our oxygen is reduced."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "So what gets oxidized?"}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "If something is reduced, something must be oxidized."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "So our copper goes from a plus one to zero."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "And that means, actually, copper also gets reduced."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "And so copper is actually also reduced."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "So let's write reduced for our copper."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "Now, sulfur goes from negative two to positive four."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "That means our sulfur is the atom that gets oxidized."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "So let's write that."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "So this guy gets oxidized."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "So two atoms get reduced, one atom gets oxidized."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "So this guy, that means this guy's our reducing agent."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "While our oxygen must be the oxidizing agent because it obtains those electrons."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "It takes those electrons away from the sulfur atom."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "So let's look at our final example."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "So zinc sulfide plus oxygen gives us this guy."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "So our oxygen once again is in its elemental state."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "So our oxygen gets a charge of zero, a neutral charge."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "Let's look at these guys."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "So, we assign our charge to sulfur first."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "So sulfur gets a charge of negative two because it's in the same group as oxygen."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "So this guy gets a negative two."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "And our zinc must have a charge of plus two."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "So plus two minus two gives us neutral."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "Makes sense."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "Let's go to this guy."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "So first we assign our charge to oxygen."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "Oxygen gets a charge of negative two."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "So this guy gets a charge of negative two."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "Now our zinc stays at positive two."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "So zinc remains at positive two."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "So in order for this whole molecule to be to have a charge of zero, that means all these guys must add up to zero."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "So negative two times eight times four gives us negative eight."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "Plus two gives us negative six."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "Sulfur must have a positive six charge."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "So what's oxidized?"}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "What's reduced?"}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "Well, our oxygen goes from zero to negative two."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "So that means oxygen gets reduced."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "Okay?"}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "Now, our sulfur goes from negative two to plus six."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "And that means our sulfur gets oxidized."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "So our sulfur gets oxidized."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "So whatever gets reduced is the oxidizing agent because it takes electrons away from that atom, specifically, the S atom."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "So this is our oxidizing agent."}, {"title": "Oxidation-Reduction Reactions Example .txt", "text": "And this guy, that reducing agent."}, {"title": "Solutions and Solvation.txt", "text": "In this lecture, I will talk to you about solutions."}, {"title": "Solutions and Solvation.txt", "text": "So, what are solutions?"}, {"title": "Solutions and Solvation.txt", "text": "Solutions are simply mixtures of two more compounds found in the same state."}, {"title": "Solutions and Solvation.txt", "text": "They're also called homogeneous solutions."}, {"title": "Solutions and Solvation.txt", "text": "Homogeneous simply means in the same state."}, {"title": "Solutions and Solvation.txt", "text": "Now, since there are three states possible, three types of solutions exist solid solutions, liquid solutions and gas solutions."}, {"title": "Solutions and Solvation.txt", "text": "An example of a solid solution is brass."}, {"title": "Solutions and Solvation.txt", "text": "Brass is a metal composed of zinc and copper."}, {"title": "Solutions and Solvation.txt", "text": "An example of a liquid solution is sodium chloride or salt, found in water."}, {"title": "Solutions and Solvation.txt", "text": "An example of a gas solution is air."}, {"title": "Solutions and Solvation.txt", "text": "Air is composed of nitrogen and oxygen."}, {"title": "Solutions and Solvation.txt", "text": "Now, whenever we talk about solutions, it's important to differentiate between the solvent and a solute."}, {"title": "Solutions and Solvation.txt", "text": "The solvent is a compound of which there is more."}, {"title": "Solutions and Solvation.txt", "text": "And the solute is a compound of which there is less."}, {"title": "Solutions and Solvation.txt", "text": "So let's go back to our examples in brass, brass is composed of 55% copper and 45% zinc."}, {"title": "Solutions and Solvation.txt", "text": "So there's more copper, which means copper is a solvent and zinc is a solute."}, {"title": "Solutions and Solvation.txt", "text": "In this example, there's more water than sodium, chloride or salt."}, {"title": "Solutions and Solvation.txt", "text": "So the solvent is water and the solute is the salt."}, {"title": "Solutions and Solvation.txt", "text": "Now let's go to our gas example."}, {"title": "Solutions and Solvation.txt", "text": "In our gas solution, there's 79% nitrogen."}, {"title": "Solutions and Solvation.txt", "text": "So this guy is a solvent and 21% oxygen."}, {"title": "Solutions and Solvation.txt", "text": "So oxygen is a solve."}, {"title": "Solutions and Solvation.txt", "text": "Now let's look at ideal dilute solutions."}, {"title": "Solutions and Solvation.txt", "text": "So what are ideal dilute solutions?"}, {"title": "Solutions and Solvation.txt", "text": "These solutions are simply solutions in which every single sole molecule is separated by a solvent molecule."}, {"title": "Solutions and Solvation.txt", "text": "So there is no interaction between neighboring soluble molecules."}, {"title": "Solutions and Solvation.txt", "text": "Let's look at an example."}, {"title": "Solutions and Solvation.txt", "text": "So this is an example of an ideal dilute solution."}, {"title": "Solutions and Solvation.txt", "text": "In this example, the sodium and a chloride are separated by water molecules so they can't interact."}, {"title": "Solutions and Solvation.txt", "text": "This is an example of a nonideal dilute solution."}, {"title": "Solutions and Solvation.txt", "text": "In this example, the sodium and the chloride are able to interact with each other, so therefore, it's non."}, {"title": "Solutions and Solvation.txt", "text": "Ideal dissolving is a process by which solvent molecules break apart solvent molecules from one another."}, {"title": "Solutions and Solvation.txt", "text": "Now, in the solvent, there's water."}, {"title": "Solutions and Solvation.txt", "text": "This is called hydration."}, {"title": "Solutions and Solvation.txt", "text": "Now remember, light dissolves like so."}, {"title": "Solutions and Solvation.txt", "text": "Polar molecules dissolve polar molecules and nonpolar molecules will dissolve other nonpolar molecules."}, {"title": "Solutions and Solvation.txt", "text": "Nonpolar will not be able to dissolve polar, and that's because they won't be able to overcome the large dipole moments of the polar molecules."}, {"title": "Solutions and Solvation.txt", "text": "And these dipole moments come from large differences in electronegativity."}, {"title": "Solutions and Solvation.txt", "text": "Now, salvation is the process of breaking down ionic compounds, bipolar compounds such as H 20."}, {"title": "Solutions and Solvation.txt", "text": "Now, the results are aqueous solutions."}, {"title": "Solutions and Solvation.txt", "text": "Within an aqueous solution, the ions are able to move freely, so that electrons are also able to move freely."}, {"title": "Solutions and Solvation.txt", "text": "And because, because of this, aqueous solutions conduct electricity very well."}, {"title": "Solutions and Solvation.txt", "text": "So water will not be able to conduct electricity as well as a solution of sodium, chloride and water."}, {"title": "Rate Determining Step and Rate Law Part 2.txt", "text": "In the previous lecture we began our discussion on complex reactions and I showed you how to obtain the rate law for a complex reaction in which the first step was the slow step or the rate determining step."}, {"title": "Rate Determining Step and Rate Law Part 2.txt", "text": "Now we're going to look at complex shifts in which the first step is the fastest and the second step is the slow step or the rate determining step."}, {"title": "Rate Determining Step and Rate Law Part 2.txt", "text": "So let's look at the following complex reaction in which two no molecules react with one BR two molecule to produce two moles of Nobr molecules."}, {"title": "Rate Determining Step and Rate Law Part 2.txt", "text": "Now from experimental results we find that our rate law is k times concentration of no squared times the concentration of BR two squared."}, {"title": "Rate Determining Step and Rate Law Part 2.txt", "text": "Now this guy comes from experiment and our goal in this lecture will be to find the rate law using the second step, the slow step and compare that rate law to our experimental rate law and see if they coincide."}, {"title": "Rate Determining Step and Rate Law Part 2.txt", "text": "So first let's examine that situation at hand."}, {"title": "Rate Determining Step and Rate Law Part 2.txt", "text": "Notice our first step is now the fast step and that means 1 mol of N o will react with 1 mol of BR two to produce 1 mol of no BR two."}, {"title": "Rate Determining Step and Rate Law Part 2.txt", "text": "And this step will be really quick meaning that by the time it gets here it's going to go back."}, {"title": "Rate Determining Step and Rate Law Part 2.txt", "text": "And in fact we're going to assume that this step, this reaction first reaction is at equilibrium before this reaction even begins."}, {"title": "Rate Determining Step and Rate Law Part 2.txt", "text": "And we're going to assume that the concentration of this guy is very, very small."}, {"title": "Rate Determining Step and Rate Law Part 2.txt", "text": "Now let's look at the second step."}, {"title": "Rate Determining Step and Rate Law Part 2.txt", "text": "In the second step, notice that the reactant, this guy is the intermediate, this guy."}, {"title": "Rate Determining Step and Rate Law Part 2.txt", "text": "So the product of step one is the reaction of step two and that means step two will be dependent on step one and that's because the intermediate is part of the reactive part of the slow step process."}, {"title": "Rate Determining Step and Rate Law Part 2.txt", "text": "So the slow step is still the rate determining step and we're still going to use this step to find our rate law."}, {"title": "Rate Determining Step and Rate Law Part 2.txt", "text": "But now we're going to have to take this guide into consideration from the first step."}, {"title": "Rate Determining Step and Rate Law Part 2.txt", "text": "So let's write the rate determining or let's write the rate law for our first step."}, {"title": "Rate Determining Step and Rate Law Part 2.txt", "text": "So remember, we're dealing with an elementary bimolecular reaction, the first step as well as a second step."}, {"title": "Rate Determining Step and Rate Law Part 2.txt", "text": "So we can write our rate laws in the following manner."}, {"title": "Rate Determining Step and Rate Law Part 2.txt", "text": "The rate of the first step is equal to k one."}, {"title": "Rate Determining Step and Rate Law Part 2.txt", "text": "Our constant going this way times the concentration of this guy to the first power because we have a coefficient of one times the concentration of BR also to the first power because we have a coefficient of 1 mol."}, {"title": "Rate Determining Step and Rate Law Part 2.txt", "text": "Now this equals to the reverse reaction because we're assuming our equilibrium or the first reaction reached equilibrium."}, {"title": "Rate Determining Step and Rate Law Part 2.txt", "text": "And so this rate equals this rate, the reverse rate."}, {"title": "Rate Determining Step and Rate Law Part 2.txt", "text": "So this guy equals the constant minus one going this way times the concentration of this guy."}, {"title": "Rate Determining Step and Rate Law Part 2.txt", "text": "Now when we go backwards this is already active."}, {"title": "Rate Determining Step and Rate Law Part 2.txt", "text": "So these guys are equal."}, {"title": "Rate Determining Step and Rate Law Part 2.txt", "text": "All right, now we're done."}, {"title": "Rate Determining Step and Rate Law Part 2.txt", "text": "Let's write the rate law for our second step to slow step."}, {"title": "Rate Determining Step and Rate Law Part 2.txt", "text": "So rate is equal to k two or some constant for going this way times the concentration of Nobr two times the concentration of no."}, {"title": "Rate Determining Step and Rate Law Part 2.txt", "text": "Now, notice that this guy appears here and here."}, {"title": "Rate Determining Step and Rate Law Part 2.txt", "text": "Therefore, we can represent this guy in terms of all these guys."}, {"title": "Rate Determining Step and Rate Law Part 2.txt", "text": "So let's bring the k negative one over and we get the following."}, {"title": "Rate Determining Step and Rate Law Part 2.txt", "text": "Nobr or the concentration of Nobr equals k one divided by k minus one, right times no or concentration of no times the concentration of BR two."}, {"title": "Rate Determining Step and Rate Law Part 2.txt", "text": "And now we want to take this whole guy and plug it into our rate law for our step number two."}, {"title": "Rate Determining Step and Rate Law Part 2.txt", "text": "For our slow step, we plug this guy in and we get the following our rate for the second step, the slow step is equal to k two."}, {"title": "Rate Determining Step and Rate Law Part 2.txt", "text": "This guy times k one."}, {"title": "Rate Determining Step and Rate Law Part 2.txt", "text": "This guy divided by k minus one."}, {"title": "Rate Determining Step and Rate Law Part 2.txt", "text": "This guy times two of these because one comes from the second step and one comes from the first step times this guy."}, {"title": "Rate Determining Step and Rate Law Part 2.txt", "text": "The concentration of BR two from the first step gives you this."}, {"title": "Rate Determining Step and Rate Law Part 2.txt", "text": "Now we can combine these to give exponent of two."}, {"title": "Rate Determining Step and Rate Law Part 2.txt", "text": "And we can let this guy be some other constants, say KC."}, {"title": "Rate Determining Step and Rate Law Part 2.txt", "text": "And so our rate becomes KC times the concentration of NL squared times the concentration of BR."}, {"title": "Rate Determining Step and Rate Law Part 2.txt", "text": "And this is exactly what we get from experiments some constant k which we can say they're equal times the concentration of this guy squared times the concentration of BR two."}, {"title": "Rate Determining Step and Rate Law Part 2.txt", "text": "This is exactly what we get from experiments."}, {"title": "Rate Determining Step and Rate Law Part 2.txt", "text": "And so our rate laws do coincide."}, {"title": "Rate Determining Step and Rate Law Part 2.txt", "text": "Now, once again, whenever our rate law is not the first step, it's the second or third step."}, {"title": "Rate Determining Step and Rate Law Part 2.txt", "text": "We have to take into consideration the intermediate guys because the intermediate guys will determine the concentration of reactants for the slow step."}, {"title": "Rate Determining Step and Rate Law Part 2.txt", "text": "And that's why they need to be taken into consideration."}, {"title": "Rate Determining Step and Rate Law Part 2.txt", "text": "So what we basically did is first we found the rate law for our first reaction, for our fast reaction for going the forward and going backwards."}, {"title": "Rate Determining Step and Rate Law Part 2.txt", "text": "And then we found the rate law for the second reaction going one way because it's the slow step."}, {"title": "Rate Determining Step and Rate Law Part 2.txt", "text": "And then we basically represent the intermediate concentration as everything else."}, {"title": "Rate Determining Step and Rate Law Part 2.txt", "text": "And we plug that in into our equation and we found our final rate law."}, {"title": "Determining pH of Strong and Weak Acids and Bases .txt", "text": "So let's look at both methods."}, {"title": "Determining pH of Strong and Weak Acids and Bases .txt", "text": "Now, first we'll do the quadratic formula."}, {"title": "Determining pH of Strong and Weak Acids and Bases .txt", "text": "So let ka be 1.8\ntimes ten to negative five."}, {"title": "Determining pH of Strong and Weak Acids and Bases .txt", "text": "You can look that up in a textbook."}, {"title": "Determining pH of Strong and Weak Acids and Bases .txt", "text": "So we get 1.8\ntimes ten to negative five gives you X times X divided by 0.02 minus X, that gives you X squared divided by 0.2 minus X."}, {"title": "Determining pH of Strong and Weak Acids and Bases .txt", "text": "Now we bring this guy over on this side, and we get 1.8 times ten to negative five multiplied by 0.2 minus X gives you X squared."}, {"title": "Determining pH of Strong and Weak Acids and Bases .txt", "text": "Now distribute, and we get 1.8 times ten to negative five multiplied by 0.2 minus this guy multiplied by X gives you 1.8\ntimes ten to negative five."}, {"title": "Determining pH of Strong and Weak Acids and Bases .txt", "text": "X equals X squared."}, {"title": "Determining pH of Strong and Weak Acids and Bases .txt", "text": "Now we bring everything to one side, and we equate it to zero."}, {"title": "Determining pH of Strong and Weak Acids and Bases .txt", "text": "So we want a positive X squared, because it's easier to work with."}, {"title": "Determining pH of Strong and Weak Acids and Bases .txt", "text": "So we bring these guys over on this side."}, {"title": "Determining pH of Strong and Weak Acids and Bases .txt", "text": "So X squared plus 1.8\ntimes ten to the negative five."}, {"title": "Determining pH of Strong and Weak Acids and Bases .txt", "text": "Because when we bring this guy over, this becomes a positive minus, because this guy was initially a plus."}, {"title": "Determining pH of Strong and Weak Acids and Bases .txt", "text": "So when we bring it over, it will be a -3.6\ntimes ten to the negative seven equals zero."}, {"title": "Determining pH of Strong and Weak Acids and Bases .txt", "text": "Now we use a quadratic formula which states negative B squared plus minus square root of B squared minus four AC divided by two A."}, {"title": "Determining pH of Strong and Weak Acids and Bases .txt", "text": "So in our case, our A is one."}, {"title": "Determining pH of Strong and Weak Acids and Bases .txt", "text": "Our b is this guy?"}, {"title": "Determining pH of Strong and Weak Acids and Bases .txt", "text": "1.8 times tens, negative five."}, {"title": "Determining pH of Strong and Weak Acids and Bases .txt", "text": "And our C is negative 3.6\ntimes ten to the negative seven."}, {"title": "Determining pH of Strong and Weak Acids and Bases .txt", "text": "So let's plug everything in."}, {"title": "Determining pH of Strong and Weak Acids and Bases .txt", "text": "We get negative 1.8\ntimes 10th to negative five squared plus minus a square root of 1.8 times ten to negative five squared minus four times one times A times C times this guy."}, {"title": "Determining pH of Strong and Weak Acids and Bases .txt", "text": "So divided by two."}, {"title": "Determining pH of Strong and Weak Acids and Bases .txt", "text": "So now we simplify these guys, and we get negative 3.24 times ten to negative ten plus minus 0012 divided by two."}, {"title": "Determining pH of Strong and Weak Acids and Bases .txt", "text": "Now we get two answers."}, {"title": "Determining pH of Strong and Weak Acids and Bases .txt", "text": "One is negative."}, {"title": "Determining pH of Strong and Weak Acids and Bases .txt", "text": "One is positive."}, {"title": "Determining pH of Strong and Weak Acids and Bases .txt", "text": "Remember, we're dealing with concentrations."}, {"title": "Determining pH of Strong and Weak Acids and Bases .txt", "text": "That means concentrations can't be negative."}, {"title": "Determining pH of Strong and Weak Acids and Bases .txt", "text": "So we reject this negative one, and we accept this guy, which is 6.7 times ten to negative seven."}, {"title": "Determining pH of Strong and Weak Acids and Bases .txt", "text": "So our initial concentration of our acetic acid was 0.02."}, {"title": "Determining pH of Strong and Weak Acids and Bases .txt", "text": "Our final concentration is 0.02 minus this guy gives you 0.0194."}, {"title": "Determining pH of Strong and Weak Acids and Bases .txt", "text": "So they're very close, only a little bit dissociated."}, {"title": "Determining pH of Strong and Weak Acids and Bases .txt", "text": "And that makes sense because this acetic acid is a very weak acid."}, {"title": "Determining pH of Strong and Weak Acids and Bases .txt", "text": "Its ka is very small."}, {"title": "Determining pH of Strong and Weak Acids and Bases .txt", "text": "So that was the first way, first method of finding our concentration."}, {"title": "Determining pH of Strong and Weak Acids and Bases .txt", "text": "What's the second way?"}, {"title": "Determining pH of Strong and Weak Acids and Bases .txt", "text": "Well, the second way is a much better way, but it is an approximation."}, {"title": "Determining pH of Strong and Weak Acids and Bases .txt", "text": "So if you are allowed to approximate, you should definitely use this way, because it's shorter."}, {"title": "Determining pH of Strong and Weak Acids and Bases .txt", "text": "Now, let me show you what happens."}, {"title": "Determining pH of Strong and Weak Acids and Bases .txt", "text": "So let's go back to our first step."}, {"title": "Determining pH of Strong and Weak Acids and Bases .txt", "text": "So 1.8\ntimes ten to negative five equals X squared divided by 0.2 minus X."}, {"title": "Determining pH of Strong and Weak Acids and Bases .txt", "text": "Now, remember, our initial concentration is 0.2."}, {"title": "Determining pH of Strong and Weak Acids and Bases .txt", "text": "And our final concentration is very small."}, {"title": "Determining pH of Strong and Weak Acids and Bases .txt", "text": "It's very small compared to our initial."}, {"title": "Determining pH of Strong and Weak Acids and Bases .txt", "text": "That's because we have a very weak acid, not a lot of the acid will dissociate."}, {"title": "Determining pH of Strong and Weak Acids and Bases .txt", "text": "And so our final concentration, our X, will be much smaller than 0.2, our initial concentration."}, {"title": "Determining pH of Strong and Weak Acids and Bases .txt", "text": "So we can approximate this guy to be equal to X squared over 0.2\nbecause our concentration will change by that much because we see, look, 0.94 and 0.2 and only changed by 0.6."}, {"title": "Determining pH of Strong and Weak Acids and Bases .txt", "text": "That's a very small amount."}, {"title": "Determining pH of Strong and Weak Acids and Bases .txt", "text": "So now we have this very simple situation in which we simply bring over the 0.2, multiply it by 1.8\ntimes ten to negative five equals X squared."}, {"title": "Determining pH of Strong and Weak Acids and Bases .txt", "text": "Take the radical, and we get 1.8 times ten to negative five times zero."}, {"title": "Determining pH of Strong and Weak Acids and Bases .txt", "text": "Two radical gives you two answers a positive and a negative."}, {"title": "Determining pH of Strong and Weak Acids and Bases .txt", "text": "We reject the negative because concentrations can't be negative and we take the positive guy."}, {"title": "Determining pH of Strong and Weak Acids and Bases .txt", "text": "Now look how close this guy is to this guy."}, {"title": "Determining pH of Strong and Weak Acids and Bases .txt", "text": "There's a difference of only zero."}, {"title": "Determining pH of Strong and Weak Acids and Bases .txt", "text": "That's a very small difference between our approximation, our shorter method, and our exact value, the longer method."}, {"title": "Determining pH of Strong and Weak Acids and Bases .txt", "text": "So if you're allowed to approximate, you should definitely use this method."}, {"title": "Determining pH of Strong and Weak Acids and Bases .txt", "text": "But if you need the exact answer, you should definitely use the first method."}, {"title": "Structural Conformations and Newman Projections .txt", "text": "In this lecture we're going to discuss structural conformations as well as mum projections."}, {"title": "Structural Conformations and Newman Projections .txt", "text": "Now, we're going to use the ethane molecule as an example."}, {"title": "Structural Conformations and Newman Projections .txt", "text": "Ethane is a two carbon alkane."}, {"title": "Structural Conformations and Newman Projections .txt", "text": "So it's composed of two carbons and six H atoms."}, {"title": "Structural Conformations and Newman Projections .txt", "text": "Now, let's begin by examining the three dimensional picture of our ethane molecule."}, {"title": "Structural Conformations and Newman Projections .txt", "text": "So ethane looks something like this, where these two black intersections are our carbons."}, {"title": "Structural Conformations and Newman Projections .txt", "text": "So carbon one and carbon two given by these two carbons on the board."}, {"title": "Structural Conformations and Newman Projections .txt", "text": "Now, these rest spheres are our H atoms."}, {"title": "Structural Conformations and Newman Projections .txt", "text": "So we have six altogether."}, {"title": "Structural Conformations and Newman Projections .txt", "text": "Now, these black solid wedges are our Sigma bonds, the Covalent bonds coming out of the board given by these two bonds here."}, {"title": "Structural Conformations and Newman Projections .txt", "text": "These dashed wedges are given by these two bonds, sigma bonds in the back."}, {"title": "Structural Conformations and Newman Projections .txt", "text": "They're going into the board."}, {"title": "Structural Conformations and Newman Projections .txt", "text": "These two sigma bonds are on the plane of the page, on the plane of the board."}, {"title": "Structural Conformations and Newman Projections .txt", "text": "So if this was the XY axis, that means these two sigma bonds would be on the plane, on the XY plane."}, {"title": "Structural Conformations and Newman Projections .txt", "text": "Now, one thing you should know about coding single sigma bonds is that these bonds are able to rotate in space."}, {"title": "Structural Conformations and Newman Projections .txt", "text": "They could rotate 360 degrees around."}, {"title": "Structural Conformations and Newman Projections .txt", "text": "So since all these guides are sigma bonds, all of these bonds are able to rotate."}, {"title": "Structural Conformations and Newman Projections .txt", "text": "And in fact, what confirmations are there are three dimensional structures related to one another by sigma bond rotations."}, {"title": "Structural Conformations and Newman Projections .txt", "text": "For example, here I have one confirmation."}, {"title": "Structural Conformations and Newman Projections .txt", "text": "If I rotate this bond some given amount of degrees, I will have a second type of confirmation."}, {"title": "Structural Conformations and Newman Projections .txt", "text": "So these two molecules are related to one another by the fact that they're rotated some amount of degrees about this carbon carbon bond."}, {"title": "Structural Conformations and Newman Projections .txt", "text": "And these guys are also known as confirmers."}, {"title": "Structural Conformations and Newman Projections .txt", "text": "Now, there are many different types of conference that exist, right?"}, {"title": "Structural Conformations and Newman Projections .txt", "text": "There's one conference, a second conference, a third conference, a fourth conference, and so on."}, {"title": "Structural Conformations and Newman Projections .txt", "text": "Two important conference that you should know are the Eclipse conference and the staggered confirmer."}, {"title": "Structural Conformations and Newman Projections .txt", "text": "Now, Eclipsed simply means that these two ch bonds are eclipsed."}, {"title": "Structural Conformations and Newman Projections .txt", "text": "They're on the same plane."}, {"title": "Structural Conformations and Newman Projections .txt", "text": "So if we look this way on our molecule, so here is our molecule and we're looking this way, we're going to see that this carbon bond, this carbon H bond exactly aligns with this carbon H bond."}, {"title": "Structural Conformations and Newman Projections .txt", "text": "And likewise this carbon H bond aligns with this and this carbon H bond aligns with, aligns with this one."}, {"title": "Structural Conformations and Newman Projections .txt", "text": "Now this is eclipse."}, {"title": "Structural Conformations and Newman Projections .txt", "text": "What happens if we take the sigma bond and we rotate the sigma bond 180 degrees in this fashion?"}, {"title": "Structural Conformations and Newman Projections .txt", "text": "So we rotated 180 degrees."}, {"title": "Structural Conformations and Newman Projections .txt", "text": "Well, we get the following staggered confirmation."}, {"title": "Structural Conformations and Newman Projections .txt", "text": "Staggered simply means that this sigma bond, carbon, carbon sigma bond rotate 180 degrees."}, {"title": "Structural Conformations and Newman Projections .txt", "text": "And so these angles are now a 60 degree angle to one another."}, {"title": "Structural Conformations and Newman Projections .txt", "text": "So before we had zero degrees between each, between each carbon H bond."}, {"title": "Structural Conformations and Newman Projections .txt", "text": "But now we have a measure of 60 degrees between this bond and this bond."}, {"title": "Structural Conformations and Newman Projections .txt", "text": "Now this is a more stable confirmation and we'll see why in a second."}, {"title": "Structural Conformations and Newman Projections .txt", "text": "So now let's talk about Newman projections."}, {"title": "Structural Conformations and Newman Projections .txt", "text": "Now, Newman projections are simply a way to visualize these three dimensional structures on a two dimensional plane, like this whiteboard or a sheet of paper."}, {"title": "Structural Conformations and Newman Projections .txt", "text": "So once again, let's take our eclipse three dimensional structure and let's look at the structure from this way down."}, {"title": "Structural Conformations and Newman Projections .txt", "text": "So when you look at it this way, in an eclipsed fashion, in an eclipse confirmation, all these ch bonds are aligned exactly across one another."}, {"title": "Structural Conformations and Newman Projections .txt", "text": "So if we look this way down, all we'll see is this carbon bond and these three ch bonds."}, {"title": "Structural Conformations and Newman Projections .txt", "text": "Because this ch bond, for example, will exactly cancel out the one in the back."}, {"title": "Structural Conformations and Newman Projections .txt", "text": "And the same thing goes for these other two."}, {"title": "Structural Conformations and Newman Projections .txt", "text": "So that means looking this way, this is exactly what we see."}, {"title": "Structural Conformations and Newman Projections .txt", "text": "Well, this is not a very good presentation because we can see the carbon, the back, we can't see the three ch bonds in the back."}, {"title": "Structural Conformations and Newman Projections .txt", "text": "They do exist, but we can't really see them."}, {"title": "Structural Conformations and Newman Projections .txt", "text": "And that's exactly where newer projections come in."}, {"title": "Structural Conformations and Newman Projections .txt", "text": "It simply gives us a better way of visualizing this three dimensional structure."}, {"title": "Structural Conformations and Newman Projections .txt", "text": "And it's given by the following depiction."}, {"title": "Structural Conformations and Newman Projections .txt", "text": "So we simply take three ch bonds and we connect them like so, where each bond here is 120 degrees."}, {"title": "Structural Conformations and Newman Projections .txt", "text": "Now, this intersection in the middle represents our first carbon atom."}, {"title": "Structural Conformations and Newman Projections .txt", "text": "Now, to visualize the back carbon atom, we simply draw this blue circle, which symbolizes this blue carbon here."}, {"title": "Structural Conformations and Newman Projections .txt", "text": "And then, because these ch bonds are right across on the same plane of these ch bonds, we simply shift them slightly this way so that we can visualize it."}, {"title": "Structural Conformations and Newman Projections .txt", "text": "Now, you should know these ch bonds in the back are actually aligned exactly with this ch bond."}, {"title": "Structural Conformations and Newman Projections .txt", "text": "And the same goes for these two."}, {"title": "Structural Conformations and Newman Projections .txt", "text": "But in order for us to visualize it, we shift the angle."}, {"title": "Structural Conformations and Newman Projections .txt", "text": "We cheat a little bit."}, {"title": "Structural Conformations and Newman Projections .txt", "text": "We shift the angle so that we can actually see them."}, {"title": "Structural Conformations and Newman Projections .txt", "text": "So our carbon one, our carbon two and the ch bonds in the back, like we have here now."}, {"title": "Structural Conformations and Newman Projections .txt", "text": "Or for the standard confirmation, it gets a little bit easier."}, {"title": "Structural Conformations and Newman Projections .txt", "text": "Because if we look at the staggered confirmation, which looks like this, what we see is this picture here."}, {"title": "Structural Conformations and Newman Projections .txt", "text": "So we have the carbon atom and it's attached to three ch bonds."}, {"title": "Structural Conformations and Newman Projections .txt", "text": "So three HS."}, {"title": "Structural Conformations and Newman Projections .txt", "text": "And then we have that bad carbon that's also attached to these three ch bonds."}, {"title": "Structural Conformations and Newman Projections .txt", "text": "So in this picture, we can't really see the carbon atom."}, {"title": "Structural Conformations and Newman Projections .txt", "text": "So that's exactly why we want the human projection."}, {"title": "Structural Conformations and Newman Projections .txt", "text": "In the human projection, we can visualize this back carbon blue atom that's given here, as well as this first carbon atom."}, {"title": "Structural Conformations and Newman Projections .txt", "text": "Green one here, given by this intersection."}, {"title": "Structural Conformations and Newman Projections .txt", "text": "So the angle between any two bonds here is 60 degrees, as we said earlier for the staggered."}, {"title": "Structural Conformations and Newman Projections .txt", "text": "So the angle here between any two ch bonds is zero."}, {"title": "Structural Conformations and Newman Projections .txt", "text": "The angle here is 60 degrees."}, {"title": "Structural Conformations and Newman Projections .txt", "text": "And the angle between any two of these bonds, for example, this green ch bond."}, {"title": "Structural Conformations and Newman Projections .txt", "text": "And this green ch bond is 120 20 degrees."}, {"title": "Isomers of Heptane.txt", "text": "So, in this lecture, I'd like to find all the possible isomers of the heptane molecule, a seven carbon alkane."}, {"title": "Isomers of Heptane.txt", "text": "So let's begin by defining what an isomer is."}, {"title": "Isomers of Heptane.txt", "text": "So, isomers are compounds that have the same molecular formula but different structures."}, {"title": "Isomers of Heptane.txt", "text": "So whenever we try to find isomers of alkanes, it usually helps to have a systematic approach, and that's exactly what we use in this example."}, {"title": "Isomers of Heptane.txt", "text": "Here, we have a set of four steps that we're going to follow to find our isomers."}, {"title": "Isomers of Heptane.txt", "text": "And, in fact, we can always use these same steps whenever we're trying to find isomers of alkanes."}, {"title": "Isomers of Heptane.txt", "text": "So let's begin with step one."}, {"title": "Isomers of Heptane.txt", "text": "Now, step one happens to be the easiest one, and you'll see why in just a second."}, {"title": "Isomers of Heptane.txt", "text": "Begin with the longest carbon chain."}, {"title": "Isomers of Heptane.txt", "text": "So what's the longest carbon chain of our heptane molecule?"}, {"title": "Isomers of Heptane.txt", "text": "Well, it's simply heptane itself."}, {"title": "Isomers of Heptane.txt", "text": "So in step one, our first isomer is heptane itself."}, {"title": "Isomers of Heptane.txt", "text": "So here we have our heptane, and this is our first isomer."}, {"title": "Isomers of Heptane.txt", "text": "Let's go to step two."}, {"title": "Isomers of Heptane.txt", "text": "So, in step two, shorten the chain by removing exactly one carbon from the end of our chain."}, {"title": "Isomers of Heptane.txt", "text": "So we remove this carbon, and then we place that carbon onto a different position."}, {"title": "Isomers of Heptane.txt", "text": "So let's remove it."}, {"title": "Isomers of Heptane.txt", "text": "And now let's take that methyl group and place it onto the first position or the second position here."}, {"title": "Isomers of Heptane.txt", "text": "Now, if we place it onto this position, we get back our heptane."}, {"title": "Isomers of Heptane.txt", "text": "The goal is to develop as many structural different compounds as possible."}, {"title": "Isomers of Heptane.txt", "text": "So here's one more isomer."}, {"title": "Isomers of Heptane.txt", "text": "Notice that these two guys have the same exact molecular formula, but they have different structural forms."}, {"title": "Isomers of Heptane.txt", "text": "So now let's take this methyl and place it onto this carbon, and we will get another isomer."}, {"title": "Isomers of Heptane.txt", "text": "So we place this methyl group here, and we get a third isomer."}, {"title": "Isomers of Heptane.txt", "text": "And notice if we draw one more guy, and then we place our methyl onto this position."}, {"title": "Isomers of Heptane.txt", "text": "This guy is exactly the same as this guy."}, {"title": "Isomers of Heptane.txt", "text": "And so this is not an isomer, because these two guys have the same molecular formula and the same structural forms."}, {"title": "Isomers of Heptane.txt", "text": "So this is not an isomer."}, {"title": "Isomers of Heptane.txt", "text": "So let's remove this guy."}, {"title": "Isomers of Heptane.txt", "text": "So, it looks like we're done with step two."}, {"title": "Isomers of Heptane.txt", "text": "Let's go to step three."}, {"title": "Isomers of Heptane.txt", "text": "So, in step three, it says shorten the chain by removing two carbons."}, {"title": "Isomers of Heptane.txt", "text": "Not one, but two."}, {"title": "Isomers of Heptane.txt", "text": "So now we're removing this carbon as well as this carbon."}, {"title": "Isomers of Heptane.txt", "text": "So we're developing a pentane molecule, and now we have two carbon atoms at our disposal, methyl groups at our disposal."}, {"title": "Isomers of Heptane.txt", "text": "So let's first point the two methyl groups here."}, {"title": "Isomers of Heptane.txt", "text": "That's one isomer."}, {"title": "Isomers of Heptane.txt", "text": "Let's show our pentane again."}, {"title": "Isomers of Heptane.txt", "text": "And now take one methyl, place it here."}, {"title": "Isomers of Heptane.txt", "text": "The second methyl."}, {"title": "Isomers of Heptane.txt", "text": "Place it here."}, {"title": "Isomers of Heptane.txt", "text": "That's a second isomer."}, {"title": "Isomers of Heptane.txt", "text": "Let's show one more pentane."}, {"title": "Isomers of Heptane.txt", "text": "And let's leave this methyl here and place this methyl here."}, {"title": "Isomers of Heptane.txt", "text": "That's yet another isomer."}, {"title": "Isomers of Heptane.txt", "text": "So let's see if we can get more isomers."}, {"title": "Isomers of Heptane.txt", "text": "Let's actually take both of these guys and place them here."}, {"title": "Isomers of Heptane.txt", "text": "And let's take one more."}, {"title": "Isomers of Heptane.txt", "text": "And place it like so all these guys have different structures, but identical molecular formulas, so they're all isomers."}, {"title": "Isomers of Heptane.txt", "text": "So let's go to step four, because we're essentially done here, if we rearrange them in some other way, we're going to get back on the same molecule as before."}, {"title": "Isomers of Heptane.txt", "text": "So let's go to step four."}, {"title": "Isomers of Heptane.txt", "text": "In step four, I have dot, dot, dot, because we're simply removing not one or two, but three carbons from the end."}, {"title": "Isomers of Heptane.txt", "text": "So we're moving one, two, three."}, {"title": "Isomers of Heptane.txt", "text": "So here we have one."}, {"title": "Isomers of Heptane.txt", "text": "So we have one, two, three."}, {"title": "Isomers of Heptane.txt", "text": "And now we have three carbons at our disposal, three methyl groups."}, {"title": "Isomers of Heptane.txt", "text": "So let's place one here, a second one here, and let's place a third one here."}, {"title": "Isomers of Heptane.txt", "text": "And this concludes our isomers."}, {"title": "Isomers of Heptane.txt", "text": "We should have a total of nine, so 123-45-6789."}, {"title": "Isomers of Heptane.txt", "text": "So once again, these steps work for any alkanes."}, {"title": "Isomers of Heptane.txt", "text": "Whenever you're trying to find the isomers of alkanes, you follow these steps."}, {"title": "Isomers of Heptane.txt", "text": "You begin with the longest possible carbon chain, and then you keep removing a carbon atom, a methyl group, and reattaching it, forming our new isomers."}, {"title": "Electrochemical cell .txt", "text": "Now, in this lecture, we're going to talk about something called electrochemical cells, also known as Galvanic cells."}, {"title": "Electrochemical cell .txt", "text": "Now, recall that redox reactions are chemical reactions in which electrons flow from one atom to another."}, {"title": "Electrochemical cell .txt", "text": "From physics, we know that moving charge such as electrons can be used to do useful work."}, {"title": "Electrochemical cell .txt", "text": "Therefore, the flow of electrons found in redox reactions can somehow be transformed to do useful work."}, {"title": "Electrochemical cell .txt", "text": "So an electrochemical cell is simply a way to capture this useful work produced by the movement of electrons from one atom to another."}, {"title": "Electrochemical cell .txt", "text": "Now, we're going to talk about special types of electrochemical cells called voltaic cells, also known as batteries."}, {"title": "Electrochemical cell .txt", "text": "Now, these types of cells contain oxidizing reducing agent pairs connected by a conductor such as a wire."}, {"title": "Electrochemical cell .txt", "text": "And this conductor allows electrons to flow from one atom to a second atom."}, {"title": "Electrochemical cell .txt", "text": "Now, let's look at a layout of a voltaic cell."}, {"title": "Electrochemical cell .txt", "text": "Voltaic cells broken down into two half cells."}, {"title": "Electrochemical cell .txt", "text": "So one half cell in a second half cell."}, {"title": "Electrochemical cell .txt", "text": "In the first half cell, one half reaction takes place called oxidation."}, {"title": "Electrochemical cell .txt", "text": "And the second half reaction takes place in a second half cell called reduction."}, {"title": "Electrochemical cell .txt", "text": "Now, this wire connects the two cells."}, {"title": "Electrochemical cell .txt", "text": "This wire is our conductor allowing electrons to flow."}, {"title": "Electrochemical cell .txt", "text": "This is a light bulb that lights up when there is a flow of electrons."}, {"title": "Electrochemical cell .txt", "text": "And this salt bridge becomes important in allowing these electrons to continually flow."}, {"title": "Electrochemical cell .txt", "text": "Now, let's look at this picture in more detail and let's see exactly what voltaic cells are and how they function."}, {"title": "Electrochemical cell .txt", "text": "So let's examine the following reduction reaction."}, {"title": "Electrochemical cell .txt", "text": "So, zinc solid reacts with aqueous copper to form a crease zinc and solid copper."}, {"title": "Electrochemical cell .txt", "text": "Notice that our zinc solid is oxidized."}, {"title": "Electrochemical cell .txt", "text": "It loses two electrons to form a plus two ana while those two same electrons are taken up by our copper molecule in the Aqueous state."}, {"title": "Electrochemical cell .txt", "text": "And so this guy is reduced from a plus two to a neutral atom."}, {"title": "Electrochemical cell .txt", "text": "Now, oxidation of zinc occurs in half cell number one."}, {"title": "Electrochemical cell .txt", "text": "And zinc solid becomes zinc in the Aqueous state with a plus two charge, and it releases two electrons while in half cell number two reduction occurs."}, {"title": "Electrochemical cell .txt", "text": "An aqueous copper takes up two electrons to form solid copper."}, {"title": "Electrochemical cell .txt", "text": "So let's examine these reactions as they occur within our electrochemical cell, our voltaic cell."}, {"title": "Electrochemical cell .txt", "text": "So in eco number one and half cell number one, this red bar corresponds to our zinc solid."}, {"title": "Electrochemical cell .txt", "text": "So zinc solid releases two electrons and it also releases our zinc ion."}, {"title": "Electrochemical cell .txt", "text": "Now, this zinc ion is released into our solution from our metal bar."}, {"title": "Electrochemical cell .txt", "text": "So the solution that has water as solvent increases in its concentration of zinc ion and at the same time, it increases the positive charge found within our solution in beaker one in half cell number one."}, {"title": "Electrochemical cell .txt", "text": "Now, these electrons travel through the conductor and across and into the other side."}, {"title": "Electrochemical cell .txt", "text": "Now, as it travels from this side to this side, this light bulb lights up."}, {"title": "Electrochemical cell .txt", "text": "And therefore, this light bulb allows us to visualize the movement of these electrons."}, {"title": "Electrochemical cell .txt", "text": "As soon as it lights up, we know that electrons are traveling from this side to this side."}, {"title": "Electrochemical cell .txt", "text": "Now let's look at hop cell number two."}, {"title": "Electrochemical cell .txt", "text": "So this metal bar corresponds to our copper solid."}, {"title": "Electrochemical cell .txt", "text": "And what happens is these two electrons combine with this copper ions down within the aqueous solution to form our copper solid."}, {"title": "Electrochemical cell .txt", "text": "So in this solution, the copper ions move from in the solution to inside this metal bar."}, {"title": "Electrochemical cell .txt", "text": "So our concentration of copper ions found in solution decreases."}, {"title": "Electrochemical cell .txt", "text": "And that means our plus charge found in this solution also decreases."}, {"title": "Electrochemical cell .txt", "text": "So now let's look at a few terms that we need to know."}, {"title": "Electrochemical cell .txt", "text": "Electrodes are metals that conduct electrical current into out of the solution."}, {"title": "Electrochemical cell .txt", "text": "So in this case, this is our electrode and this is our electrode."}, {"title": "Electrochemical cell .txt", "text": "So our zinc solid and copper solid are our electrodes because they're metals that allow electrons to flow in or out."}, {"title": "Electrochemical cell .txt", "text": "So the anode is defined to be the half cell where oxidation takes place."}, {"title": "Electrochemical cell .txt", "text": "So the anode is this guy."}, {"title": "Electrochemical cell .txt", "text": "It includes beaker one, the aqueous solution, as well as the electrode."}, {"title": "Electrochemical cell .txt", "text": "Beaker one, the capital, is defined to be the half cell where reduction takes place."}, {"title": "Electrochemical cell .txt", "text": "So this is our cathode."}, {"title": "Electrochemical cell .txt", "text": "It includes the aqueous solution, the beaker, as well as the electrode down and beaker two."}, {"title": "Electrochemical cell .txt", "text": "So electrons travel from our anode to our cathode."}, {"title": "Electrochemical cell .txt", "text": "Now let's look at the salt bridge."}, {"title": "Electrochemical cell .txt", "text": "We still have discussed what this guy here is."}, {"title": "Electrochemical cell .txt", "text": "This is our salt bridge."}, {"title": "Electrochemical cell .txt", "text": "Now, our salt bridge is composed of a solution of salt."}, {"title": "Electrochemical cell .txt", "text": "For example, k two, so four."}, {"title": "Electrochemical cell .txt", "text": "So what's the purpose?"}, {"title": "Electrochemical cell .txt", "text": "What's the function of our salt bridge?"}, {"title": "Electrochemical cell .txt", "text": "Well, let's look at this picture here."}, {"title": "Electrochemical cell .txt", "text": "Eventually, when enough electrons travel to this location, what will happen to our positive charge in this speaker and our positive charge in this speaker?"}, {"title": "Electrochemical cell .txt", "text": "Well, we're going to have a build up, a positive charge in this speaker because this metal bar releases ions, right while in this speaker, these ions found within our solution are taken up by this metal bar, meaning there's a decrease in positive charge found on this side."}, {"title": "Electrochemical cell .txt", "text": "So eventually, if we don't have anything connecting them like a salt bridge, the electrons will stop flowing."}, {"title": "Electrochemical cell .txt", "text": "So in order for the electrons to continue to flow, the circuit, this circuit must be closed."}, {"title": "Electrochemical cell .txt", "text": "And it's closed using this sold bridge."}, {"title": "Electrochemical cell .txt", "text": "And what happens is this salt dissociates into k plus."}, {"title": "Electrochemical cell .txt", "text": "And so for minus ions, and the positively charged ions begin to flow into the second half cell into the cathode."}, {"title": "Electrochemical cell .txt", "text": "And this increases the positive charge found in this cathode in this half cell two."}, {"title": "Electrochemical cell .txt", "text": "Now, the same happens with the so minus four."}, {"title": "Electrochemical cell .txt", "text": "This guy begins to travel this way, decreasing the positive charge found in the amode in half cell number one allows the electrons to continually flow."}, {"title": "The Periodic Table .txt", "text": "In this lecture we're going to talk about the periodic table of elements."}, {"title": "The Periodic Table .txt", "text": "Now there are over 100 different types of elements or atoms found on Earth."}, {"title": "The Periodic Table .txt", "text": "That means we need a very good way of organizing all these elements."}, {"title": "The Periodic Table .txt", "text": "And the periodic table does just that."}, {"title": "The Periodic Table .txt", "text": "What it does is it organizes our elements or atoms into columns and rows."}, {"title": "The Periodic Table .txt", "text": "Now the columns are known as groups or families, while the rows are called periods."}, {"title": "The Periodic Table .txt", "text": "So let's zoom in on our periodic table."}, {"title": "The Periodic Table .txt", "text": "So this is a general representation of our periodic table."}, {"title": "The Periodic Table .txt", "text": "I did not include the names of our atoms and I also did not include other elements usually found in two rows on the bottom."}, {"title": "The Periodic Table .txt", "text": "Now that's simply for simplification purposes."}, {"title": "The Periodic Table .txt", "text": "If you'd like to see the actual table, Google it or check out a chemistry textbook."}, {"title": "The Periodic Table .txt", "text": "Now these guys, these columns are known as groups."}, {"title": "The Periodic Table .txt", "text": "So group one, group two, group three, group four, all the way up to group 18, while these rows are known as periods."}, {"title": "The Periodic Table .txt", "text": "So period one, period two, period 3456, all the way up to period seven."}, {"title": "The Periodic Table .txt", "text": "Now these guys, or this table is divided into three main divisions known as metals, nonmetals and metalloids."}, {"title": "The Periodic Table .txt", "text": "Now the white squares or the white elements are known as metals."}, {"title": "The Periodic Table .txt", "text": "And they're found from left all the way up to this section here."}, {"title": "The Periodic Table .txt", "text": "Now the orange guys are known as metalloids, while the red guys are known as nonmetals."}, {"title": "The Periodic Table .txt", "text": "Now group 18 is called the Noble gas group, while group 17, the group right next to group 18, are known as halogens."}, {"title": "The Periodic Table .txt", "text": "Now these guys here from this group to group number three are called transition metals."}, {"title": "The Periodic Table .txt", "text": "Group number one are known as alkaline metals, and group number two are known as alkaline earth metals."}, {"title": "The Periodic Table .txt", "text": "Now we're going to go into more detail in our next lecture about what the alkaline, alkaline, earth, noble halogens and transition metals are."}, {"title": "The Periodic Table .txt", "text": "In this lecture, we're only going to look at the three divisions that exist, namely metals, metalloids and nonmetals."}, {"title": "The Periodic Table .txt", "text": "So let's zoom out."}, {"title": "The Periodic Table .txt", "text": "Now."}, {"title": "The Periodic Table .txt", "text": "Let's examine our divisions."}, {"title": "The Periodic Table .txt", "text": "Let's look at the metals."}, {"title": "The Periodic Table .txt", "text": "Metals are large atoms that tend to lose electrons with great ease, forming ions in which the oxidation state is positive."}, {"title": "The Periodic Table .txt", "text": "Now within a metal, electrons move with great ease from one point to another."}, {"title": "The Periodic Table .txt", "text": "And that means our metals are able to conduct electricity very well."}, {"title": "The Periodic Table .txt", "text": "So metals generally have high connectivity rates."}, {"title": "The Periodic Table .txt", "text": "Now metals are also malleable, which means you can hammer them into very thin strips."}, {"title": "The Periodic Table .txt", "text": "Examples include wires."}, {"title": "The Periodic Table .txt", "text": "Now metals are also or have high ductility rates."}, {"title": "The Periodic Table .txt", "text": "In other words, they're stretchy or stretchable."}, {"title": "The Periodic Table .txt", "text": "Now metals, whenever they form compounds with oxygen, they form or bond non Covalently."}, {"title": "The Periodic Table .txt", "text": "They create ionic oxides."}, {"title": "The Periodic Table .txt", "text": "The one exception is Beryllium."}, {"title": "The Periodic Table .txt", "text": "Beryllium bonds with oxygen Covalently."}, {"title": "The Periodic Table .txt", "text": "And that's the only exception known."}, {"title": "The Periodic Table .txt", "text": "Now let's look at the second type of division, namely the nonmetals."}, {"title": "The Periodic Table .txt", "text": "Now nonmetals, which are found on the right side of the table."}, {"title": "The Periodic Table .txt", "text": "The red guys have very diverse chemical characteristics."}, {"title": "The Periodic Table .txt", "text": "And these guys form negative ions."}, {"title": "The Periodic Table .txt", "text": "They don't lose electrons very easily."}, {"title": "The Periodic Table .txt", "text": "In fact, they gain electrons more easily than metals and that's why they form negative oxidation states."}, {"title": "The Periodic Table .txt", "text": "Now, these guys, when they combine with oxygen, they form covalent oxides."}, {"title": "The Periodic Table .txt", "text": "Examples include carbon dioxide or carbon monoxide."}, {"title": "The Periodic Table .txt", "text": "Now, let's look at the third type division called the metalloids."}, {"title": "The Periodic Table .txt", "text": "metalloids are interesting in that they have characteristics of both metals and nonmetals."}, {"title": "The Periodic Table .txt", "text": "And these guys are found right here in the middle of our periodic table or mortal towards the mid right."}, {"title": "The Periodic Table .txt", "text": "The orange guys are the metalloids."}, {"title": "Avogadro's Law .txt", "text": "So, as of now, we spoke of two laws charles Law and Boyle's Law."}, {"title": "Avogadro's Law .txt", "text": "And we saw that these laws both helped us explain exactly how gas molecules interact and function on the macroscopic level."}, {"title": "Avogadro's Law .txt", "text": "Now we're going to look at a third law called Avocadoso's Law."}, {"title": "Avogadro's Law .txt", "text": "And we're going to see how this law also helps us gain more intuition about the interactions of gas molecules on a macroscopic level."}, {"title": "Avogadro's Law .txt", "text": "So let's look at the conditions under which this law holds."}, {"title": "Avogadro's Law .txt", "text": "So this law will only work when our pressure and temperature are both held constant."}, {"title": "Avogadro's Law .txt", "text": "And what this law tells us is that volume is directly proportional to the number of moles."}, {"title": "Avogadro's Law .txt", "text": "And what that means."}, {"title": "Avogadro's Law .txt", "text": "If these guys are held constant, the only way we can increase our volume of our system is to add more gas or to add more moles of gas."}, {"title": "Avogadro's Law .txt", "text": "Now, if we multiply this side by some constant, this we set equal and our N comes to this side."}, {"title": "Avogadro's Law .txt", "text": "We get the following relation."}, {"title": "Avogadro's Law .txt", "text": "Volume over N, our number of moles equals a constant."}, {"title": "Avogadro's Law .txt", "text": "Now this constant, which we will see next when we learn about the ideal gas law, depends on temperature and pressure."}, {"title": "Avogadro's Law .txt", "text": "In other words, if our pressure and temperature are the same, then our constant will always be the same."}, {"title": "Avogadro's Law .txt", "text": "But if we increase or decrease our temperature or pressure, our constant will also change."}, {"title": "Avogadro's Law .txt", "text": "So that brings up an interesting relation."}, {"title": "Avogadro's Law .txt", "text": "That basically means as long as our pressure and temperature are the same, this will always be true for any volume or for any number of moles."}, {"title": "Avogadro's Law .txt", "text": "This will always be our constant."}, {"title": "Avogadro's Law .txt", "text": "And we'll see why this is important in Part D. Let's look at C for a second."}, {"title": "Avogadro's Law .txt", "text": "It's important to mention that experimental results show that a zero degree Celsius or 273 Kelvin and 1 ATM and pressure 1 mol of any gas, any gas whatsoever, will always correspond to 22.4\nliters."}, {"title": "Avogadro's Law .txt", "text": "And that's because according to our Kinetic Molecular Theory, volume of gas is zero."}, {"title": "Avogadro's Law .txt", "text": "It's assumed to be zero."}, {"title": "Avogadro's Law .txt", "text": "And so it doesn't matter what type of gas you use, if it's large or small, it will have a volume of 22.4 liters."}, {"title": "Avogadro's Law .txt", "text": "Now, this is according to experimental results."}, {"title": "Avogadro's Law .txt", "text": "Once again, something we observe experimentally, we turn into a theory."}, {"title": "Avogadro's Law .txt", "text": "And that's where our assumptions from our kinetic theory came."}, {"title": "Avogadro's Law .txt", "text": "Let's look at Part D.\nSo earlier I said that for any given temperature and pressure, as long as they are held constant at that same temperature and pressure, our constant will always be the same."}, {"title": "Avogadro's Law .txt", "text": "So suppose that's our case."}, {"title": "Avogadro's Law .txt", "text": "Suppose I have a system under which I have constant temperature and pressure."}, {"title": "Avogadro's Law .txt", "text": "Now, suppose I have a balloon at some volume one and some volume two."}, {"title": "Avogadro's Law .txt", "text": "And suppose I have three molecules or three moles on my gas inside my balloon."}, {"title": "Avogadro's Law .txt", "text": "What if I increase the number of moles to six moles?"}, {"title": "Avogadro's Law .txt", "text": "What will happen to my volume?"}, {"title": "Avogadro's Law .txt", "text": "Well, suppose I take a balloon and I put a liter of water into my balloon, it's going to fill up to a certain volume."}, {"title": "Avogadro's Law .txt", "text": "Suppose I put one more liter of water into my balloon."}, {"title": "Avogadro's Law .txt", "text": "Well, it's going to take up twice as much volume because we're assuming, of course, that temperature and pressure is the same."}, {"title": "Avogadro's Law .txt", "text": "So our Law of Evangels Law becomes the following this law holds for two sets of different conditions under which temperature and pressure is held the same."}, {"title": "Avogadro's Law .txt", "text": "So for one condition, for one volume in one mode, this guy equals the second condition, v two over n two."}, {"title": "Avogadro's Law .txt", "text": "The same thing."}, {"title": "Avogadro's Law .txt", "text": "The same results we saw in Charles Law and also in Boyle's Law."}, {"title": "Avogadro's Law .txt", "text": "Except in Boyle's Law it was p times V equals p two times V two."}, {"title": "Avogadro's Law .txt", "text": "Now this guy is equal to the constant, because remember, no matter what volume or number of mold we're talking about, as long as this is true, our constant will be the same."}, {"title": "Avogadro's Law .txt", "text": "So both this guy and this guy equals the same constant."}, {"title": "Avogadro's Law .txt", "text": "Now, this formula can be applied in many different examples."}, {"title": "Avogadro's Law .txt", "text": "Let's see one, an easy one in Part E. Suppose I'm given that for three moles, my volume is 22 liters."}, {"title": "Avogadro's Law .txt", "text": "Now suppose my second volume in my second condition is 44 liters."}, {"title": "Avogadro's Law .txt", "text": "What is my mole?"}, {"title": "Avogadro's Law .txt", "text": "What?"}, {"title": "Avogadro's Law .txt", "text": "I basically plug in my values."}, {"title": "Avogadro's Law .txt", "text": "22 over three equals 44 over n two."}, {"title": "Avogadro's Law .txt", "text": "I solve for n and I find six."}, {"title": "Avogadro's Law .txt", "text": "That's exactly how I use Avogadro's Law to solve problems."}, {"title": "Avogadro's Law .txt", "text": "So now let's explain Avogadro's Law, a macro scale concept using a microscale concept or the kinetic theory or the Kinetic molecular theory."}, {"title": "Avogadro's Law .txt", "text": "Now, Kinetic theory explains of Agadro's Law in the following way."}, {"title": "Avogadro's Law .txt", "text": "Now if temperature and pressure is to remain constant, an increase in the number of moles will increase volume."}, {"title": "Avogadro's Law .txt", "text": "In other words, if our kinetic energy or average kinetic energy of our molecules is to remain the same, and the pressure or the force per unit area exerted by or on the walls of my container is to remain the same, that means when we increase the number of moles, we also increase the number of molecules hitting the walls."}, {"title": "Avogadro's Law .txt", "text": "And that means the only way to keep these two guys constant is if we increase the volume."}, {"title": "Avogadro's Law .txt", "text": "That's exactly how our kinetic theory explains Abogro's Law."}, {"title": "Avogadro's Law .txt", "text": "Now, once again, to recap, kinetic theory explains microscopic concepts."}, {"title": "Avogadro's Law .txt", "text": "It explains how two individual gas molecules interact."}, {"title": "Avogadro's Law .txt", "text": "The fact that their volume is so small that it's assumed to be zero."}, {"title": "Avogadro's Law .txt", "text": "The fact that individual molecules travel at very high speeds, about 1000 these laws avoidros Charles and Boyle's Law all explain macroscopic concepts, things that you could see and feel and hear."}, {"title": "Avogadro's Law .txt", "text": "For example, a balloon popping when you're putting pressure on it, or a balloon inflating when you're putting in more molds."}, {"title": "Avogadro's Law .txt", "text": "Things like that are explained by these three laws."}, {"title": "Avogadro's Law .txt", "text": "Next, we're going to look at an overall law called the Ideal Gas Law, which incorporates all three laws."}, {"title": "Sp3 Hybridization.txt", "text": "So, in this lecture, we're going to examine SP three hybridization."}, {"title": "Sp3 Hybridization.txt", "text": "So let's define it."}, {"title": "Sp3 Hybridization.txt", "text": "Well, this is defined as simply the combination of four atomic orbitals in a given atom to produce four hybridized orbitals which then can interact with other atomic orbitals of other atoms to produce codalent bonds."}, {"title": "Sp3 Hybridization.txt", "text": "So to show this, let's examine the following methane molecule."}, {"title": "Sp3 Hybridization.txt", "text": "So, our goal will be to produce this methane molecule composed of one carbon and four H atoms."}, {"title": "Sp3 Hybridization.txt", "text": "So the carbon has the following electron configuration."}, {"title": "Sp3 Hybridization.txt", "text": "It has a total of six electrons."}, {"title": "Sp3 Hybridization.txt", "text": "Two electrons go to the one S, two electrons go to the two S and two electrons still to two P. Now, each H atom has one electron each."}, {"title": "Sp3 Hybridization.txt", "text": "And that means that electron goes into the one x orbital."}, {"title": "Sp3 Hybridization.txt", "text": "So we have one balance electron per H atom and four balance electrons two plus two four for the carbon atom."}, {"title": "Sp3 Hybridization.txt", "text": "Now, before the carbon can combine with the H atoms to form our methane, hybridization must take place."}, {"title": "Sp3 Hybridization.txt", "text": "Remember, hybridization occurs because it increases the volume of the lobe interacting with the other atomic orbitals."}, {"title": "Sp3 Hybridization.txt", "text": "And this increase in overlap will increase the strength of the bond."}, {"title": "Sp3 Hybridization.txt", "text": "So hybridization takes place so that there is a better overlap between atomic orbitals and this stabilizes the bond."}, {"title": "Sp3 Hybridization.txt", "text": "So before hybridization took place, we had the following picture of our carbon atom."}, {"title": "Sp3 Hybridization.txt", "text": "So, the carbon atom has four bounce electrons."}, {"title": "Sp3 Hybridization.txt", "text": "Two bounce electrons are in the two S orbitals shown here."}, {"title": "Sp3 Hybridization.txt", "text": "One bounce electron is in the two PX, one balanced electron is in the two PY and no electrons are in the two PZ."}, {"title": "Sp3 Hybridization.txt", "text": "So how does hybridization take place?"}, {"title": "Sp3 Hybridization.txt", "text": "Well, first we must ask the following question how many hybrid orbitals should carbon develop so that it can create the methane molecule?"}, {"title": "Sp3 Hybridization.txt", "text": "The answer lies in this picture."}, {"title": "Sp3 Hybridization.txt", "text": "How many bonds are created between the carbon and the H?"}, {"title": "Sp3 Hybridization.txt", "text": "Well, since we have one carbon and four HS, there are four bonds."}, {"title": "Sp3 Hybridization.txt", "text": "So that means we need four hybrid orbitals."}, {"title": "Sp3 Hybridization.txt", "text": "So that means we have to use the two x and all the three P, x's, y's and Z's to form our four hybrid orbitals."}, {"title": "Sp3 Hybridization.txt", "text": "In other words, for hybridization to take place, the two S must combine the two PX that must combine the two PY and the two PZ."}, {"title": "Sp3 Hybridization.txt", "text": "If we combine all these four atomic orbitals, we will get four hybrid orbitals that are all identical and look like this."}, {"title": "Sp3 Hybridization.txt", "text": "So we get four SP, three hybridized orbitals in which we have 25% S character and 75% P character."}, {"title": "Sp3 Hybridization.txt", "text": "So this guy undergoes hybridization, we get the following depiction."}, {"title": "Sp3 Hybridization.txt", "text": "So now our carbon atom no longer has that individual two S and these individual two PX two PY, two PZ."}, {"title": "Sp3 Hybridization.txt", "text": "Instead, we have four identical XP, three hybridized orbitals."}, {"title": "Sp3 Hybridization.txt", "text": "And so and since we have four balanced electrons, each bounced electron goes into each of the four identical SP three hybridized orbitals."}, {"title": "Sp3 Hybridization.txt", "text": "So one goes into here, one goes into here, one in here and one in here."}, {"title": "Sp3 Hybridization.txt", "text": "Now, the carbon, which has undergone hybridization, is ready to interact with four other one s orbitals."}, {"title": "Sp3 Hybridization.txt", "text": "So here we take the four one s orbitals."}, {"title": "Sp3 Hybridization.txt", "text": "We place each on to the positive green lobe, and we get our methane molecule."}, {"title": "Sp3 Hybridization.txt", "text": "So a simpler way of looking at it is via this black diagram."}, {"title": "Sp3 Hybridization.txt", "text": "So here we have our carbon nucleus."}, {"title": "Sp3 Hybridization.txt", "text": "We have these SP three lobes, which each have an electron."}, {"title": "Sp3 Hybridization.txt", "text": "They interact with a one s orbital."}, {"title": "Sp3 Hybridization.txt", "text": "So H, with one electron, they bind or bonds."}, {"title": "Sp3 Hybridization.txt", "text": "And we create the following picture."}, {"title": "Sp3 Hybridization.txt", "text": "Notice that these guys are identical."}, {"title": "Sp3 Hybridization.txt", "text": "Now, for our methane molecule."}, {"title": "Sp3 Hybridization.txt", "text": "Experimentally, we know that the bond between a two ch and C H is 109 degrees."}, {"title": "Sp3 Hybridization.txt", "text": "And this takes the form of a tetrahedron."}, {"title": "Sp3 Hybridization.txt", "text": "So now let's look at the energy diagram."}, {"title": "Sp3 Hybridization.txt", "text": "So, let's say we want to combine one of these one SS with the SP three hypothetical orbital."}, {"title": "Sp3 Hybridization.txt", "text": "So that one s will be slightly lower in energy than the SP three."}, {"title": "Sp3 Hybridization.txt", "text": "The SP three will be slightly higher."}, {"title": "Sp3 Hybridization.txt", "text": "They will combine to form a bonding and an antibanding orbital or a molecular orbital."}, {"title": "Sp3 Hybridization.txt", "text": "So here we have the bonding, and the electrons will go into this orbital."}, {"title": "Sp3 Hybridization.txt", "text": "And here we have the antibinding."}, {"title": "Sp3 Hybridization.txt", "text": "Electrons will not want to go into this orbital."}, {"title": "Sp3 Hybridization.txt", "text": "They will stay in this bonding orbital."}, {"title": "Sp3 Hybridization.txt", "text": "And so this is exactly what happens in this picture."}, {"title": "Sp3 Hybridization.txt", "text": "Except this happens four times."}, {"title": "Nernst Equation Part II .txt", "text": "So now let's simplify the formula we just found."}, {"title": "Nernst Equation Part II .txt", "text": "We noticed that we have a common term negative n times F plus divide the whole equation by negative n times F. What we get is this whole guy here."}, {"title": "Nernst Equation Part II .txt", "text": "So these guys cancel, this guy becomes negative."}, {"title": "Nernst Equation Part II .txt", "text": "And now we have the denominator on this term here."}, {"title": "Nernst Equation Part II .txt", "text": "This equation is called a nurse equation and it can be used, used to find a cell voltage under non standard state conditions whereas this guy is our cell voltage under nonsense state conditions."}, {"title": "Nernst Equation Part II .txt", "text": "So we basically plug this guy in and all these guys in and we get our cell voltage for nonstand state conditions."}, {"title": "Nernst Equation Part II .txt", "text": "Now, this guy can be simplified even further because notice we have a constant R, a constant F. And if we're given some constant temperature, say 25 degrees Celsius, the most common temperature, room temperature, we can plug these guys in and simplify this whole guy to simply this guy here."}, {"title": "Nernst Equation Part II .txt", "text": "Look, we rewrite this formula, we get this."}, {"title": "Nernst Equation Part II .txt", "text": "We plug in our constant, our gas constant, our temperature in Kelvin and our Faraday's constant."}, {"title": "Nernst Equation Part II .txt", "text": "We plug this into the calculator and we get this number to be zero point 25 seven."}, {"title": "Nernst Equation Part II .txt", "text": "So this is a simplified version of this guy."}, {"title": "Nernst Equation Part II .txt", "text": "But we're not done."}, {"title": "Nernst Equation Part II .txt", "text": "Notice we have natural logs."}, {"title": "Nernst Equation Part II .txt", "text": "We never want to deal with natural logs."}, {"title": "Nernst Equation Part II .txt", "text": "We always want to convert natural logs into easier logs, say log base ten."}, {"title": "Nernst Equation Part II .txt", "text": "So that means we have to use this mathematical formula that relates bases of logs."}, {"title": "Nernst Equation Part II .txt", "text": "And what we basically have to realize is that natural log of Q is the same thing as this guy divided by this guy."}, {"title": "Nernst Equation Part II .txt", "text": "It's just a formula."}, {"title": "Nernst Equation Part II .txt", "text": "You can look that up online."}, {"title": "Nernst Equation Part II .txt", "text": "So we take this guy, we plug it into this Lnq and that means we are left with log base ten Q on the top."}, {"title": "Nernst Equation Part II .txt", "text": "And on the bottom we have this log of base ten of E. We plug this into the calculator and then we divide zero point 25 by this number to get our 0.0\n59 two."}, {"title": "Nernst Equation Part II .txt", "text": "So once again, we take this guy, we plug it into this LMQ, we use a calculator to find this number and our final nurse equation at 25 degrees Celsius is this following equation."}, {"title": "Nernst Equation Part II .txt", "text": "Now, if this was a different temperature, I'd go back to my equation in part E and I'd plug in a different temperature here and solve it the same way and get a new value here."}, {"title": "Nernst Equation Part II .txt", "text": "Now, last thing I want to mention is notice that if Q is equal to one, that means our log of one is zero."}, {"title": "Nernst Equation Part II .txt", "text": "So what we guess is our cell voltage is simply cell voltage under state and state conditions."}, {"title": "Nernst Equation Part II .txt", "text": "And that means this holds true as well."}, {"title": "Nernst Equation Part II .txt", "text": "Well, why is this the case?"}, {"title": "Nernst Equation Part II .txt", "text": "Well, if our Q is one, that means this Q is one."}, {"title": "Nernst Equation Part II .txt", "text": "So our ratio of concentration of products or reactions is one."}, {"title": "Nernst Equation Part II .txt", "text": "That means this guy, this guy and this guy."}, {"title": "Nernst Equation Part II .txt", "text": "This guy has molarity of one."}, {"title": "Nernst Equation Part II .txt", "text": "But that simply stands the condition, right?"}, {"title": "Nernst Equation Part II .txt", "text": "It's assumed that molarity is one under those conditions."}, {"title": "Nernst Equation Part II .txt", "text": "That's exactly what this states."}, {"title": "Nernst Equation Part II .txt", "text": "Now, also notice what this formula states."}, {"title": "Nernst Equation Part II .txt", "text": "It basically states that it's if our Q is bigger than one, if it's large, that means our final voltage will be less than our voltage under standard conditions."}, {"title": "Nernst Equation Part II .txt", "text": "And that makes sense because that's exactly what Leshak Leer principle says."}, {"title": "Nernst Equation Part II .txt", "text": "It says that if we have more product now, our reaction will be less product favorite and more reacting favored."}, {"title": "Introduction to Gas State .txt", "text": "So gas molecules have generally different properties than that of liquid molecules or solid molecules."}, {"title": "Introduction to Gas State .txt", "text": "Now, in this lecture, I'm going to give a brief introduction to the gas state."}, {"title": "Introduction to Gas State .txt", "text": "So, gas molecules travel at very, very high velocities at approximately 1000 mph or 480 meters/second."}, {"title": "Introduction to Gas State .txt", "text": "Now, that means if you allow single gas molecule to travel from New York to California without being interrupted, it would take it about 3 hours to get there versus a car that would take days and days."}, {"title": "Introduction to Gas State .txt", "text": "And so, because of this high speed, they feel very little force from other gas molecules and that means very little intermolecular bonding."}, {"title": "Introduction to Gas State .txt", "text": "Remember, the reason water is held together or any other solid is due to intermolecular bonding between the molecules."}, {"title": "Introduction to Gas State .txt", "text": "Now, in gas molecules we don't have that because the molecules move at high speeds when they pass each other, they don't really feel too much force, so they don't bond."}, {"title": "Introduction to Gas State .txt", "text": "Let's look at the second thing."}, {"title": "Introduction to Gas State .txt", "text": "So gases are compressible and that's because they take up much less volume than the volume of the container they are in."}, {"title": "Introduction to Gas State .txt", "text": "For example, let's look at this big ball, right?"}, {"title": "Introduction to Gas State .txt", "text": "So inside this ball we have air."}, {"title": "Introduction to Gas State .txt", "text": "And if you were to push this guy in, I could easily to some point push this ball in."}, {"title": "Introduction to Gas State .txt", "text": "Now, if this, if the inside was replaced with, say, salad or liquid, I wouldn't be able to push it without changing the volume."}, {"title": "Introduction to Gas State .txt", "text": "Notice how when I'm pushing this I'm not really affecting the volume too much, right?"}, {"title": "Introduction to Gas State .txt", "text": "And that's why I'm able to push it, I'm compressing it."}, {"title": "Introduction to Gas State .txt", "text": "And the reason for that is this following idea."}, {"title": "Introduction to Gas State .txt", "text": "Now, the volume of the inside of the ball is much greater than the volume that is taken up by these molecules."}, {"title": "Introduction to Gas State .txt", "text": "In other words, any two molecules at any given time are very far apart."}, {"title": "Introduction to Gas State .txt", "text": "So when I compress this ball, these molecules have lots of room to get closer, right?"}, {"title": "Introduction to Gas State .txt", "text": "So this model gets closer, this one gets closer, this one gets closer and eventually they all get closer so I could push them in."}, {"title": "Introduction to Gas State .txt", "text": "Now, if this guy was replaced with liquid or solid, liquid and solid is much more dense and that means I would not be able to push it together because all the molecules are close together."}, {"title": "Introduction to Gas State .txt", "text": "And that leads straight to the third point."}, {"title": "Introduction to Gas State .txt", "text": "Gas molecules exert a force on whatever they hit."}, {"title": "Introduction to Gas State .txt", "text": "And this force can be calculated in terms of pressure."}, {"title": "Introduction to Gas State .txt", "text": "So let's go back to this example, right?"}, {"title": "Introduction to Gas State .txt", "text": "So when I take my ball and I push this ball, I can only push it to a certain extent at some point."}, {"title": "Introduction to Gas State .txt", "text": "I can't push it any further unless I exert a stronger force."}, {"title": "Introduction to Gas State .txt", "text": "Well, why is that?"}, {"title": "Introduction to Gas State .txt", "text": "Well, the reason for that is because all these molecules are moving at tremendous velocities and every time they hit the container, hit the walls, they exert a force or a pressure."}, {"title": "Introduction to Gas State .txt", "text": "Pressure is simply force per some given area."}, {"title": "Introduction to Gas State .txt", "text": "And that means the added effect of all these molecules hitting the wall will be tremendous."}, {"title": "Introduction to Gas State .txt", "text": "And that's exactly why I can't push this ball any further than, say this, right?"}, {"title": "Introduction to Gas State .txt", "text": "So whenever we talk about force of molecules, force of gas molecules, we really want to talk about the pressure."}, {"title": "Introduction to Gas State .txt", "text": "And so when we talk about things like vapor pressure of a gas, vapor pressure is exactly this."}, {"title": "Introduction to Gas State .txt", "text": "It's the force that these molecules exert on the walls of the container at equilibrium that's vapor pressure."}, {"title": "Introduction to Gas State .txt", "text": "So let's jump into number or part D.\nSo gas molecules expand into container."}, {"title": "Introduction to Gas State .txt", "text": "And that's because whenever I have this container and does this container out of air, if I open this up, what will happen to gas molecules?"}, {"title": "Introduction to Gas State .txt", "text": "Well, remember, gas molecules are moving at high speeds."}, {"title": "Introduction to Gas State .txt", "text": "So if I open something up, they will escape."}, {"title": "Introduction to Gas State .txt", "text": "And also, because they're moving at high speeds, they don't feel intermocular attractions, so there's nothing stopping them from exiting into the container, so they can completely expand the container."}, {"title": "Introduction to Gas State .txt", "text": "And that means, on a similar note, different gases will mix completely because there is no inter molecular interactions between any two gas molecules."}, {"title": "Introduction to Gas State .txt", "text": "Now, compare this to liquids and solids, right?"}, {"title": "Introduction to Gas State .txt", "text": "If I take the same container of liquid and I spill it into the room, what will happen?"}, {"title": "Introduction to Gas State .txt", "text": "Well, they won't escape."}, {"title": "Introduction to Gas State .txt", "text": "They will just create a small puddle and they will stay there, right?"}, {"title": "Introduction to Gas State .txt", "text": "That's because they do experience intermolecular attractions and they don't have high velocities or high translational speeds."}, {"title": "Introduction to Gas State .txt", "text": "And that means these intermolecular attractions and low velocities will keep the molecules together."}, {"title": "Introduction to Gas State .txt", "text": "Now, of course, some of these guys will have enough kinetic energy to escape this environment, but that's a different idea."}, {"title": "Introduction to Gas State .txt", "text": "That's called evaporation."}, {"title": "Introduction to Gas State .txt", "text": "And when you evaporate from a liquid to a gas, the gas gains that high velocity escapes."}, {"title": "Introduction to Gas State .txt", "text": "And now it no longer experiences any intermolecular attractions."}, {"title": "Introduction to Gas State .txt", "text": "And the final thing we want to look at is the following."}, {"title": "Introduction to Gas State .txt", "text": "Now, we normally describe gas as using a few things temperature."}, {"title": "Introduction to Gas State .txt", "text": "And later we'll see how temperature and kinetic energy speed of our molecules are related."}, {"title": "Introduction to Gas State .txt", "text": "Pressure of our gas, the pressure that the gas exerts on the walls of the container, volume of the gas fills up, and the number of molecules normally in terms of moles."}, {"title": "Osmotic Pressure Example .txt", "text": "In this example, we are given 3 grams of some polymer dissolved in 20 solution and we know that admonic pressure is 1.3 times ten to the negative two ATMs at 25 degrees Celsius."}, {"title": "Osmotic Pressure Example .txt", "text": "We want to find the mole amounts of our polymer."}, {"title": "Osmotic Pressure Example .txt", "text": "So before we begin, I want to illustrate exactly, exactly what's meant by asthmaic pressure."}, {"title": "Osmotic Pressure Example .txt", "text": "So let's look at this system."}, {"title": "Osmotic Pressure Example .txt", "text": "Suppose we have two sides, one side and a second side."}, {"title": "Osmotic Pressure Example .txt", "text": "And the two sides are blocked off by a membrane."}, {"title": "Osmotic Pressure Example .txt", "text": "This membrane allows one to pass through, but does not allow our solid molecules to pass through."}, {"title": "Osmotic Pressure Example .txt", "text": "Now this side simply contains 20 solvent."}, {"title": "Osmotic Pressure Example .txt", "text": "This side contains a solution of 20 ML that contains 3 grams of our polymer."}, {"title": "Osmotic Pressure Example .txt", "text": "So the red dots are our polymer dots."}, {"title": "Osmotic Pressure Example .txt", "text": "Now what will happen?"}, {"title": "Osmotic Pressure Example .txt", "text": "Well, since the concentration of our solute is greater in this side, then water will tend to move from this side to this side, right?"}, {"title": "Osmotic Pressure Example .txt", "text": "So osmotic pressure basically says well, I need to apply this much pressure on this side of the membrane to stop the movement of that water, to stop osmosis from occurring."}, {"title": "Osmotic Pressure Example .txt", "text": "So that's what is meant by asthmatic pressure."}, {"title": "Osmotic Pressure Example .txt", "text": "So now we basically want to use all the given info and use our formula for asthmatic pressure and find our molar mass of polymer."}, {"title": "Osmotic Pressure Example .txt", "text": "Now, first step is let's write down our formula and let's see which ones we have and which ones we don't."}, {"title": "Osmotic Pressure Example .txt", "text": "So I we have I just simply won."}, {"title": "Osmotic Pressure Example .txt", "text": "And that's because our polymer doesn't associate into anything."}, {"title": "Osmotic Pressure Example .txt", "text": "So I is one."}, {"title": "Osmotic Pressure Example .txt", "text": "Our key in Kelvin is 25 plus 273 gives us 298 Kelvin."}, {"title": "Osmotic Pressure Example .txt", "text": "Our R is a constant."}, {"title": "Osmotic Pressure Example .txt", "text": "So it's zero point 81 litres times ATM over moles times Kelvin."}, {"title": "Osmotic Pressure Example .txt", "text": "And our molarity, well, we don't have our molarity, but we do have our asthma pressure."}, {"title": "Osmotic Pressure Example .txt", "text": "So this is what we want to find."}, {"title": "Osmotic Pressure Example .txt", "text": "And we want to find this guy and use that to find our grams per mole or molar mass."}, {"title": "Osmotic Pressure Example .txt", "text": "Because remember, molar mass is the amount of mass per 1 mol."}, {"title": "Osmotic Pressure Example .txt", "text": "So let's plug these guys in into this equation and we got this by rearranging this, by bringing all these guys on this side."}, {"title": "Osmotic Pressure Example .txt", "text": "So we got that."}, {"title": "Osmotic Pressure Example .txt", "text": "So we plug in our atmosphere pressure zero point 13 ATMs over our constant times, our temperature times I or one."}, {"title": "Osmotic Pressure Example .txt", "text": "So ATMs cancel, the Kelvins cancel and we get 5.31 times ten to negative four moles per liter."}, {"title": "Osmotic Pressure Example .txt", "text": "So this is our molarity."}, {"title": "Osmotic Pressure Example .txt", "text": "Now let's find the number of moles of polymer."}, {"title": "Osmotic Pressure Example .txt", "text": "If we find the number of moles of polymer, we could take our amount in grams, divide that by our moles and we get mol and mass or mass per mole."}, {"title": "Osmotic Pressure Example .txt", "text": "So 5.31 times ten to negative four molar which we got from here, times the amount of solution we have, which is 20 ML or 0.2 liters because we have to convert milliliters to liters."}, {"title": "Osmotic Pressure Example .txt", "text": "We divide this by thousand and we get to zero two the liters cancel and we get 1.6 times ten to negative four moles of polymer."}, {"title": "Osmotic Pressure Example .txt", "text": "And now we take our grams of polymer divided by our moles of polymer and we get 28,230 grams/mol or 28."}, {"title": "Osmotic Pressure Example .txt", "text": "That's our final answer."}, {"title": "Raoul\u2019s Law for Non-Ideal Fluids .txt", "text": "In this lecture, I will talk to you about role to offer nonideal fluids."}, {"title": "Raoul\u2019s Law for Non-Ideal Fluids .txt", "text": "Let's remember what a non ideal fluid is."}, {"title": "Raoul\u2019s Law for Non-Ideal Fluids .txt", "text": "A non ideal fluid is a fluid in which the volume of molecules is not neglected and intermolecular forces connecting the molecules exist."}, {"title": "Raoul\u2019s Law for Non-Ideal Fluids .txt", "text": "And these forces will play a role in decreasing the vapor repression of the fluid."}, {"title": "Raoul\u2019s Law for Non-Ideal Fluids .txt", "text": "And we'll see that in a second."}, {"title": "Raoul\u2019s Law for Non-Ideal Fluids .txt", "text": "Now, before we talk about that, let's talk about the heat of solution."}, {"title": "Raoul\u2019s Law for Non-Ideal Fluids .txt", "text": "Now, we have already spoken about heat of solution in another video, so let's briefly discuss it."}, {"title": "Raoul\u2019s Law for Non-Ideal Fluids .txt", "text": "So the heat of solution is the sum of energy required to break the intermolecular forces of compound one."}, {"title": "Raoul\u2019s Law for Non-Ideal Fluids .txt", "text": "Plus the sum of the energy is required to break the intermolecular forces of compound two plus the energy release when you form the new solution."}, {"title": "Raoul\u2019s Law for Non-Ideal Fluids .txt", "text": "And that gives you the enthalpy of solution or heat of solution."}, {"title": "Raoul\u2019s Law for Non-Ideal Fluids .txt", "text": "Now, when this guy is negative, when he's exothermic the bonds form are stronger than the bonds broken, so they're more stable."}, {"title": "Raoul\u2019s Law for Non-Ideal Fluids .txt", "text": "Now, when it's endothermic, when it's positive, the bonds form are weaker and less stable than the bonds that were broken."}, {"title": "Raoul\u2019s Law for Non-Ideal Fluids .txt", "text": "Now let's compare ideal and non ideal situations."}, {"title": "Raoul\u2019s Law for Non-Ideal Fluids .txt", "text": "Now, when we talk about ideal situations, we can graph Roth's law."}, {"title": "Raoul\u2019s Law for Non-Ideal Fluids .txt", "text": "And the Y axis is vapor pressure and the x axis is mole fraction."}, {"title": "Raoul\u2019s Law for Non-Ideal Fluids .txt", "text": "Now, we have two compounds here, compound A and compound B."}, {"title": "Raoul\u2019s Law for Non-Ideal Fluids .txt", "text": "Now for compound A when we go from here to here along the x axis the mole fraction increases."}, {"title": "Raoul\u2019s Law for Non-Ideal Fluids .txt", "text": "For compound B, when we go from here to here on the x axis the mole fraction decreases."}, {"title": "Raoul\u2019s Law for Non-Ideal Fluids .txt", "text": "The brown line represents the pressure."}, {"title": "Raoul\u2019s Law for Non-Ideal Fluids .txt", "text": "It's the slope for compound A and the green line represents the pressure of the slope for compound B."}, {"title": "Raoul\u2019s Law for Non-Ideal Fluids .txt", "text": "Now, as we go as we increase the mole concentration in compound one or compound A, the pressure of it increases."}, {"title": "Raoul\u2019s Law for Non-Ideal Fluids .txt", "text": "And as we go this way, the mole fraction of this guy compound B decreases."}, {"title": "Raoul\u2019s Law for Non-Ideal Fluids .txt", "text": "So as we go this way, the vapor pressure of compound B decreases."}, {"title": "Raoul\u2019s Law for Non-Ideal Fluids .txt", "text": "Now, at any given time, we could find a final vapor pressure and we find the final vapor pressure by summing the two pressures."}, {"title": "Raoul\u2019s Law for Non-Ideal Fluids .txt", "text": "So for example, say at this point the total pressure is this guy plus this guy gives you this plus this."}, {"title": "Raoul\u2019s Law for Non-Ideal Fluids .txt", "text": "So it's somewhere over here and that's what the red line is."}, {"title": "Raoul\u2019s Law for Non-Ideal Fluids .txt", "text": "Now this is for an ideal fluid."}, {"title": "Raoul\u2019s Law for Non-Ideal Fluids .txt", "text": "Now, in an ideal fluid the surface molecules are not connected by any intermolecular forces because remember, in an ideal fluid we're neglecting those intermolecular forces."}, {"title": "Raoul\u2019s Law for Non-Ideal Fluids .txt", "text": "So nothing holds the molecules together so they could freely escape into the environment if they have the kinetic energy."}, {"title": "Raoul\u2019s Law for Non-Ideal Fluids .txt", "text": "However, in a non ideal fluid there are intermolecular forces and these forces hold the molecules together."}, {"title": "Raoul\u2019s Law for Non-Ideal Fluids .txt", "text": "They inhibit the molecules from escaping into the environment."}, {"title": "Raoul\u2019s Law for Non-Ideal Fluids .txt", "text": "So at any given time, less molecules will be able to escape in a non ideal fluid than in an ideal fluid."}, {"title": "Raoul\u2019s Law for Non-Ideal Fluids .txt", "text": "And because there are less molecules present in the states above the pressure will be less."}, {"title": "Raoul\u2019s Law for Non-Ideal Fluids .txt", "text": "Therefore, the stronger the intermolecular forces, the less likely that they will evaporate."}, {"title": "Raoul\u2019s Law for Non-Ideal Fluids .txt", "text": "Likewise, the weaker the intermolecular forces holding the molecules together, the more likely that they will evaporate."}, {"title": "Raoul\u2019s Law for Non-Ideal Fluids .txt", "text": "Now, let's look at some graphs for non ideal fluids."}, {"title": "Raoul\u2019s Law for Non-Ideal Fluids .txt", "text": "Now in this graph we're going to compare two situations."}, {"title": "Raoul\u2019s Law for Non-Ideal Fluids .txt", "text": "We're going to compare positive or endothermic cube solution and negative or exothermicial solution."}, {"title": "Raoul\u2019s Law for Non-Ideal Fluids .txt", "text": "We're also going to compare non ideal situations we're presented to by dashed lines and ideal situations they're presented by solid lines."}, {"title": "Raoul\u2019s Law for Non-Ideal Fluids .txt", "text": "Now, in this graph, the y axis is vapor pressure and the x axis is the mole fraction."}, {"title": "Raoul\u2019s Law for Non-Ideal Fluids .txt", "text": "We're dealing with two compounds, compounds A, compound B."}, {"title": "Raoul\u2019s Law for Non-Ideal Fluids .txt", "text": "Compound B is the green line."}, {"title": "Raoul\u2019s Law for Non-Ideal Fluids .txt", "text": "Compound A is the brown line."}, {"title": "Raoul\u2019s Law for Non-Ideal Fluids .txt", "text": "Now, in an endothermic reaction the bonds form are weaker than the bonds broken."}, {"title": "Raoul\u2019s Law for Non-Ideal Fluids .txt", "text": "And that means the bonds formed are going to be less likely to hold the molecules on the surface."}, {"title": "Raoul\u2019s Law for Non-Ideal Fluids .txt", "text": "That means more molecules will evaporate."}, {"title": "Raoul\u2019s Law for Non-Ideal Fluids .txt", "text": "And if more molecules evaporate, more molecules will be present in the space above, more gas molecules."}, {"title": "Raoul\u2019s Law for Non-Ideal Fluids .txt", "text": "And if more gas molecules are present in the space above, the vapor pressure is higher."}, {"title": "Raoul\u2019s Law for Non-Ideal Fluids .txt", "text": "Therefore, compared to ideal situations for each case in a non ideal situation that's endothermic the pressure for each will be higher and that's why they curve upward."}, {"title": "Raoul\u2019s Law for Non-Ideal Fluids .txt", "text": "Now, in an exothermic, the opposite holds."}, {"title": "Raoul\u2019s Law for Non-Ideal Fluids .txt", "text": "In an exothermic reaction, the bonds formed are stronger than the bonds broken."}, {"title": "Raoul\u2019s Law for Non-Ideal Fluids .txt", "text": "Therefore, the final solution will hold its molecules very tightly and will not let them go."}, {"title": "Raoul\u2019s Law for Non-Ideal Fluids .txt", "text": "They will not be able to escape, will be less likely to go into the gas state."}, {"title": "Raoul\u2019s Law for Non-Ideal Fluids .txt", "text": "And that's why less gas molecules will be present in the space above and the deeper pressure will be lower."}, {"title": "Raoul\u2019s Law for Non-Ideal Fluids .txt", "text": "And that's why in each situation they're curved downward."}, {"title": "Raoul\u2019s Law for Non-Ideal Fluids .txt", "text": "So if you look at the pressure at any given point it's going to be lower than the ideal pressure."}, {"title": "Gibbs Free Energy Derivation .txt", "text": "In this lecture, I will show you where the Gibbs free energy equation comes from."}, {"title": "Gibbs Free Energy Derivation .txt", "text": "But before we talk about that, we must talk about a few important things."}, {"title": "Gibbs Free Energy Derivation .txt", "text": "Firstly, whenever we talk about gives free energy, we talk about closed systems or reactions occurring under closed systems."}, {"title": "Gibbs Free Energy Derivation .txt", "text": "So what is a closed system?"}, {"title": "Gibbs Free Energy Derivation .txt", "text": "A closed system simply means that no mass is exchanged, only energy is exchanged."}, {"title": "Gibbs Free Energy Derivation .txt", "text": "And since mass is matter, and matter are molecules, that means no molecules go into the system and no molecules lead the system."}, {"title": "Gibbs Free Energy Derivation .txt", "text": "So the number of moles remains constant."}, {"title": "Gibbs Free Energy Derivation .txt", "text": "Secondly, reactions are under constant temperature and pressure."}, {"title": "Gibbs Free Energy Derivation .txt", "text": "If this wasn't true, the equation would break down."}, {"title": "Gibbs Free Energy Derivation .txt", "text": "It would not work."}, {"title": "Gibbs Free Energy Derivation .txt", "text": "So according to the ideal gas law, when number of moles is held constant, temperature is held constant, and pressure is held constant, then volume must remain constant."}, {"title": "Gibbs Free Energy Derivation .txt", "text": "If volume is constant, then change in volume is zero, because the final and the initial are the same."}, {"title": "Gibbs Free Energy Derivation .txt", "text": "So the TV work done is zero."}, {"title": "Gibbs Free Energy Derivation .txt", "text": "And that means that we could approximate change in enthalpy."}, {"title": "Gibbs Free Energy Derivation .txt", "text": "And simply change in enthalpy of the system is equal to change in internal energy or simply change in energy."}, {"title": "Gibbs Free Energy Derivation .txt", "text": "The PV term disappears because it's zero."}, {"title": "Gibbs Free Energy Derivation .txt", "text": "Now thirdly, reactions are reversible, which means that if this wasn't true, the equation would break down as well."}, {"title": "Gibbs Free Energy Derivation .txt", "text": "Now, since reactions are reversible and enthalpy is a state function, hess's law tells us the change in enthalpy of the four reaction is equal to the negative change in enthalpy of the reverse reaction."}, {"title": "Gibbs Free Energy Derivation .txt", "text": "So if we look at this reversible reaction here, a plus B is equal to C plus D, where the change in enthalpy is negative ten."}, {"title": "Gibbs Free Energy Derivation .txt", "text": "And the reverse reaction, according to Hess's Law, is C plus D equal A plus B, and this is negative of this."}, {"title": "Gibbs Free Energy Derivation .txt", "text": "So it's positive ten kilojoules per mole."}, {"title": "Gibbs Free Energy Derivation .txt", "text": "The last thing we should mention is the mathematical formula for entropy, which basically states that change in entropy is the heat or change in energy over time, over temperature, and temperature is in Kelvin."}, {"title": "Gibbs Free Energy Derivation .txt", "text": "Step one."}, {"title": "Gibbs Free Energy Derivation .txt", "text": "In step one, I apply the formula for a change in entropy."}, {"title": "Gibbs Free Energy Derivation .txt", "text": "That is, change in entropy surroundings is equal to change in energy over temperature, as seen here."}, {"title": "Gibbs Free Energy Derivation .txt", "text": "Step two remember when we talk about free energy, or gifts free energy, we talk about a closed system, constant pressure and constant temperature."}, {"title": "Gibbs Free Energy Derivation .txt", "text": "And what this basically means, according to the ideal gas law, is that volume is constant."}, {"title": "Gibbs Free Energy Derivation .txt", "text": "So change in volume is zero."}, {"title": "Gibbs Free Energy Derivation .txt", "text": "So the PV work done is zero."}, {"title": "Gibbs Free Energy Derivation .txt", "text": "So when we look at the equation for change in enthalpy, the PV work term disappears."}, {"title": "Gibbs Free Energy Derivation .txt", "text": "And that means that our equation becomes change in enthalpy."}, {"title": "Gibbs Free Energy Derivation .txt", "text": "The surroundings is equal to change in energy or heat."}, {"title": "Gibbs Free Energy Derivation .txt", "text": "So this becomes this."}, {"title": "Gibbs Free Energy Derivation .txt", "text": "Now, step three remember when we talk about Gibbs free energy, we talk about a reversible reaction."}, {"title": "Gibbs Free Energy Derivation .txt", "text": "And because enthalpy is a state function, according to Hess's law, hess's law states that the entropy change of the forward reaction is equal to the negative entropy change of the reverse reaction."}, {"title": "Gibbs Free Energy Derivation .txt", "text": "So the amount of energy that leaves the system is the same amount of energy, except negative that into the system."}, {"title": "Gibbs Free Energy Derivation .txt", "text": "Okay?"}, {"title": "Gibbs Free Energy Derivation .txt", "text": "So the magnitude remains the same, but the signs change."}, {"title": "Gibbs Free Energy Derivation .txt", "text": "Therefore, the change in entropy of the surroundings is equal to negative change in entropy of the system."}, {"title": "Gibbs Free Energy Derivation .txt", "text": "Step four."}, {"title": "Gibbs Free Energy Derivation .txt", "text": "Remember, change in entropy of the universe is equal to change in entropy the surroundings plus change in entropy of the system."}, {"title": "Gibbs Free Energy Derivation .txt", "text": "Now, this guy equals this guy."}, {"title": "Gibbs Free Energy Derivation .txt", "text": "Our next step will be to see that this guy can be replaced by this guy, okay?"}, {"title": "Gibbs Free Energy Derivation .txt", "text": "And that's exactly what we do in step five."}, {"title": "Gibbs Free Energy Derivation .txt", "text": "We simply take this and plug it into here."}, {"title": "Gibbs Free Energy Derivation .txt", "text": "And that's what we get."}, {"title": "Gibbs Free Energy Derivation .txt", "text": "Here."}, {"title": "Gibbs Free Energy Derivation .txt", "text": "The next step we multiply out by negative t.\nAnd that's because we want to get rid of this t, okay?"}, {"title": "Gibbs Free Energy Derivation .txt", "text": "So let's do that."}, {"title": "Gibbs Free Energy Derivation .txt", "text": "Negative t times this gives you this negative t times this gives you that negative t times a negative whatever gives us a positive."}, {"title": "Gibbs Free Energy Derivation .txt", "text": "So plus this whole term, step seven, is basically the TS cancel out."}, {"title": "Gibbs Free Energy Derivation .txt", "text": "So we get this whole thing minus these t's."}, {"title": "Gibbs Free Energy Derivation .txt", "text": "Next step, what I do is I switch these guys to make it look more like the actual equation."}, {"title": "Gibbs Free Energy Derivation .txt", "text": "And now I equate this to changing Gibbs energy."}, {"title": "Gibbs Free Energy Derivation .txt", "text": "And now I get our final equation change."}, {"title": "Gibbs Free Energy Derivation .txt", "text": "In Gibbs, the energy is equal to change in entropy of the system minus temperature times change in entropy of the system."}, {"title": "Gibbs Free Energy Derivation .txt", "text": "The point was to change surroundings to system so that all the terms in a final equation are of the system."}, {"title": "Gibbs Free Energy Derivation .txt", "text": "And I basically equated negative times change in entropy of the universe with negative or I'm sorry, with change in Gibbs free energy."}, {"title": "Gibbs Free Energy Derivation .txt", "text": "And that's how you get Gibbs free energy equation."}, {"title": "Carbon and Nitrogen Groups .txt", "text": "In this lecture we're going to look at and compare two more important groups found in our periodic table."}, {"title": "Carbon and Nitrogen Groups .txt", "text": "We're going to look at group 14 or four A and group 15 and five A elements."}, {"title": "Carbon and Nitrogen Groups .txt", "text": "Now let's begin with the group 14 or four A elements."}, {"title": "Carbon and Nitrogen Groups .txt", "text": "Now this group consists of five elements or at least five elements."}, {"title": "Carbon and Nitrogen Groups .txt", "text": "And the important elements are are listed below."}, {"title": "Carbon and Nitrogen Groups .txt", "text": "We have carbon, which is a nonmetal."}, {"title": "Carbon and Nitrogen Groups .txt", "text": "We have silicon, which is a metalloid."}, {"title": "Carbon and Nitrogen Groups .txt", "text": "We have germanium, which is also a metalloid."}, {"title": "Carbon and Nitrogen Groups .txt", "text": "And we have two metals, tin and lead."}, {"title": "Carbon and Nitrogen Groups .txt", "text": "Now notice that in our group we have at least one of each."}, {"title": "Carbon and Nitrogen Groups .txt", "text": "We have at least one nonmetal, at least one metalloid and at least one metal."}, {"title": "Carbon and Nitrogen Groups .txt", "text": "Now every single element within this group can form four Covalent bonds with other nonmetals."}, {"title": "Carbon and Nitrogen Groups .txt", "text": "And every atom except the sea atom, except our carbon can form two more additional bonds with lowest bases."}, {"title": "Carbon and Nitrogen Groups .txt", "text": "Now remember what a lewis bases."}, {"title": "Carbon and Nitrogen Groups .txt", "text": "It's simply an atom or a molecule that has an extra lone pair of electrons that it can donate to some other lewis acid."}, {"title": "Carbon and Nitrogen Groups .txt", "text": "Now let's look at D. Now, only carbon is capable of forming strong pi bonds."}, {"title": "Carbon and Nitrogen Groups .txt", "text": "In other words, it can form a strong double bond or a strong triple bond."}, {"title": "Carbon and Nitrogen Groups .txt", "text": "No other atom found in our group 14 or four A has that capability."}, {"title": "Carbon and Nitrogen Groups .txt", "text": "Now let's jump to group 15."}, {"title": "Carbon and Nitrogen Groups .txt", "text": "In group 15 or five A, we have also at least five atoms."}, {"title": "Carbon and Nitrogen Groups .txt", "text": "These are the important atoms listed."}, {"title": "Carbon and Nitrogen Groups .txt", "text": "So we have nitrogen and phosphorus, which is a nonmetal or both nonmetals."}, {"title": "Carbon and Nitrogen Groups .txt", "text": "We have arsenic and antimony, which are both metalloids, and bismuth, which is a metal."}, {"title": "Carbon and Nitrogen Groups .txt", "text": "Now once again, just like group 14 or four A, we have at least one of each in our group 15 or five day."}, {"title": "Carbon and Nitrogen Groups .txt", "text": "Now, unlike this group which forms four Covalent bonds with other nonmetals, group 15 or five day forms three Covalent bonds and in addition, every single atom, except that nitrogen can form two more bonds using their higher D orbitals."}, {"title": "Carbon and Nitrogen Groups .txt", "text": "Now we're going to talk more about D orbitals and P orbitals and S orbitals in another lecture."}, {"title": "Carbon and Nitrogen Groups .txt", "text": "Let's look at C. Now nitrogen, this atom can form pi bonds just like carbon can form pi bonds in group 14."}, {"title": "Carbon and Nitrogen Groups .txt", "text": "And these pi bonds can be triple bonds or double bonds."}, {"title": "Carbon and Nitrogen Groups .txt", "text": "And they're relatively strong."}, {"title": "Carbon and Nitrogen Groups .txt", "text": "But unlike this group, we have one more atom here, our phosphorus, that can form a double bond, but it's a weak double bond."}, {"title": "Carbon and Nitrogen Groups .txt", "text": "But regardless, it's still a double bond, a pi bond."}, {"title": "Carbon and Nitrogen Groups .txt", "text": "Now let's look at one more thing."}, {"title": "Carbon and Nitrogen Groups .txt", "text": "Let's look at our N. Now normally when we have nitrogen in a molecule or compound that nitrogen has a lone pair of electrons."}, {"title": "Carbon and Nitrogen Groups .txt", "text": "For example, in ammonia."}, {"title": "Carbon and Nitrogen Groups .txt", "text": "And ammonia can take one more H because it has a lone pair of electrons."}, {"title": "Carbon and Nitrogen Groups .txt", "text": "In other words, our nitrogen has the capability of forming not three Covalent bonds, but four Covalent bonds."}, {"title": "Carbon and Nitrogen Groups .txt", "text": "And when our nitrogen takes another h. It forms a positive in charge compound called ammonium."}, {"title": "Henry\u2019s Law Example .txt", "text": "So in this example, we are given one liter of blood at body temperature and we're given Henry's constants for nitrogen and oxygen."}, {"title": "Henry\u2019s Law Example .txt", "text": "You want to find the number of grams of n two and a number of grams of L two resolved within one liter of blood found within our body."}, {"title": "Henry\u2019s Law Example .txt", "text": "Now, as an example, let's take a section of our capillary found within our lung."}, {"title": "Henry\u2019s Law Example .txt", "text": "And let's assume this section contains exactly one liter of blood or one liter of the red molecules."}, {"title": "Henry\u2019s Law Example .txt", "text": "Now, a capillary is simply a very, very small vessel that carries blood."}, {"title": "Henry\u2019s Law Example .txt", "text": "And within a capillary, oxygen and nitrogen can be exchanged with the environment."}, {"title": "Henry\u2019s Law Example .txt", "text": "And we're using lungs because gases are exchanged within our lungs."}, {"title": "Henry\u2019s Law Example .txt", "text": "So we want to find a number of blue molecules and a number of green molecules in terms of grounds found within one liter of this blood."}, {"title": "Henry\u2019s Law Example .txt", "text": "So the first step is to realize that air is composed approximately 79% nitrogen and approximately 21% oxygen."}, {"title": "Henry\u2019s Law Example .txt", "text": "Now, this translates to zero 79 mole fraction nitrogen and 0.2 1 mol fraction of oxygen."}, {"title": "Henry\u2019s Law Example .txt", "text": "So the first step is to use rolled slow."}, {"title": "Henry\u2019s Law Example .txt", "text": "But before we use a roll slow, we must assume that there is dynamic equilibriums between the gas molecules in the space above and the gas molecules dissolved within our blood."}, {"title": "Henry\u2019s Law Example .txt", "text": "So let's make that assumption."}, {"title": "Henry\u2019s Law Example .txt", "text": "Now, we can find the partial pressures of each gas by simply using the formula."}, {"title": "Henry\u2019s Law Example .txt", "text": "Now, before we use the formula, let's let's realize why we're using 760 mmhg."}, {"title": "Henry\u2019s Law Example .txt", "text": "So the total pressure above our system is the air that we're breathing in is the pressure of the air that we're breathing in."}, {"title": "Henry\u2019s Law Example .txt", "text": "And the air we're breathing in is at atmospheric pressure."}, {"title": "Henry\u2019s Law Example .txt", "text": "And atmospheric pressure is one ATM or 760 mercury."}, {"title": "Henry\u2019s Law Example .txt", "text": "So defined partial pressure of oxygen, we simply multiply mole fraction by our total pressure and we get 159.6 mmhg for oxygen and 600.4\nmmhg for nitrogen."}, {"title": "Henry\u2019s Law Example .txt", "text": "So second step is to find the Molarity."}, {"title": "Henry\u2019s Law Example .txt", "text": "We can use these guys, the partial pressures to find the Molarity."}, {"title": "Henry\u2019s Law Example .txt", "text": "Now, Henry's loss states."}, {"title": "Henry\u2019s Law Example .txt", "text": "So we can find the Molarity by simply taking our constant and multiplying it by the partial pressure of the gas."}, {"title": "Henry\u2019s Law Example .txt", "text": "Therefore, we get 1.66\ntimes ten to negative six times 1.59.6 and we get 2.64 times ten to negative four molar for two or moles per liter."}, {"title": "Henry\u2019s Law Example .txt", "text": "Now, we do the same thing, except we change the partial pressure for nitrogen and the concept of nitrogen and we get 5.55 times ten to negative four molar or moles per liter."}, {"title": "Henry\u2019s Law Example .txt", "text": "The third step is to find the moles of oxygen and the moles of nitrogen dissolved within our blood."}, {"title": "Henry\u2019s Law Example .txt", "text": "To find the moles of oxygen, we simply take our Molar concentration, multiply that by one liter of total solution and we get 0.000,264 moles of O two and 0.0055 moles for M two."}, {"title": "Henry\u2019s Law Example .txt", "text": "Finally, we can use the moles, multiplying that by the molecular weight of each respective compound."}, {"title": "Henry\u2019s Law Example .txt", "text": "That will give us the number in grams of each compound resolved within our system."}, {"title": "Henry\u2019s Law Example .txt", "text": "So molecular weight of oxygen, which is 32 grams/mol multiplied by the moles, which is 0.00,134\nmoles, gets us oh, I'm sorry."}, {"title": "Henry\u2019s Law Example .txt", "text": "I made a mistake here."}, {"title": "Henry\u2019s Law Example .txt", "text": "This should be 0.00,264\nmoles."}, {"title": "Henry\u2019s Law Example .txt", "text": "So it's 32 centrist is right."}, {"title": "Henry\u2019s Law Example .txt", "text": "32 times .0,006,264."}, {"title": "Henry\u2019s Law Example .txt", "text": "And that is correct."}, {"title": "Henry\u2019s Law Example .txt", "text": "Okay, so we multiply this out, we get this number of grams and we multiply the molecular weight of nitrogen, 28 grams/mol times 0.0,005,055 moles."}, {"title": "Henry\u2019s Law Example .txt", "text": "And we get 0.14,154 grams of N two."}, {"title": "Henry\u2019s Law Example .txt", "text": "So this amount of grams of O two and this amount of grams of not M two is dissolved within our one liter of blood found in our capillary, in our lung."}, {"title": "Mole Fraction Example .txt", "text": "Molality is simply another way of measuring the concentration of a solution."}, {"title": "Mole Fraction Example .txt", "text": "The symbol for molality is lowercase letter M and the formula is moles of solute over kilograms of solvent."}, {"title": "Mole Fraction Example .txt", "text": "Now let's do an example."}, {"title": "Mole Fraction Example .txt", "text": "Using molality."}, {"title": "Mole Fraction Example .txt", "text": "The question tells us that we have 90 grams of glucose and 200 grams of H 20."}, {"title": "Mole Fraction Example .txt", "text": "And we want to find the molality of the solution."}, {"title": "Mole Fraction Example .txt", "text": "We're basically taking glucose, the salute and water, the solvent."}, {"title": "Mole Fraction Example .txt", "text": "We're mixing it and we want to find the concentration."}, {"title": "Mole Fraction Example .txt", "text": "In terms of molality, the first step is to find the molecular weight of glucose."}, {"title": "Mole Fraction Example .txt", "text": "This will help us find the number of moles of glucose within our solution."}, {"title": "Mole Fraction Example .txt", "text": "The first step is to find the atomic weight of each atom and multiplied by each subscript."}, {"title": "Mole Fraction Example .txt", "text": "So the atomic weight of carbon is 12 grams/mol, the atomic weight of H is 1 gram/mol, and the atomic weight of oxygen is 16 grams/mol."}, {"title": "Mole Fraction Example .txt", "text": "So we multiply six by twelve, add that to twelve times one and add that to six times 16 and we get approximately 180 grams/mol."}, {"title": "Mole Fraction Example .txt", "text": "Now, using this number, we can take our 90 grams of glucose and find the number of moles."}, {"title": "Mole Fraction Example .txt", "text": "90 grams of glucose divided by 180 grams of glucose per mole gets us 0.5\nor one half moles of glucose."}, {"title": "Mole Fraction Example .txt", "text": "That's our number of moles within this solution."}, {"title": "Mole Fraction Example .txt", "text": "The final step is to use the formula for molality."}, {"title": "Mole Fraction Example .txt", "text": "Lowercase M for molality is equal to one half number of moles of salute divided by now notice we're getting 200 grams and molality ditosomality are moles per kilogram."}, {"title": "Mole Fraction Example .txt", "text": "So we have to convert 200 grams to kilogram."}, {"title": "Mole Fraction Example .txt", "text": "We get 0.2\nkilogram of H 20, the solvent, and we get 2.5 molality or moles per kilogram."}, {"title": "Mole Fraction Example .txt", "text": "And that's our final answer."}, {"title": "Henderson-Hasselbach Equation .txt", "text": "So in this lecture we're going to look at something called the Hamilton Hasselbach equation."}, {"title": "Henderson-Hasselbach Equation .txt", "text": "Now this equation has two uses."}, {"title": "Henderson-Hasselbach Equation .txt", "text": "First, we can use it to find the PH of the buffet system."}, {"title": "Henderson-Hasselbach Equation .txt", "text": "And second, we can use it to find the ratio of conjugate base to conjugate acid or the ratio of conjugate acid to conjugate base of our buffet system."}, {"title": "Henderson-Hasselbach Equation .txt", "text": "Now let's see where this equation comes from."}, {"title": "Henderson-Hasselbach Equation .txt", "text": "Let's derive it."}, {"title": "Henderson-Hasselbach Equation .txt", "text": "But first, let's look at the reaction of an acid in an aqueous state with the water molecule in the liquid state."}, {"title": "Henderson-Hasselbach Equation .txt", "text": "Well, what we get is a conjugate base in the acreage state and a conjugate acid in the aqueous states."}, {"title": "Henderson-Hasselbach Equation .txt", "text": "So let's write the equilibrium constant expression for this reaction."}, {"title": "Henderson-Hasselbach Equation .txt", "text": "So we get the acid ionization constant for this acid is equal to the concentration of hydronium times the concentration of the conjugate base."}, {"title": "Henderson-Hasselbach Equation .txt", "text": "These two guys divided by the concentration of the conjugate acid for this guy."}, {"title": "Henderson-Hasselbach Equation .txt", "text": "Now, if you are confused where this expression comes from, check out the link below."}, {"title": "Henderson-Hasselbach Equation .txt", "text": "Now remember, our goal is to find an expression that we can use to solve for the PH."}, {"title": "Henderson-Hasselbach Equation .txt", "text": "So which one of these guys determines PH?"}, {"title": "Henderson-Hasselbach Equation .txt", "text": "Well, it's this guy."}, {"title": "Henderson-Hasselbach Equation .txt", "text": "Remember, PH is equal to negative log of the hydronium concentration."}, {"title": "Henderson-Hasselbach Equation .txt", "text": "So our goal will be to isolate this guy first."}, {"title": "Henderson-Hasselbach Equation .txt", "text": "So let's isolate him."}, {"title": "Henderson-Hasselbach Equation .txt", "text": "We get ka times the concentration of conjugate acid."}, {"title": "Henderson-Hasselbach Equation .txt", "text": "This guy divided by the concentration of conjugate base for this guy equals the hydronium concentration."}, {"title": "Henderson-Hasselbach Equation .txt", "text": "Now our next step is to convert these guys into logs because our PH involves logs."}, {"title": "Henderson-Hasselbach Equation .txt", "text": "So we take the logs of both sides and we get log of base ten of the hydronium concentration of this guy equals log of base ten of this whole guy."}, {"title": "Henderson-Hasselbach Equation .txt", "text": "Now our next goal is to use the laws of logs to convert this guy from this more compact state to a less compact state."}, {"title": "Henderson-Hasselbach Equation .txt", "text": "Now, what we get is the following log of the hydronium concentration."}, {"title": "Henderson-Hasselbach Equation .txt", "text": "This guy is equal to notice inside this log we're multiplying ka times this whole thing, this ratio."}, {"title": "Henderson-Hasselbach Equation .txt", "text": "So another way of expressing this is to use the logs of logs and we get log of ka plus log of this guy."}, {"title": "Henderson-Hasselbach Equation .txt", "text": "So the concentration of the conjugate axis divided by the concentration of conjugate base."}, {"title": "Henderson-Hasselbach Equation .txt", "text": "Now our next step is to basically rewrite this guy in the form of the PH formula."}, {"title": "Henderson-Hasselbach Equation .txt", "text": "We can't say this guy is equal to PH because remember, PH is negative log of this guy."}, {"title": "Henderson-Hasselbach Equation .txt", "text": "So let's take the negative of the whole expression."}, {"title": "Henderson-Hasselbach Equation .txt", "text": "This way we can get our PH."}, {"title": "Henderson-Hasselbach Equation .txt", "text": "So we multiply two by negative one and we get negative this whole thing."}, {"title": "Henderson-Hasselbach Equation .txt", "text": "So negative this equals negative this guy minus this guy."}, {"title": "Henderson-Hasselbach Equation .txt", "text": "So next step is to convert this guy into PH."}, {"title": "Henderson-Hasselbach Equation .txt", "text": "And we get PH is equal to negative of log ka."}, {"title": "Henderson-Hasselbach Equation .txt", "text": "Now notice what happens here whenever we have a negative on the outside of our log."}, {"title": "Henderson-Hasselbach Equation .txt", "text": "That simply means we're taking this guy and raising it to the negative one."}, {"title": "Henderson-Hasselbach Equation .txt", "text": "This is equivalent to saying plus log of this guy to the negative one."}, {"title": "Henderson-Hasselbach Equation .txt", "text": "But this guy to the negative one is simply reciprocating these guys."}, {"title": "Henderson-Hasselbach Equation .txt", "text": "So negative log of this guy is the same as saying positive log of the reciprocal of this guy."}, {"title": "Henderson-Hasselbach Equation .txt", "text": "So the concentration of conjugate base divided by the concentration of conjugate acid."}, {"title": "Henderson-Hasselbach Equation .txt", "text": "So Now, A final formula states we find that PH is equal to."}, {"title": "Henderson-Hasselbach Equation .txt", "text": "Remember, negative log of Ka is simply PKA."}, {"title": "Henderson-Hasselbach Equation .txt", "text": "And we get PH is equal to PKA plus log of the ratio of conjugate base over conjugate acid."}, {"title": "Henderson-Hasselbach Equation .txt", "text": "And this is our Henderson half of block formula."}, {"title": "Henderson-Hasselbach Equation .txt", "text": "Now, if you want to do an example using this formula, check out the link below."}, {"title": "Henderson-Hasselbach Equation .txt", "text": "But remember, this formula can Be used to find Two things."}, {"title": "Henderson-Hasselbach Equation .txt", "text": "So, if You Know the PKA and you know our ratio, you can find the PH."}, {"title": "Henderson-Hasselbach Equation .txt", "text": "If You Know the PH and you know the PKA, you can find the ratio."}, {"title": "Henderson-Hasselbach Equation .txt", "text": "And also actually if you Know the ratio and you know that PH, you can find the PKA."}, {"title": "Lewis Acids and Bases .txt", "text": "So, in this lecture, we're going to examine the interaction between the atomic orbitals of Lewis acids and lowest bases."}, {"title": "Lewis Acids and Bases .txt", "text": "So let's begin by defining what a lowest acid and lowest base is."}, {"title": "Lewis Acids and Bases .txt", "text": "Lewis acids are molecules containing an empty, unfilled atomic orbital, and lowest bases are molecules containing a pair of electrons, bonds, or a filled orbital."}, {"title": "Lewis Acids and Bases .txt", "text": "So let's look at a Lewis acid."}, {"title": "Lewis Acids and Bases .txt", "text": "So, this is one example of a Lewis acid."}, {"title": "Lewis Acids and Bases .txt", "text": "It's a methylcation."}, {"title": "Lewis Acids and Bases .txt", "text": "This methylcation has three SP two hybridized covalent bonds between the C and the HS."}, {"title": "Lewis Acids and Bases .txt", "text": "And it has an empty pur two P orbital given here."}, {"title": "Lewis Acids and Bases .txt", "text": "So it has a positive charge."}, {"title": "Lewis Acids and Bases .txt", "text": "So here's an example of a Lewis base."}, {"title": "Lewis Acids and Bases .txt", "text": "Once again, a Lewis base is a molecule containing a pair of electrons, a pair of non bonding electrons in an orbital."}, {"title": "Lewis Acids and Bases .txt", "text": "So hydrant is an example of a Lewis base because it has two electrons, a pair of non bonding electrons within the one S orbital."}, {"title": "Lewis Acids and Bases .txt", "text": "Now, when the Lewis acid react with the Lewis base, that basically means their atomic orbitals interact."}, {"title": "Lewis Acids and Bases .txt", "text": "They overlap, producing a bond."}, {"title": "Lewis Acids and Bases .txt", "text": "So in this case, when this Lewis acid interacts with this Lewis base, this one S interacts with this two p.\nThese two electrons are donated to this two P orbital."}, {"title": "Lewis Acids and Bases .txt", "text": "Now, as these come closer, this load becomes smaller, this becomes larger so that the overlap is better."}, {"title": "Lewis Acids and Bases .txt", "text": "And we form SP three hybridized bonds."}, {"title": "Lewis Acids and Bases .txt", "text": "So 1234 SP three hybridized bonds."}, {"title": "Lewis Acids and Bases .txt", "text": "And now this carbon and this H share a pair of electrons."}, {"title": "Lewis Acids and Bases .txt", "text": "So let's look at the energy diagram of our interaction of our two lowest acids and bases."}, {"title": "Lewis Acids and Bases .txt", "text": "So, once again, our one S is lowering energy than the two p. That's because this is closer to our nucleus than this orbital is."}, {"title": "Lewis Acids and Bases .txt", "text": "And so this guy will be found lower on the energy level."}, {"title": "Lewis Acids and Bases .txt", "text": "So the y axis in the energy, this will be lower than our two P orbital."}, {"title": "Lewis Acids and Bases .txt", "text": "So the two electrons will come directly from the one S from the Hydride."}, {"title": "Lewis Acids and Bases .txt", "text": "And when they interact, they will form a bonding molecular orbital and an antibounding molecular orbital."}, {"title": "Lewis Acids and Bases .txt", "text": "The two electrons will go into the bonding molecular orbital, forming our SP 30 hybridized molecular orbitals."}, {"title": "Lewis Acids and Bases .txt", "text": "So, though, now let's define what a broncidlaric acid and a broncillary base is."}, {"title": "Lewis Acids and Bases .txt", "text": "A bronzedidlori acid is a molecule that donates an H ion, while a broncillary base is a molecule that accepts an H ion."}, {"title": "Lewis Acids and Bases .txt", "text": "So acid strength of a broncillary acid increases with increasing S character."}, {"title": "Lewis Acids and Bases .txt", "text": "So why is that?"}, {"title": "Lewis Acids and Bases .txt", "text": "Well, to examine that, let's recall one simple concept."}, {"title": "Lewis Acids and Bases .txt", "text": "So, here we have a protons."}, {"title": "Lewis Acids and Bases .txt", "text": "We have a nucleus and protons inside that nucleus."}, {"title": "Lewis Acids and Bases .txt", "text": "And this is our one S orbital, our two S orbital and the two P orbital."}, {"title": "Lewis Acids and Bases .txt", "text": "So recall that as our electron gets closer and closer to our protons in the nucleus, the energy level of the entire atom decreases, so it becomes more stable."}, {"title": "Lewis Acids and Bases .txt", "text": "So the closer our electron is to our nucleus, the more stable that atom is."}, {"title": "Lewis Acids and Bases .txt", "text": "And let's look what happens when an acid, a brothed lauric acid, reacts."}, {"title": "Lewis Acids and Bases .txt", "text": "So, when a brothed Laric acid, reacts, it creates a conjugate base."}, {"title": "Lewis Acids and Bases .txt", "text": "So a brothelary base, and it creates an hion."}, {"title": "Lewis Acids and Bases .txt", "text": "Now, if this has a lot of S character, that means the electron pair here will be found in that S character."}, {"title": "Lewis Acids and Bases .txt", "text": "So, the more S character we have, the closer our electrons are to our nucleus and the more stable our conjugate bases."}, {"title": "Lewis Acids and Bases .txt", "text": "And if we have a stable conjugate base, that means our acid will be more likely to form this conjugate base, and therefore, our acid will be more likely to dissociate."}, {"title": "Lewis Acids and Bases .txt", "text": "And that means our asset will be a stronger acid."}, {"title": "Lewis Acids and Bases .txt", "text": "So, therefore, the more character a broccoliy acid has, the stronger the base it produces."}, {"title": "Lewis Acids and Bases .txt", "text": "And that means the better that acid."}, {"title": "Cahn-Ingold-Prelog Priority System .txt", "text": "So in this lecture, we're going to discuss the Con ingle Prelog priority system."}, {"title": "Cahn-Ingold-Prelog Priority System .txt", "text": "Now, the system is used for either one of two things."}, {"title": "Cahn-Ingold-Prelog Priority System .txt", "text": "It's either used in determining the absolute configuration of your enantomers to either R or S absolute configuration, or it's used to help you rank groups attached to double bonds."}, {"title": "Cahn-Ingold-Prelog Priority System .txt", "text": "So in this lecture, we're going to focus primarily on this usage here."}, {"title": "Cahn-Ingold-Prelog Priority System .txt", "text": "So whenever you're using this system, four important rules must be followed that will help you to get or find the highest priority groups."}, {"title": "Cahn-Ingold-Prelog Priority System .txt", "text": "So let's look at rule number one."}, {"title": "Cahn-Ingold-Prelog Priority System .txt", "text": "So, atom with higher atomic number receives higher priority."}, {"title": "Cahn-Ingold-Prelog Priority System .txt", "text": "So let's see what that means via this example."}, {"title": "Cahn-Ingold-Prelog Priority System .txt", "text": "So here we have a carbon carbon double bond."}, {"title": "Cahn-Ingold-Prelog Priority System .txt", "text": "So let's examine this carbon carbon number one."}, {"title": "Cahn-Ingold-Prelog Priority System .txt", "text": "So carbon number one is attached to two groups."}, {"title": "Cahn-Ingold-Prelog Priority System .txt", "text": "It's either attached to the H or it's attached to the carbon here."}, {"title": "Cahn-Ingold-Prelog Priority System .txt", "text": "So which atom has a higher atomic number?"}, {"title": "Cahn-Ingold-Prelog Priority System .txt", "text": "Well, clearly the carbon has a higher atomic number, and that means this group attached this carbon has a higher priority than this group here."}, {"title": "Cahn-Ingold-Prelog Priority System .txt", "text": "Likewise, let's examine the second carbon."}, {"title": "Cahn-Ingold-Prelog Priority System .txt", "text": "The second carbon of the double bond is also attached to a carbon, and it's also attached to an H.\nWhich one of these two groups has a higher atomic number?"}, {"title": "Cahn-Ingold-Prelog Priority System .txt", "text": "Well, clearly, the carbon has a higher atomic number, and so the carbon wins."}, {"title": "Cahn-Ingold-Prelog Priority System .txt", "text": "And let's label it with an asterisk."}, {"title": "Cahn-Ingold-Prelog Priority System .txt", "text": "So notice that in this compound, our groups with the higher priorities are on the same side of the double bond."}, {"title": "Cahn-Ingold-Prelog Priority System .txt", "text": "And that means this must be a Z isomer."}, {"title": "Cahn-Ingold-Prelog Priority System .txt", "text": "So let's look at rule number two for isotopes."}, {"title": "Cahn-Ingold-Prelog Priority System .txt", "text": "The isotope with a higher atomic weight wins."}, {"title": "Cahn-Ingold-Prelog Priority System .txt", "text": "Remember, two compounds or two atoms are isotopes if they have the same number of protons and electrons, but different number of neutrons."}, {"title": "Cahn-Ingold-Prelog Priority System .txt", "text": "So they differ in atomic weight."}, {"title": "Cahn-Ingold-Prelog Priority System .txt", "text": "So let's look at the following example."}, {"title": "Cahn-Ingold-Prelog Priority System .txt", "text": "Let's suppose we have a carbon carbon double bond."}, {"title": "Cahn-Ingold-Prelog Priority System .txt", "text": "So let's examine this carbon here."}, {"title": "Cahn-Ingold-Prelog Priority System .txt", "text": "This carbon is attached to an H group and also to a D group."}, {"title": "Cahn-Ingold-Prelog Priority System .txt", "text": "D is simply deteriorate."}, {"title": "Cahn-Ingold-Prelog Priority System .txt", "text": "It's the isotope of H. So since D has a higher atomic weight, d must have a higher priority than H.\nSo this group has a higher priority than this group."}, {"title": "Cahn-Ingold-Prelog Priority System .txt", "text": "Likewise, for the second carbon in a double bond, we have the following two groups."}, {"title": "Cahn-Ingold-Prelog Priority System .txt", "text": "Once again, we have the H and we have the D.\nSo our D, the deteriorium, has a higher atomic weight, so it has a higher priority."}, {"title": "Cahn-Ingold-Prelog Priority System .txt", "text": "And now we have an allochene where our two higher priority groups are on opposite sides of the double bond."}, {"title": "Cahn-Ingold-Prelog Priority System .txt", "text": "And that means this must be an Eisomer."}, {"title": "Cahn-Ingold-Prelog Priority System .txt", "text": "So let's look at rule number three."}, {"title": "Cahn-Ingold-Prelog Priority System .txt", "text": "If we have the same atom, if we have a tie between our atoms, we move to the next atom."}, {"title": "Cahn-Ingold-Prelog Priority System .txt", "text": "So let's see exactly what that means."}, {"title": "Cahn-Ingold-Prelog Priority System .txt", "text": "Let's look at the following example."}, {"title": "Cahn-Ingold-Prelog Priority System .txt", "text": "We have a carbon carbon double bond."}, {"title": "Cahn-Ingold-Prelog Priority System .txt", "text": "So let's begin with this carbon, the first carbon in the double bond."}, {"title": "Cahn-Ingold-Prelog Priority System .txt", "text": "So this carbon is attached to a carbon of this side and a carbon on that side."}, {"title": "Cahn-Ingold-Prelog Priority System .txt", "text": "So far, we have a tie."}, {"title": "Cahn-Ingold-Prelog Priority System .txt", "text": "We can't determine the atomic number, so we move on to the next atom."}, {"title": "Cahn-Ingold-Prelog Priority System .txt", "text": "So there is no next atom here."}, {"title": "Cahn-Ingold-Prelog Priority System .txt", "text": "But here we have a following carbon atom."}, {"title": "Cahn-Ingold-Prelog Priority System .txt", "text": "So that means this side wins."}, {"title": "Cahn-Ingold-Prelog Priority System .txt", "text": "It has a higher atomic number and it also has a higher atomic weight."}, {"title": "Cahn-Ingold-Prelog Priority System .txt", "text": "So this side, this group, has a higher priority than the lower group."}, {"title": "Cahn-Ingold-Prelog Priority System .txt", "text": "Likewise, for this carbon, we have the same exact situation."}, {"title": "Cahn-Ingold-Prelog Priority System .txt", "text": "So, once again, as the first example, we have the Z Isomer, because our two higher priority groups are the same size."}, {"title": "Cahn-Ingold-Prelog Priority System .txt", "text": "Finally, let's look at rule number four."}, {"title": "Cahn-Ingold-Prelog Priority System .txt", "text": "A double bond to a carbon is considered as two single bonds."}, {"title": "Cahn-Ingold-Prelog Priority System .txt", "text": "So let's see exactly what that means."}, {"title": "Cahn-Ingold-Prelog Priority System .txt", "text": "Let's suppose we have our double bond here."}, {"title": "Cahn-Ingold-Prelog Priority System .txt", "text": "So a carbon and carbon double bond."}, {"title": "Cahn-Ingold-Prelog Priority System .txt", "text": "We want to examine the groups attached to our first carbon."}, {"title": "Cahn-Ingold-Prelog Priority System .txt", "text": "So here we have a carbon in a carbon."}, {"title": "Cahn-Ingold-Prelog Priority System .txt", "text": "So so far, no one wins."}, {"title": "Cahn-Ingold-Prelog Priority System .txt", "text": "And a carbon and a carbon."}, {"title": "Cahn-Ingold-Prelog Priority System .txt", "text": "So no one wins."}, {"title": "Cahn-Ingold-Prelog Priority System .txt", "text": "But we have a double bond here."}, {"title": "Cahn-Ingold-Prelog Priority System .txt", "text": "And this double bond, according to rule number four, is actually, or actually looks something like this."}, {"title": "Cahn-Ingold-Prelog Priority System .txt", "text": "So every double bond is considered as having two single bonds."}, {"title": "Cahn-Ingold-Prelog Priority System .txt", "text": "So we erase this double bond and we replace one carbon and a second carbon."}, {"title": "Cahn-Ingold-Prelog Priority System .txt", "text": "So two more single covalent bonds."}, {"title": "Cahn-Ingold-Prelog Priority System .txt", "text": "So now this side, this group has a higher atomic weight."}, {"title": "Cahn-Ingold-Prelog Priority System .txt", "text": "And so this group wins, and this group must be the higher priority group."}, {"title": "Cahn-Ingold-Prelog Priority System .txt", "text": "Now, on this side of the carbon, we have two identical methyl groups."}, {"title": "Cahn-Ingold-Prelog Priority System .txt", "text": "So we have carbon and carbon."}, {"title": "Cahn-Ingold-Prelog Priority System .txt", "text": "So no one wins here."}, {"title": "Cahn-Ingold-Prelog Priority System .txt", "text": "And so for this carbon, the in lock pre lock priority system does not work."}, {"title": "Cahn-Ingold-Prelog Priority System .txt", "text": "It yields two groups with the same exact priority."}, {"title": "Cahn-Ingold-Prelog Priority System .txt", "text": "Sorry."}, {"title": "Stability of Alkenes.txt", "text": "So let's suppose we have a certain alky, let's say hexine, for example, and let's write out all different types of isomers of hexine."}, {"title": "Stability of Alkenes.txt", "text": "Now, if we compare the stability of one isomer of hexine to another isomer of exe, we'll see a difference in stability."}, {"title": "Stability of Alkenes.txt", "text": "In other words, some isomers are more stable than other isomers."}, {"title": "Stability of Alkenes.txt", "text": "So in general, why is that?"}, {"title": "Stability of Alkenes.txt", "text": "Why is it that some isomers of alkans are more stable than other isomers of that same alkane?"}, {"title": "Stability of Alkenes.txt", "text": "So we're going to address that question in this lecture."}, {"title": "Stability of Alkenes.txt", "text": "So let's begin by defining change in Enthalpy affirmation."}, {"title": "Stability of Alkenes.txt", "text": "So loosely speaking, enthalpy affirmation is the energy difference between the final product and its constituent elements."}, {"title": "Stability of Alkenes.txt", "text": "In other words, if this value is negative, that means our final products are stable or more stable than the constituent elements."}, {"title": "Stability of Alkenes.txt", "text": "And in fact, the more negative this value is, the more stable our product is."}, {"title": "Stability of Alkenes.txt", "text": "So let's list a few isomers of hexine."}, {"title": "Stability of Alkenes.txt", "text": "So here's list of five different isomers of hexine and each corresponding change in enthalpy of formation."}, {"title": "Stability of Alkenes.txt", "text": "So for example, for this isomer of hexane, we have negative ten kilo cals per mole of change in enthalpy of formation."}, {"title": "Stability of Alkenes.txt", "text": "And we see that as we go from one to five, our values become more and more negative."}, {"title": "Stability of Alkenes.txt", "text": "And five is the most stable isomer and one is the least stabilizomer."}, {"title": "Stability of Alkenes.txt", "text": "So stability increases as we go down from one to five."}, {"title": "Stability of Alkenes.txt", "text": "So why is that?"}, {"title": "Stability of Alkenes.txt", "text": "Why is it that number one is less stable than number five?"}, {"title": "Stability of Alkenes.txt", "text": "So to examine this, let's recall an important detail."}, {"title": "Stability of Alkenes.txt", "text": "Remember, when electrons are found in the s orbital, those electrons are more stable than if the electrons were found in the p orbital."}, {"title": "Stability of Alkenes.txt", "text": "And generally speaking, s character is more stable than p character because of that same concept."}, {"title": "Stability of Alkenes.txt", "text": "So let's examine the different bonds, let's compare one and five and examine different bonds that exist within that molecule."}, {"title": "Stability of Alkenes.txt", "text": "And let's see if we can find where the difference in stability comes from."}, {"title": "Stability of Alkenes.txt", "text": "So let's look at one."}, {"title": "Stability of Alkenes.txt", "text": "So here we have the first isomer."}, {"title": "Stability of Alkenes.txt", "text": "So notice we have a double bond."}, {"title": "Stability of Alkenes.txt", "text": "And within this double bond, the Sigma bond contains SP two, SP two character."}, {"title": "Stability of Alkenes.txt", "text": "Remember, SP two simply means there's 33% S character and 66% P character."}, {"title": "Stability of Alkenes.txt", "text": "SP three means there's only 25% S character and 75% P character."}, {"title": "Stability of Alkenes.txt", "text": "So SP two bonds are more stable than SP three bonds because SP two bonds contain more S character."}, {"title": "Stability of Alkenes.txt", "text": "So this Sigma bond within the double bond contains SP two SP two character."}, {"title": "Stability of Alkenes.txt", "text": "This bond, this covalent bond has SP two SP three character."}, {"title": "Stability of Alkenes.txt", "text": "And each of these three covalent bonds has SP three SP three character each."}, {"title": "Stability of Alkenes.txt", "text": "So we have three SP three SP three bonds."}, {"title": "Stability of Alkenes.txt", "text": "We have one SP two SP two bond, and we have one SP two SP three bonds."}, {"title": "Stability of Alkenes.txt", "text": "So now let's compare the bonds within compound pi within itemer number five."}, {"title": "Stability of Alkenes.txt", "text": "So once again, we have that same exact SP two SP two bond like we have here and we have 1234 SP three SP two bonds."}, {"title": "Stability of Alkenes.txt", "text": "So notice we have more stable bonds within this compound than this compound because SP two is more stable than SP three."}, {"title": "Stability of Alkenes.txt", "text": "Here, we only have one SP two SP three bond and the rest are SP three SP threes, while here, all four bonds are SP three SP two bonds."}, {"title": "Stability of Alkenes.txt", "text": "So in other words, electrons are more stable in the s orbitals."}, {"title": "Stability of Alkenes.txt", "text": "Thus, the more S character in a bond, the more stable that bond."}, {"title": "Stability of Alkenes.txt", "text": "And alkines are more stable when they have bonds with a lot of S character."}, {"title": "Stability of Alkenes.txt", "text": "So in other words, the reason that we become more stable as we go down the list is because as we go down the list our bonds increase in strength."}, {"title": "Stability of Alkenes.txt", "text": "Here we have our strongest bonds because we have most s character or more s characters."}, {"title": "Stability of Alkenes.txt", "text": "And here we have the least stable compound or isomer because we have the least amount of S character."}, {"title": "Chemical Equilibrium and Equilibirium Constant .txt", "text": "Today we're going to talk about the concept of chemical equilibrium or dynamic equilibrium."}, {"title": "Chemical Equilibrium and Equilibirium Constant .txt", "text": "Now, let's look at the following hypothetical reversible first order elementary reaction in which x converts to Y in a single step."}, {"title": "Chemical Equilibrium and Equilibirium Constant .txt", "text": "Elementary simply means that we can use the coefficients of X and Y to produce the rate law."}, {"title": "Chemical Equilibrium and Equilibirium Constant .txt", "text": "So let's begin at time equals zero."}, {"title": "Chemical Equilibrium and Equilibirium Constant .txt", "text": "The concentration of our reactants is very high and the concentration of our product is very low."}, {"title": "Chemical Equilibrium and Equilibirium Constant .txt", "text": "It's actually zero."}, {"title": "Chemical Equilibrium and Equilibirium Constant .txt", "text": "So at times zero before our reaction even occurred."}, {"title": "Chemical Equilibrium and Equilibirium Constant .txt", "text": "We don't have any of our products yet the products haven't formed, so our Y is zero."}, {"title": "Chemical Equilibrium and Equilibirium Constant .txt", "text": "Now, our X, the concentration of X of our reactants is at its maximum because none of this guy has converted to Y yet."}, {"title": "Chemical Equilibrium and Equilibirium Constant .txt", "text": "However, as the reaction begins to proceed, the concentration of X begins to decrease, while the concentration of Y begins to increase because some of this X is converting or becoming Y."}, {"title": "Chemical Equilibrium and Equilibirium Constant .txt", "text": "Eventually a point is reached in which the concentration of the reactants of X and the concentration of the products Y does not change."}, {"title": "Chemical Equilibrium and Equilibirium Constant .txt", "text": "And this is known as chemical equilibrium."}, {"title": "Chemical Equilibrium and Equilibirium Constant .txt", "text": "This is the point of greatest entropy."}, {"title": "Chemical Equilibrium and Equilibirium Constant .txt", "text": "In other words, our entropy of our system is at its highest at equilibrium."}, {"title": "Chemical Equilibrium and Equilibirium Constant .txt", "text": "Now, let's look at the rates of the reactions, the four reaction and the reverse reaction at each point."}, {"title": "Chemical Equilibrium and Equilibirium Constant .txt", "text": "Let's go back here."}, {"title": "Chemical Equilibrium and Equilibirium Constant .txt", "text": "Now, at this point, what's the rate of our forward reaction of X to Y?"}, {"title": "Chemical Equilibrium and Equilibirium Constant .txt", "text": "Well, our rate is determined by our rate constant as well as the concentration of X."}, {"title": "Chemical Equilibrium and Equilibirium Constant .txt", "text": "And because our constant K stays the same at the same temperature going this way, that means our rate is strictly dependent on our concentration."}, {"title": "Chemical Equilibrium and Equilibirium Constant .txt", "text": "And because we said our concentration is at its maximum at the beginning at time equals zero, that means our rate going this way forward of X converting to Y is at its highest."}, {"title": "Chemical Equilibrium and Equilibirium Constant .txt", "text": "What about the reverse rate of going from Y to X?"}, {"title": "Chemical Equilibrium and Equilibirium Constant .txt", "text": "Well, at the beginning we said we don't have any of the Y, our Y or concentration of our product is zero."}, {"title": "Chemical Equilibrium and Equilibirium Constant .txt", "text": "And that means since this guy is zero for the reverse reaction, that means our rate going backwards is zero."}, {"title": "Chemical Equilibrium and Equilibirium Constant .txt", "text": "And that makes sense because if none of the Y has formed yet, that means none of the Y can convert back to X."}, {"title": "Chemical Equilibrium and Equilibirium Constant .txt", "text": "So let's go to this point somewhere in between our initial and our final."}, {"title": "Chemical Equilibrium and Equilibirium Constant .txt", "text": "Well, somewhere here, our rate begins to decrease going this way."}, {"title": "Chemical Equilibrium and Equilibirium Constant .txt", "text": "In other words, because our concentration of X begins to slowly diminish, this guy begins to get smaller."}, {"title": "Chemical Equilibrium and Equilibirium Constant .txt", "text": "And so, since this guy remains the same throughout the experiment going this way, that means our rate also begins to diminish going from X to Y."}, {"title": "Chemical Equilibrium and Equilibirium Constant .txt", "text": "How about going from Y to X?"}, {"title": "Chemical Equilibrium and Equilibirium Constant .txt", "text": "Well, going from Y to X, our concentration of that product begins to increase."}, {"title": "Chemical Equilibrium and Equilibirium Constant .txt", "text": "And that means as the reaction is going this way, we're getting more of y."}, {"title": "Chemical Equilibrium and Equilibirium Constant .txt", "text": "That means our Y, our rate law for going from the products to reactants begins to increase the rate of reaction, rate of reverse reaction."}, {"title": "Chemical Equilibrium and Equilibirium Constant .txt", "text": "That's because the concentration of Y begins to increase."}, {"title": "Chemical Equilibrium and Equilibirium Constant .txt", "text": "Eventually, the concentration of this guy and this guy at equilibrium will be exactly constant."}, {"title": "Chemical Equilibrium and Equilibirium Constant .txt", "text": "They won't be the same, although they could be the same, but they will be constant."}, {"title": "Chemical Equilibrium and Equilibirium Constant .txt", "text": "The concentration of x will not change and the concentration of Y will also not change."}, {"title": "Chemical Equilibrium and Equilibirium Constant .txt", "text": "And that means our rate of the reverse reaction this way and the rate of the four reaction known this way will be the same."}, {"title": "Chemical Equilibrium and Equilibirium Constant .txt", "text": "Now, once again, it's important to understand that the concentration of x and Y in equilibrium will not be the same."}, {"title": "Chemical Equilibrium and Equilibirium Constant .txt", "text": "They could be the same, but it's not necessary for them to be the same."}, {"title": "Chemical Equilibrium and Equilibirium Constant .txt", "text": "The reason that their rates are equal is because the K constant going this way and the K constant for the reverse reaction are different values."}, {"title": "Chemical Equilibrium and Equilibirium Constant .txt", "text": "And so the rates are equal even though the concentrations might not be equal because the K's balance the rates out."}, {"title": "Chemical Equilibrium and Equilibirium Constant .txt", "text": "Now, once again, it's important to understand that entropy at this point is at its highest because entropy defines the most probable state and equilibrium is the most probable state."}, {"title": "Chemical Equilibrium and Equilibirium Constant .txt", "text": "Now, it's also important to understand that at this point it's dynamic equilibrium."}, {"title": "Chemical Equilibrium and Equilibirium Constant .txt", "text": "In other words, the reactions are still occurring."}, {"title": "Chemical Equilibrium and Equilibirium Constant .txt", "text": "X is still being converted to Y and y is still being converted to x."}, {"title": "Chemical Equilibrium and Equilibirium Constant .txt", "text": "It's just because the two rates are equal, the concentrations remain the same."}, {"title": "Chemical Equilibrium and Equilibirium Constant .txt", "text": "So even though it seems like the reactions have stopped occurring, x is not going to Y and Y is not going to x."}, {"title": "Chemical Equilibrium and Equilibirium Constant .txt", "text": "That's not true."}, {"title": "Chemical Equilibrium and Equilibirium Constant .txt", "text": "Reactions forward and backward are still occurring."}, {"title": "Chemical Equilibrium and Equilibirium Constant .txt", "text": "It's just they're occurring at the same rate."}, {"title": "Chemical Equilibrium and Equilibirium Constant .txt", "text": "And that's exactly why the concentrations are remaining the same."}, {"title": "Chemical Equilibrium and Equilibirium Constant .txt", "text": "Now suppose, for example, if I added more x, if I add more x, I would change my concentration of x."}, {"title": "Chemical Equilibrium and Equilibirium Constant .txt", "text": "And that means for a few seconds or for some time, my concentration of x would change and this would shift equilibrium this way, causing x to be converted to Y at a faster rate than y converted to x."}, {"title": "Chemical Equilibrium and Equilibirium Constant .txt", "text": "And that's called leisurely air principle and we'll talk about that in another lecture."}, {"title": "Chemical Equilibrium and Equilibirium Constant .txt", "text": "So now let's suppose we have the following elementary reaction in which our reactants x and y convert to our product z and W. Now, A-B-C and D are the coefficients that represent the moles of each respective atom."}, {"title": "Chemical Equilibrium and Equilibirium Constant .txt", "text": "Now let's suppose our reaction is a dynamic equilibrium."}, {"title": "Chemical Equilibrium and Equilibirium Constant .txt", "text": "And what that basically means once again is that the rates at which x and Y are converting to z and W is the same as the rate at which z and w is converting to x and Y."}, {"title": "Chemical Equilibrium and Equilibirium Constant .txt", "text": "Now, once again, we're making an assumption that this is elementary reaction."}, {"title": "Chemical Equilibrium and Equilibirium Constant .txt", "text": "So that means we can write the rate law for each reaction going this way and going that way by simply using the coefficient ADC and d.\nSo let's do exactly that."}, {"title": "Chemical Equilibrium and Equilibirium Constant .txt", "text": "So the rate of our four reaction is equal to the constant for going this way."}, {"title": "Chemical Equilibrium and Equilibirium Constant .txt", "text": "K one times the concentration of A to the A power times the concentration of y to the b power, the coefficients."}, {"title": "Chemical Equilibrium and Equilibirium Constant .txt", "text": "And this equals the rate of the reverse reaction, the backwards reaction z and w converting back to x and y."}, {"title": "Chemical Equilibrium and Equilibirium Constant .txt", "text": "And this equals k minus one, which is a different constant than this constant."}, {"title": "Chemical Equilibrium and Equilibirium Constant .txt", "text": "Remember, the two constants going this way and this way are different times the concentration of z to the c coefficient or exponent times the concentration of w to the d power."}, {"title": "Chemical Equilibrium and Equilibirium Constant .txt", "text": "Now this guy is equal to this guy because we're a dynamic equilibrium."}, {"title": "Chemical Equilibrium and Equilibirium Constant .txt", "text": "And the only reason we are able to write the rate laws like this using the coefficients is because this is an elementary reaction."}, {"title": "Chemical Equilibrium and Equilibirium Constant .txt", "text": "So now let's bring all the constant to one side and everything else the concentrations to this side."}, {"title": "Chemical Equilibrium and Equilibirium Constant .txt", "text": "So we get the following."}, {"title": "Chemical Equilibrium and Equilibirium Constant .txt", "text": "K one divided by k minus one equals this guy divided by this guy."}, {"title": "Chemical Equilibrium and Equilibirium Constant .txt", "text": "Now notice that these two guys are constants."}, {"title": "Chemical Equilibrium and Equilibirium Constant .txt", "text": "They're the same or they don't change at the same temperature."}, {"title": "Chemical Equilibrium and Equilibirium Constant .txt", "text": "And that means we can represent this guy as another constant, namely K. Now this K is known as the equilibrium constant."}, {"title": "Chemical Equilibrium and Equilibirium Constant .txt", "text": "And the relationship between our K, the equilibrium constant."}, {"title": "Chemical Equilibrium and Equilibirium Constant .txt", "text": "And the chemical equation above is known as the law of mass action."}, {"title": "Chemical Equilibrium and Equilibirium Constant .txt", "text": "So what's the meaning of K?"}, {"title": "Chemical Equilibrium and Equilibirium Constant .txt", "text": "Well, K is simply the ratio of the concentration of products and the concentration of reactants at equilibrium when the Navy equilibrium has been established."}, {"title": "Chemical Equilibrium and Equilibirium Constant .txt", "text": "And what K does is it tells us how far the reaction proceeded at equilibrium."}, {"title": "Chemical Equilibrium and Equilibirium Constant .txt", "text": "In other words, we can have three situations."}, {"title": "Chemical Equilibrium and Equilibirium Constant .txt", "text": "K can either be greater than one and if K is greater than one, that means at equilibrium we have more products than reactants."}, {"title": "Chemical Equilibrium and Equilibirium Constant .txt", "text": "And that means our reaction is a product favored, it's spontaneous going this way."}, {"title": "Chemical Equilibrium and Equilibirium Constant .txt", "text": "Now, if K equals one, that means at equilibrium our concentration of products is the same as the concentration of reactants."}, {"title": "Chemical Equilibrium and Equilibirium Constant .txt", "text": "Now, if K is less than one, that means this denominator is larger than our enumerator."}, {"title": "Chemical Equilibrium and Equilibirium Constant .txt", "text": "And that means we have more concentration of reactants of these guys at equilibrium than of our products than these guys."}, {"title": "Chemical Equilibrium and Equilibirium Constant .txt", "text": "And that means our reaction is not product favorite, it's not spontaneous, in fact it's reactant favorite."}, {"title": "Chemical Equilibrium and Equilibirium Constant .txt", "text": "This reaction is spontaneous, but this reaction isn't if our K is less than one."}, {"title": "Chemical Equilibrium and Equilibirium Constant .txt", "text": "And that's the meaning of K. Now, a few more important things that I want to mention about equilibrium constants."}, {"title": "Chemical Equilibrium and Equilibirium Constant .txt", "text": "Now an equilibrium constant is unitless."}, {"title": "Chemical Equilibrium and Equilibirium Constant .txt", "text": "And that's because we're dividing concentration by concentration."}, {"title": "Chemical Equilibrium and Equilibirium Constant .txt", "text": "So our units at the end will cancel out."}, {"title": "Chemical Equilibrium and Equilibirium Constant .txt", "text": "Now, our equilibrium constant depends strictly on temperature."}, {"title": "Chemical Equilibrium and Equilibirium Constant .txt", "text": "And that's because our constant is actually a rate constant divided by a rate constant."}, {"title": "Chemical Equilibrium and Equilibirium Constant .txt", "text": "So it's the ratio of the rate constant going this way to the rate constant going in the reverse direction."}, {"title": "Chemical Equilibrium and Equilibirium Constant .txt", "text": "And because these guys are dependent only on temperature, these guys also depend upon temperature."}, {"title": "Chemical Equilibrium and Equilibirium Constant .txt", "text": "It does not depend on the concentration."}, {"title": "Chemical Equilibrium and Equilibirium Constant .txt", "text": "Now note there is a big difference between equilibrium constant and chemical equilibrium."}, {"title": "Chemical Equilibrium and Equilibirium Constant .txt", "text": "Although the two things are related, they're two different separate ideas."}, {"title": "Chemical Equilibrium and Equilibirium Constant .txt", "text": "Once again, equilibrium constant is a ratio of products to reactants, and it depends on temperature."}, {"title": "Chemical Equilibrium and Equilibirium Constant .txt", "text": "While chemical equilibrium refers to a condition, a system."}, {"title": "Chemical Equilibrium and Equilibirium Constant .txt", "text": "And if we add, for example, more reactants to our system now our chemical equilibrium is shifted to the right, more reactants will be produced."}, {"title": "Chemical Equilibrium and Equilibirium Constant .txt", "text": "And that's because of Washacliere's principle."}, {"title": "Chemical Equilibrium and Equilibirium Constant .txt", "text": "We'll discuss that in a bit."}, {"title": "Chemical Equilibrium and Equilibirium Constant .txt", "text": "But remember to have this distinction between equilibrium constant and chemical equilibrium."}, {"title": "Chemical Equilibrium and Equilibirium Constant .txt", "text": "There are different things."}, {"title": "Chemical Equilibrium and Equilibirium Constant .txt", "text": "Last thing I want to mention is about this expression, this chemical equilibrium expression."}, {"title": "Chemical Equilibrium and Equilibirium Constant .txt", "text": "Now, notice we included every single reactant product."}, {"title": "Chemical Equilibrium and Equilibirium Constant .txt", "text": "And that's because we assume that X-Y-Z and W were either in the aqueous state or the gas state."}, {"title": "Chemical Equilibrium and Equilibirium Constant .txt", "text": "Now only aqueous or gas molecules are included or expressed in our final expression."}, {"title": "Chemical Equilibrium and Equilibirium Constant .txt", "text": "Solid molecules and liquid molecules are not included in our expression."}, {"title": "Chemical Equilibrium and Equilibirium Constant .txt", "text": "And that's because their density stays the same throughout our experiment."}, {"title": "Chemical Equilibrium and Equilibirium Constant .txt", "text": "And so they really have no effect on our equilibrium constant or chemical equilibrium."}, {"title": "Neuron Cells Part II .txt", "text": "Now, any given time during the rest of the potential, our concentration on the outside is lasted on the inside."}, {"title": "Neuron Cells Part II .txt", "text": "So let's say our outside is 0.003 molar, and on the inside is 0.135\nmolar."}, {"title": "Neuron Cells Part II .txt", "text": "So how would we find the cell voltage due to the potassium ions?"}, {"title": "Neuron Cells Part II .txt", "text": "Will we use the Nurse equation?"}, {"title": "Neuron Cells Part II .txt", "text": "What this equation says is our cell voltage at any given concentration is equal to our standard cell voltage."}, {"title": "Neuron Cells Part II .txt", "text": "But this guy is zero."}, {"title": "Neuron Cells Part II .txt", "text": "We just said that the cell voltage of this reaction and this reaction are equal but opposite."}, {"title": "Neuron Cells Part II .txt", "text": "So when you add them, this guy goes to zero."}, {"title": "Neuron Cells Part II .txt", "text": "That means our cell voltage is just simply this whole guy."}, {"title": "Neuron Cells Part II .txt", "text": "Where gas constant T is our temperature, n is the Mozzo electrons, epic Faradays constant."}, {"title": "Neuron Cells Part II .txt", "text": "And Q is our expression."}, {"title": "Neuron Cells Part II .txt", "text": "Now, let's look at Q first."}, {"title": "Neuron Cells Part II .txt", "text": "What is Q?"}, {"title": "Neuron Cells Part II .txt", "text": "Well, Q is the concentration of products divided by the concentration of reactants, right?"}, {"title": "Neuron Cells Part II .txt", "text": "And our products is this guy, it's 0.3 molar, our 0.3 molar."}, {"title": "Neuron Cells Part II .txt", "text": "Sorry."}, {"title": "Neuron Cells Part II .txt", "text": "And this guy is zero point 13 five molar."}, {"title": "Neuron Cells Part II .txt", "text": "So our Q is 0.3\nover zero point 13 five."}, {"title": "Neuron Cells Part II .txt", "text": "The M cancel out."}, {"title": "Neuron Cells Part II .txt", "text": "Now, our T is our temperature of our body."}, {"title": "Neuron Cells Part II .txt", "text": "It's not 25 degrees Celsius, it's 37 degrees Celsius."}, {"title": "Neuron Cells Part II .txt", "text": "So we have 37 to 273, and we get 310."}, {"title": "Neuron Cells Part II .txt", "text": "So it's 310 right here."}, {"title": "Neuron Cells Part II .txt", "text": "This is our gas constant."}, {"title": "Neuron Cells Part II .txt", "text": "It's just a constant 8.3, 114."}, {"title": "Neuron Cells Part II .txt", "text": "Our fahrenheit is constant."}, {"title": "Neuron Cells Part II .txt", "text": "So what is N is the moles of electrons produced per potassium or a mole of potassium."}, {"title": "Neuron Cells Part II .txt", "text": "So notice that our mole here is one."}, {"title": "Neuron Cells Part II .txt", "text": "It's a ratio of one to one."}, {"title": "Neuron Cells Part II .txt", "text": "That means we have 1 mol of electron."}, {"title": "Neuron Cells Part II .txt", "text": "So number one goes for N.\nWe plug these guys into the calculator."}, {"title": "Neuron Cells Part II .txt", "text": "Notice that natural log of a number smaller than one gives you a negative number."}, {"title": "Neuron Cells Part II .txt", "text": "So the negative is becoming positive."}, {"title": "Neuron Cells Part II .txt", "text": "And this is our final cell voltage, zero point 102 volts."}, {"title": "Neuron Cells Part II .txt", "text": "So then we do the same exact thing for calcium, for sodium, and for chloride."}, {"title": "Neuron Cells Part II .txt", "text": "Add all the guys up and we should get our final resting electrical potential to sell."}, {"title": "Neuron Cells Part II .txt", "text": "Now, I want to talk more about the meaning of this number."}, {"title": "Neuron Cells Part II .txt", "text": "What is meant by this number?"}, {"title": "Neuron Cells Part II .txt", "text": "Remember, we have the electrochemical gradient of our cell."}, {"title": "Neuron Cells Part II .txt", "text": "And this is the gradient due to the concentration of ions and due to charge."}, {"title": "Neuron Cells Part II .txt", "text": "So it's the chemical gradient and electrical gradient or voltage gradient."}, {"title": "Neuron Cells Part II .txt", "text": "And these guys are opposite of each other."}, {"title": "Neuron Cells Part II .txt", "text": "In other words, notice that our potassium ion, there is a larger concentration on the inside than outside."}, {"title": "Neuron Cells Part II .txt", "text": "And that means these guys will tend to move down their chemical gradients, right?"}, {"title": "Neuron Cells Part II .txt", "text": "Because there are more of these guys on the outside."}, {"title": "Neuron Cells Part II .txt", "text": "So equilibrium will want to establish and these guys will want to move to the outside down their chemical gradient."}, {"title": "Neuron Cells Part II .txt", "text": "Now, electrical gradient is the opposite of that."}, {"title": "Neuron Cells Part II .txt", "text": "Because electrons travel this way, electrons will want to travel to the place where there is more positive charge."}, {"title": "Neuron Cells Part II .txt", "text": "That means it's opposite."}, {"title": "Neuron Cells Part II .txt", "text": "Now, what this number means is that when our electrical gradient and our chemical gradient equal to this number, when they're both this number, that means equilibrium will be established between the potassium ions and the same number of potassium ions will be going in as they will be coming out, right?"}, {"title": "Neuron Cells Part II .txt", "text": "So the rates will equal, and that's what this number means."}, {"title": "Neuron Cells Part II .txt", "text": "So actually, our electrical potential should be negative of this because they're opposite of each other."}, {"title": "Neuron Cells Part II .txt", "text": "They have the same magnitude but different signs."}, {"title": "Neuron Cells Part II .txt", "text": "So our electrical potential for a potassium is negative."}, {"title": "Neuron Cells Part II .txt", "text": "0.12 volts."}, {"title": "Diffusion of Gas and Graham\u2019s Law .txt", "text": "So we already spoke about a process called effusion which is the movement of gas molecules from a high pressure to a low pressure via a very small hole."}, {"title": "Diffusion of Gas and Graham\u2019s Law .txt", "text": "And we said that we can find the rates at which gas molecules effuse via something called Grams law which is given right down here."}, {"title": "Diffusion of Gas and Graham\u2019s Law .txt", "text": "And Grams law states that rate rate of gas molecule one over rate of gas molecule two is equal to the square root of mass of two divided by the square root of mass of one."}, {"title": "Diffusion of Gas and Graham\u2019s Law .txt", "text": "And what this says is that the lighter the molecule, the faster its rate or the higher its rate."}, {"title": "Diffusion of Gas and Graham\u2019s Law .txt", "text": "Now we're going to talk about something called diffusion."}, {"title": "Diffusion of Gas and Graham\u2019s Law .txt", "text": "Diffusion is the movement or the flux of one type of gas molecule into another gas or an empty space."}, {"title": "Diffusion of Gas and Graham\u2019s Law .txt", "text": "And now we can use grammar's law to approximate the rates of diffusion."}, {"title": "Diffusion of Gas and Graham\u2019s Law .txt", "text": "Now, the reason that we approximate is because of something called mean free path."}, {"title": "Diffusion of Gas and Graham\u2019s Law .txt", "text": "Now, the average or the mean free path of a gas molecule is the distance it travels between any two collisions."}, {"title": "Diffusion of Gas and Graham\u2019s Law .txt", "text": "So let's look at this system here."}, {"title": "Diffusion of Gas and Graham\u2019s Law .txt", "text": "In this system we have a square and we have a bunch of red molecules."}, {"title": "Diffusion of Gas and Graham\u2019s Law .txt", "text": "We have one green molecule."}, {"title": "Diffusion of Gas and Graham\u2019s Law .txt", "text": "Suppose this green molecule wants to go from this corner to this corner."}, {"title": "Diffusion of Gas and Graham\u2019s Law .txt", "text": "Now, the best way would be to go directly across from this point to this point."}, {"title": "Diffusion of Gas and Graham\u2019s Law .txt", "text": "But notice that we have a bunch of red molecules in the way."}, {"title": "Diffusion of Gas and Graham\u2019s Law .txt", "text": "So this guy will have to push its way to the other side."}, {"title": "Diffusion of Gas and Graham\u2019s Law .txt", "text": "And by pushing, I mean colliding."}, {"title": "Diffusion of Gas and Graham\u2019s Law .txt", "text": "So it's going to travel some distance A, then distance B, then CDEF, and finally G.\nSo each time it collides and it bounces off."}, {"title": "Diffusion of Gas and Graham\u2019s Law .txt", "text": "Now, to find the mean free path or the average distance between a two collisions, I simply add up all the distances up and divide by the number of collisions."}, {"title": "Diffusion of Gas and Graham\u2019s Law .txt", "text": "And that's my mean free path."}, {"title": "Diffusion of Gas and Graham\u2019s Law .txt", "text": "Now, because of this, we can use Grams law to approximate diffusion and we'll see why in a second."}, {"title": "Diffusion of Gas and Graham\u2019s Law .txt", "text": "So let's look at an illustration of diffusion."}, {"title": "Diffusion of Gas and Graham\u2019s Law .txt", "text": "Suppose I have a cylindrical tube and I have two claps."}, {"title": "Diffusion of Gas and Graham\u2019s Law .txt", "text": "Suppose I take this clap, I soak it into ammonia NH three and plug it up."}, {"title": "Diffusion of Gas and Graham\u2019s Law .txt", "text": "Suppose I take this cloth, I soak it up in hydrochloric acid and then plug it up as well."}, {"title": "Diffusion of Gas and Graham\u2019s Law .txt", "text": "So it's plugged up on both sides and I have air molecules in the middle."}, {"title": "Diffusion of Gas and Graham\u2019s Law .txt", "text": "So orange guys are air molecules, green guys armonia molecules and red guys are hydrochloric molecules."}, {"title": "Diffusion of Gas and Graham\u2019s Law .txt", "text": "So what will happen?"}, {"title": "Diffusion of Gas and Graham\u2019s Law .txt", "text": "Well, some of these guys will evaporate and some of these guys will evaporate and they will begin moving."}, {"title": "Diffusion of Gas and Graham\u2019s Law .txt", "text": "But they won't move directly from this point to this point."}, {"title": "Diffusion of Gas and Graham\u2019s Law .txt", "text": "They will move via a crooked path because of something called the mean free path because there are air molecules present."}, {"title": "Diffusion of Gas and Graham\u2019s Law .txt", "text": "And these air molecules will create collisions."}, {"title": "Diffusion of Gas and Graham\u2019s Law .txt", "text": "And this green molecule, for example, will first collide with this guy, then move here, close the wall, then collide with this guy, and so on until it gets to some point here."}, {"title": "Diffusion of Gas and Graham\u2019s Law .txt", "text": "Now, when the green guy reaches the red guy, something will happen."}, {"title": "Diffusion of Gas and Graham\u2019s Law .txt", "text": "Well, the reaction is as follows."}, {"title": "Diffusion of Gas and Graham\u2019s Law .txt", "text": "The green guy reacts with the red guy, or ammonia reacts with hydrochloric acid."}, {"title": "Diffusion of Gas and Graham\u2019s Law .txt", "text": "In a gas station to form a precipitate, it forms a solid."}, {"title": "Diffusion of Gas and Graham\u2019s Law .txt", "text": "So when these guys meet, at whatever point they will meet, they will form a wall or a solid wall."}, {"title": "Diffusion of Gas and Graham\u2019s Law .txt", "text": "The precipitate."}, {"title": "Diffusion of Gas and Graham\u2019s Law .txt", "text": "And my question is, at which point will the wall lie?"}, {"title": "Diffusion of Gas and Graham\u2019s Law .txt", "text": "Will it be in the middle?"}, {"title": "Diffusion of Gas and Graham\u2019s Law .txt", "text": "Will it be on this side?"}, {"title": "Diffusion of Gas and Graham\u2019s Law .txt", "text": "Or closer to hydrochloric acid?"}, {"title": "Diffusion of Gas and Graham\u2019s Law .txt", "text": "So, we can use Grounds law to approximate the position of this wall of solid."}, {"title": "Diffusion of Gas and Graham\u2019s Law .txt", "text": "And the way we do it is the following."}, {"title": "Diffusion of Gas and Graham\u2019s Law .txt", "text": "So rate one over rate two equals square root of mass of two divided by the square root of mass of one equal."}, {"title": "Diffusion of Gas and Graham\u2019s Law .txt", "text": "So what's the molecular weight or mass of my ammonia?"}, {"title": "Diffusion of Gas and Graham\u2019s Law .txt", "text": "Well, it's 14 plus three gives us 17 on the bottom."}, {"title": "Diffusion of Gas and Graham\u2019s Law .txt", "text": "What about this guy?"}, {"title": "Diffusion of Gas and Graham\u2019s Law .txt", "text": "Well, one plus 35.5 gives us 36.5."}, {"title": "Diffusion of Gas and Graham\u2019s Law .txt", "text": "So 36.5 on top."}, {"title": "Diffusion of Gas and Graham\u2019s Law .txt", "text": "We plug this into our calculator, and we get 1.5."}, {"title": "Diffusion of Gas and Graham\u2019s Law .txt", "text": "So rate of molecule one is 1.5 times larger or faster than rate of two, because two is heavier."}, {"title": "Diffusion of Gas and Graham\u2019s Law .txt", "text": "So it's not going to travel with the same velocity."}, {"title": "Diffusion of Gas and Graham\u2019s Law .txt", "text": "Velocity will be smaller."}, {"title": "Diffusion of Gas and Graham\u2019s Law .txt", "text": "Remember, we're assuming constant temperature."}, {"title": "Diffusion of Gas and Graham\u2019s Law .txt", "text": "So kinetic energies or average kinetic energies are equal."}, {"title": "Diffusion of Gas and Graham\u2019s Law .txt", "text": "So if they're equal and masses are different, then velocities are also different."}, {"title": "Diffusion of Gas and Graham\u2019s Law .txt", "text": "So this guy will travel 1.5 times this way than this guy."}, {"title": "Naming of Alkenes.txt", "text": "So naming alkines is very similar to naming alkanes, but a few differences do exist."}, {"title": "Naming of Alkenes.txt", "text": "So let's look at a few important rules that we have to use whenever we're naming alkanes."}, {"title": "Naming of Alkenes.txt", "text": "Rule number one, find the longest possible carbon chain containing all the double bonds."}, {"title": "Naming of Alkenes.txt", "text": "Rule number two, the lowest possible number value is given to the double bonds."}, {"title": "Naming of Alkenes.txt", "text": "Rule number three, if molecules contain more than one double bond, we give it a specific name."}, {"title": "Naming of Alkenes.txt", "text": "For example two double bonds, we name it a dying three double bonds, we name it a triangle."}, {"title": "Naming of Alkenes.txt", "text": "And rule number four, ring compounds containing double bonds are called cycloalkings."}, {"title": "Naming of Alkenes.txt", "text": "So here we have six examples."}, {"title": "Naming of Alkenes.txt", "text": "So let's look at example A, in which we're going to name our alkane."}, {"title": "Naming of Alkenes.txt", "text": "So our first and second step tells us that we have to find the longest possible carbon backbone and we have to assign our double bond the lowest possible number value."}, {"title": "Naming of Alkenes.txt", "text": "So that means we have to begin on this end."}, {"title": "Naming of Alkenes.txt", "text": "So carbon number one, carbon number two, carbon number three, carbon number four."}, {"title": "Naming of Alkenes.txt", "text": "Notice in this case we have a four carbon backbone and our double bond has a one."}, {"title": "Naming of Alkenes.txt", "text": "It gets assigned a number one because our double bond begins on carbon one."}, {"title": "Naming of Alkenes.txt", "text": "If we begin number eight, our backbone, from this end, our carbon double bond will get a three."}, {"title": "Naming of Alkenes.txt", "text": "And since we want the lowest possible number value according to step two or rule two, this is how we label it."}, {"title": "Naming of Alkenes.txt", "text": "So we name our alkene simply one."}, {"title": "Naming of Alkenes.txt", "text": "Butane so the in part simply means our double bond is found on the first position and we have a four carbon backbone."}, {"title": "Naming of Alkenes.txt", "text": "So butte means we have a four carbon backbone."}, {"title": "Naming of Alkenes.txt", "text": "So let's go to example B."}, {"title": "Naming of Alkenes.txt", "text": "In example B, we have a symmetrical molecule, a symmetrical compound."}, {"title": "Naming of Alkenes.txt", "text": "And that simply means that it doesn't matter if we begin on this end or this end, we get the same alkyne, the same alkyne name."}, {"title": "Naming of Alkenes.txt", "text": "So let's begin counting our carbons."}, {"title": "Naming of Alkenes.txt", "text": "Carbon one, carbon two, carbon three, and carbon four."}, {"title": "Naming of Alkenes.txt", "text": "Now now we have two double bonds."}, {"title": "Naming of Alkenes.txt", "text": "So according to rule number three, we have to name this compound a dyene."}, {"title": "Naming of Alkenes.txt", "text": "So our name becomes one three."}, {"title": "Naming of Alkenes.txt", "text": "Butene so the dying part means we have two double bonds, one on the first carbon and the second one on the third carbon."}, {"title": "Naming of Alkenes.txt", "text": "Buta simply means we have a four carbon backbone."}, {"title": "Naming of Alkenes.txt", "text": "So let's go to example C.\nSo in example C, we have the following compound."}, {"title": "Naming of Alkenes.txt", "text": "So let's begin numbering."}, {"title": "Naming of Alkenes.txt", "text": "So remember, we want to find the longest possible carbon backbone that contains all the double bonds."}, {"title": "Naming of Alkenes.txt", "text": "So that means we either begin on this end and end on this end, or we begin on this end and go to this end."}, {"title": "Naming of Alkenes.txt", "text": "Since we want to find the lowest possible number values, we begin on this end."}, {"title": "Naming of Alkenes.txt", "text": "So 123456 and seven."}, {"title": "Naming of Alkenes.txt", "text": "So we have a seven carbon backbone."}, {"title": "Naming of Alkenes.txt", "text": "Our first double bond begins on the first carbon."}, {"title": "Naming of Alkenes.txt", "text": "The second double bond begins on the third carbon."}, {"title": "Naming of Alkenes.txt", "text": "And also on the third carbon, we have this Ethyl group."}, {"title": "Naming of Alkenes.txt", "text": "So this group comes first, so three Ethyl."}, {"title": "Naming of Alkenes.txt", "text": "And then we have one comma, three one comma, three Hecta, because we have a seven carbon backbone, dying because we have two double bonds."}, {"title": "Naming of Alkenes.txt", "text": "So once again, two double bonds, one on the first carbon, second one on the third carbon, we have an Ethyl group on the third carbon, and we have a seven carbon backbone hepta."}, {"title": "Naming of Alkenes.txt", "text": "So three Ethyl, one three Hepta, dying for this compound."}, {"title": "Naming of Alkenes.txt", "text": "So compound D.\nSo now we have a ring, a compound, a ring structure."}, {"title": "Naming of Alkenes.txt", "text": "So let's begin labeling on this guy, on this carbon."}, {"title": "Naming of Alkenes.txt", "text": "So 123456."}, {"title": "Naming of Alkenes.txt", "text": "So once again, I begin labeling or numbering on my double bond because I want my double bond to have the lowest possible number value."}, {"title": "Naming of Alkenes.txt", "text": "So this guy is known as one cyclone because it's a cyclic compound, and we have six, so hexene."}, {"title": "Naming of Alkenes.txt", "text": "So one cyclohexine, or simply cyclohexine."}, {"title": "Naming of Alkenes.txt", "text": "So let's go to part E, or compound E. So once again, I want to label my compound in a way such that my double bond gets the lowest possible number value, and this methyl group also gets the lowest possible number value."}, {"title": "Naming of Alkenes.txt", "text": "So I begin on this side."}, {"title": "Naming of Alkenes.txt", "text": "So one carbon, second carbon, third carbon, fourth carbon, fifth carbon, 6th carbon."}, {"title": "Naming of Alkenes.txt", "text": "So once again, I have a 6th carbon ring."}, {"title": "Naming of Alkenes.txt", "text": "And so I named this guy."}, {"title": "Naming of Alkenes.txt", "text": "So, notice that my methyl group is found on the third carbon."}, {"title": "Naming of Alkenes.txt", "text": "So I name it three methyl, one cycloxine."}, {"title": "Naming of Alkenes.txt", "text": "So three methyl simply means our methyl group is in the third carbon, and one cyclohexine means that my double bond is found on the first carbon, and we have a ring."}, {"title": "Naming of Alkenes.txt", "text": "So finally, we get to compound E. So in compound E, we have a cyclic six carbon backbone, and we have three double bonds."}, {"title": "Naming of Alkenes.txt", "text": "So let's begin labeling or numbering."}, {"title": "Naming of Alkenes.txt", "text": "And actually doesn't matter where we begin numbering or labeling because this is a symmetrical compound."}, {"title": "Naming of Alkenes.txt", "text": "So 123456."}, {"title": "Naming of Alkenes.txt", "text": "So we have one three five so one three and five cyclotex."}, {"title": "Naming of Alkenes.txt", "text": "One three five presents our double bonds."}, {"title": "Naming of Alkenes.txt", "text": "We have three double bonds, so we have a triangle, and we have a six member cyclic ring."}, {"title": "Naming of Alkenes.txt", "text": "So one three, five cyclohexa triumph."}, {"title": "Naming of Alkenes.txt", "text": "And this is also known as simply benzene."}, {"title": "Naming of Alkenes.txt", "text": "So benzene is the same thing as one three, five cyclohexa triangle."}, {"title": "Alkali and Alkaline Earth Metals .txt", "text": "Today we're going to compare and contrast two important groups or families found on our periodic table."}, {"title": "Alkali and Alkaline Earth Metals .txt", "text": "We're going to look at alkali metals and alkaline earth metals."}, {"title": "Alkali and Alkaline Earth Metals .txt", "text": "So let's begin with these guys."}, {"title": "Alkali and Alkaline Earth Metals .txt", "text": "So the alkaline metals are found on group one or group one A on our periodic table."}, {"title": "Alkali and Alkaline Earth Metals .txt", "text": "So that means these guys are metals or part of that a metal division."}, {"title": "Alkali and Alkaline Earth Metals .txt", "text": "So that applies that they are soft, malleable and ductile."}, {"title": "Alkali and Alkaline Earth Metals .txt", "text": "Duct till simply means they're stretchy or stretchable malleable simply means we can hammer them into thin sheets of metal and soft."}, {"title": "Alkali and Alkaline Earth Metals .txt", "text": "Well, it simply means they're soft."}, {"title": "Alkali and Alkaline Earth Metals .txt", "text": "These guys also display lust alike properties, which simply means they are shiny."}, {"title": "Alkali and Alkaline Earth Metals .txt", "text": "Now, metals are shiny, so that makes sense."}, {"title": "Alkali and Alkaline Earth Metals .txt", "text": "And these guys, because they're metals, they conduct electricity."}, {"title": "Alkali and Alkaline Earth Metals .txt", "text": "In other words, electrons are capable of moving from one point to another in alkali metals very easily."}, {"title": "Alkali and Alkaline Earth Metals .txt", "text": "And that means because moving charge creates electricity, these guys create or conduct electricity very well."}, {"title": "Alkali and Alkaline Earth Metals .txt", "text": "Now, they also form ions with a positive oxidation state."}, {"title": "Alkali and Alkaline Earth Metals .txt", "text": "In other words, they're capable of losing electrons very easily, and therefore, they usually form plus one oxidation states."}, {"title": "Alkali and Alkaline Earth Metals .txt", "text": "So a positive oxidation state."}, {"title": "Alkali and Alkaline Earth Metals .txt", "text": "Now, these guys are highly reactive when you mix them with nonmetals and they form ionic compounds."}, {"title": "Alkali and Alkaline Earth Metals .txt", "text": "For example, if we react these guys with an H, they will form something called metal Hydrides nah, lih, et cetera, in which the NA and the li both have a positive one oxidation state."}, {"title": "Alkali and Alkaline Earth Metals .txt", "text": "Now, if you mix the metals with water, they will react exothermically to produce a metal hydroxide and H two gas."}, {"title": "Alkali and Alkaline Earth Metals .txt", "text": "Let's put this guy's in parentheses gas."}, {"title": "Alkali and Alkaline Earth Metals .txt", "text": "So, for example, if you make two moles of sodium in a solid state with two moles of water, you will get two moles of metal hydroxide and 1 mol of H two or diatomic gas."}, {"title": "Alkali and Alkaline Earth Metals .txt", "text": "Now, let's look at the second type of group right next to our alkaline metals, known as alkaline earth metals."}, {"title": "Alkali and Alkaline Earth Metals .txt", "text": "Now, these guys are obviously in group two or group two A on our periodic table."}, {"title": "Alkali and Alkaline Earth Metals .txt", "text": "And these guys, just like the alkaline metals, are also part of the metal division."}, {"title": "Alkali and Alkaline Earth Metals .txt", "text": "So they're metals."}, {"title": "Alkali and Alkaline Earth Metals .txt", "text": "But unlike these guys, which are soft, these guys are harder and more dense."}, {"title": "Alkali and Alkaline Earth Metals .txt", "text": "That means their molecules in a solid state are closer together per unit volume."}, {"title": "Alkali and Alkaline Earth Metals .txt", "text": "Now, since they're metals, they're also malleable duct till and they conduct electricity well."}, {"title": "Alkali and Alkaline Earth Metals .txt", "text": "Now, these guys, unlike these guys, form plus two oxidation state."}, {"title": "Alkali and Alkaline Earth Metals .txt", "text": "In other words, these guys lose not one electron but two electrons when they react with our nonmetals."}, {"title": "Alkali and Alkaline Earth Metals .txt", "text": "So that means they're more likely to lose electrons."}, {"title": "Alkali and Alkaline Earth Metals .txt", "text": "Now, our alkaline earth metals are less reactive than the alkali metals, but still react with the nonmetals to form ionic compounds."}, {"title": "Alkali and Alkaline Earth Metals .txt", "text": "For example, calcium reacts with hydrogen to form calcium Hydride CAH two."}, {"title": "Alkali and Alkaline Earth Metals .txt", "text": "And calcium also reacts with hydroxide when we mix them with water to form our calcium hydroxide molecule, in which we have two hydroxides because each hydroxide has an oxidation state of negative one to balance out the plus two states on our alkaline earth metal, the calcium."}, {"title": "Alkali and Alkaline Earth Metals .txt", "text": "We need two of these guys."}, {"title": "Rate Law .txt", "text": "So we already spoke about the concept of rate law."}, {"title": "Rate Law .txt", "text": "And we said that rate law is a mathematical representation between the relationship of the concentration of reactants and our reaction rates."}, {"title": "Rate Law .txt", "text": "Now, we also said that rate law can only be determined using experimental results."}, {"title": "Rate Law .txt", "text": "And that's exactly right."}, {"title": "Rate Law .txt", "text": "Now, in this lecture, we're going to look at the following form reaction and try to determine our rate law using some experimental data."}, {"title": "Rate Law .txt", "text": "So let's begin."}, {"title": "Rate Law .txt", "text": "1 mol of methyl acetate react with 1 mol of hydroxide to produce 1 mol of acetate ion and 1 mol of methanol."}, {"title": "Rate Law .txt", "text": "Now, let's conduct the following three experiments in which we measure in each experiment the concentration of methylacetate and hydroxide and we find the initial rate."}, {"title": "Rate Law .txt", "text": "Now, our goal is to see how our initial rate changes when we change our concentration of reactants."}, {"title": "Rate Law .txt", "text": "Now, the first experiment will serve as a control."}, {"title": "Rate Law .txt", "text": "We're going to basically compare our second and third experiment to our first experiment and see how our initial rate changes."}, {"title": "Rate Law .txt", "text": "So in the first experiment, we see that we have 0.5\nmolar of initial methyl acetate and 0.5 molar of our initial hydroxide."}, {"title": "Rate Law .txt", "text": "Now, when these two concentrations are 0.5\neach, our initial rate is 0.2."}, {"title": "Rate Law .txt", "text": "Next, our goal is to change one of these guys and see how our initial rate is influenced."}, {"title": "Rate Law .txt", "text": "So let's keep our initial hydroxide concentration the same and only change our initial concentration of methyl acetate."}, {"title": "Rate Law .txt", "text": "So let's double it."}, {"title": "Rate Law .txt", "text": "So we double it to 0.1 molar, and this guy stays at 0.5\nmolar, and we see that our initial rate also doubles to 0.4."}, {"title": "Rate Law .txt", "text": "Now, that means that because we double this and our initial rate doubles, these guys are directly proportional."}, {"title": "Rate Law .txt", "text": "In other words, if you double this guy, you must double the initial rate."}, {"title": "Rate Law .txt", "text": "So let's conduct the same exact experiment."}, {"title": "Rate Law .txt", "text": "But now we keep our initial concentration of methyl acetate the same, and we double our concentration of our initial hydroxide."}, {"title": "Rate Law .txt", "text": "So let's stay at 0.1\nmolar and go from 0.5 molar of our hydroxide to 0.1 molar."}, {"title": "Rate Law .txt", "text": "We see that when we double our initial concentration of hydroxide, our initial rate also doubles."}, {"title": "Rate Law .txt", "text": "That means that our hydroxide is also proportional to our rate."}, {"title": "Rate Law .txt", "text": "So now with this result, we can find our rate law."}, {"title": "Rate Law .txt", "text": "So, rate law is the following equation the rate of my reaction in the forward direction is equal to the rate constant of the forward reaction times the concentration of methylacetate times the concentration of hydroxide."}, {"title": "Rate Law .txt", "text": "Now, notice my exponents are each one."}, {"title": "Rate Law .txt", "text": "That means there is a direct relationship between our rate of reaction and our concentration."}, {"title": "Rate Law .txt", "text": "In other words, if we double our concentration of methyl acetate while keeping this guy the same, we double our rate of reaction."}, {"title": "Rate Law .txt", "text": "Likewise, if we double this guy while keeping our methyl acetate the same, we also double our reaction rate."}, {"title": "Rate Law .txt", "text": "But if we double each guy, if this guy is multiplied by two and this guy is multiplied by two, that means this guy is quadrupled."}, {"title": "Rate Law .txt", "text": "He's multiplied by four."}, {"title": "Rate Law .txt", "text": "So now I have this."}, {"title": "Rate Law .txt", "text": "I have this and I know my rate of reaction, but I don't know my rate constant."}, {"title": "Rate Law .txt", "text": "Now, the rate constant can also be found using our experimental results."}, {"title": "Rate Law .txt", "text": "The way we do it is we choose any experiment we like and we plug in the data points and we find our KF."}, {"title": "Rate Law .txt", "text": "So let's use the first experiment."}, {"title": "Rate Law .txt", "text": "Let's plug in 0.5 for this guy, 0.5 for this guy, and 0.2\nfor our rate of reaction, the forward direction."}, {"title": "Rate Law .txt", "text": "So we plug these guys in and we solve for KF and we get 0.002 divided by zero."}, {"title": "Rate Law .txt", "text": "Five 0.5 times 0.05 gives us 0.08."}, {"title": "Rate Law .txt", "text": "So that means our KF, our rate constant for this reaction going this way is 0.8."}, {"title": "Rate Law .txt", "text": "So now we plug this into our reaction and we find the final rate law to be the rate of our four reaction is equal to 0.8 times the concentration of our methyl acetate to the first power."}, {"title": "Rate Law .txt", "text": "Times the concentration of our hydroxide to the first power."}, {"title": "Rate Law .txt", "text": "Now, let's think about it."}, {"title": "Rate Law .txt", "text": "So our initial concentration increases and that increase increases our initial rates."}, {"title": "Rate Law .txt", "text": "Why is that?"}, {"title": "Rate Law .txt", "text": "Well, think about it."}, {"title": "Rate Law .txt", "text": "The only way that these guys react is if they collide."}, {"title": "Rate Law .txt", "text": "And if you increase the concentration of either guy, we have more collisions happening."}, {"title": "Rate Law .txt", "text": "And if there are more collisions happening, that means our rate should increase."}, {"title": "Rate Law .txt", "text": "In other words, these guys will convert quicker to our products from the reactants."}, {"title": "Rate Law .txt", "text": "Now, likewise, if you decrease either concentration, our rate should decrease because we have less collisions occurring."}, {"title": "Rate Law .txt", "text": "So our rate constant will be less and therefore our rate will be less."}, {"title": "Molarity Example .txt", "text": "One of the different ways that people could measure the concentration of a solution is using molarity."}, {"title": "Molarity Example .txt", "text": "What is molarity?"}, {"title": "Molarity Example .txt", "text": "Molarity is represented by the capital letter M, and it has the unit moles of solid over volume of solution."}, {"title": "Molarity Example .txt", "text": "And this includes the volume of both the solvent and the solid."}, {"title": "Molarity Example .txt", "text": "Now let's do an example using molar."}, {"title": "Molarity Example .txt", "text": "The question tells us that we have 0.6 liters of a three molar solution."}, {"title": "Molarity Example .txt", "text": "We need to find the number of liters that we need to add to go from three molar to a one molar solution."}, {"title": "Molarity Example .txt", "text": "So we're diluting."}, {"title": "Molarity Example .txt", "text": "Whenever we dilute, we want to keep the number of solid the same."}, {"title": "Molarity Example .txt", "text": "We want to increase the number of solids."}, {"title": "Molarity Example .txt", "text": "So this is our current situation."}, {"title": "Molarity Example .txt", "text": "We have a three molar solution where the red dots are the solid, blue dots are the solid."}, {"title": "Molarity Example .txt", "text": "We want to go from a three molar to a one molar solution."}, {"title": "Molarity Example .txt", "text": "So we need to ask ourselves, how many more blue dots do we need to add to go from a three molar to a one molar?"}, {"title": "Molarity Example .txt", "text": "So since the number of red dots stays the same, we need to find the constant."}, {"title": "Molarity Example .txt", "text": "The constant here is the number of moles of solute."}, {"title": "Molarity Example .txt", "text": "To find the number of moles of solute, we take 0.6 liters and we multiply it by three molar."}, {"title": "Molarity Example .txt", "text": "0.6\nliters times three moles of solute over liters."}, {"title": "Molarity Example .txt", "text": "The L's cross out 0.6 times three."}, {"title": "Molarity Example .txt", "text": "We get 1.8 moles of solution."}, {"title": "Molarity Example .txt", "text": "Now, we found the number of red dots or the moles of red dots."}, {"title": "Molarity Example .txt", "text": "Now, our goal is a one molar solution."}, {"title": "Molarity Example .txt", "text": "So we set up an equation."}, {"title": "Molarity Example .txt", "text": "One molar is equal to the thing that stays constant, one moles of solution."}, {"title": "Molarity Example .txt", "text": "Over what the amount?"}, {"title": "Molarity Example .txt", "text": "We already have 0.6 liters plus the amount we need to add the mount of blue dots that we need to add to the system to get one molar solution."}, {"title": "Molarity Example .txt", "text": "Okay, now we do a little bit of algebra, and we get x equals 1.2\nliters of solvent."}, {"title": "Molarity Example .txt", "text": "In other words, we need to add 1.2 liters worth of blue dots to get a one molar solution."}, {"title": "Sp2 Hybridization.txt", "text": "So in the previous lecture, we began our discussion on hybridization and we develop sphybidized orbitals."}, {"title": "Sp2 Hybridization.txt", "text": "So we essentially took one S orbital, we took one P orbital, we combine them, and we formed two different sphypedized orbitals."}, {"title": "Sp2 Hybridization.txt", "text": "Now we're going to look at SP two hybridized orbitals."}, {"title": "Sp2 Hybridization.txt", "text": "So let's suppose we want to construct a BH three molecule."}, {"title": "Sp2 Hybridization.txt", "text": "Now, in order to construct this molecule, we need three H atoms and one boron atom."}, {"title": "Sp2 Hybridization.txt", "text": "Now, boron has five protons, so has five electrons."}, {"title": "Sp2 Hybridization.txt", "text": "Two go into the one S, two go into the two S, and one goes into the two piece."}, {"title": "Sp2 Hybridization.txt", "text": "So we have three balanced electrons."}, {"title": "Sp2 Hybridization.txt", "text": "Now, the H atom each has one electron."}, {"title": "Sp2 Hybridization.txt", "text": "So the one electron goes into the one S orbital."}, {"title": "Sp2 Hybridization.txt", "text": "Now, before these atoms can combine to form, our BH three molecule hybridization of boron must take place."}, {"title": "Sp2 Hybridization.txt", "text": "The question is, how many hybrid orbitals should boron form before this molecule can be created?"}, {"title": "Sp2 Hybridization.txt", "text": "The answer lies in this molecule itself."}, {"title": "Sp2 Hybridization.txt", "text": "How many times does boron bond two H?"}, {"title": "Sp2 Hybridization.txt", "text": "Well, since there's one boron and three H atoms, that means there are three different orbitals."}, {"title": "Sp2 Hybridization.txt", "text": "So that means we must develop three hybrid orbitals."}, {"title": "Sp2 Hybridization.txt", "text": "So that means we can no longer use SP hybridization, because SP hybridization produces only two hybrid orbitals."}, {"title": "Sp2 Hybridization.txt", "text": "And we need three, as we see in this case here."}, {"title": "Sp2 Hybridization.txt", "text": "So that means we're not combining S and P, but we're combining three orbitals."}, {"title": "Sp2 Hybridization.txt", "text": "And these three orbitals are the two S orbital, the two PX orbital, and the two PY orbital."}, {"title": "Sp2 Hybridization.txt", "text": "So we combine these atomic orbitals of the boron atom, and we form three identical SP, two orbitals or hybrid orbitals."}, {"title": "Sp2 Hybridization.txt", "text": "And these guys look like this hybrid orbital here."}, {"title": "Sp2 Hybridization.txt", "text": "The only difference is they all lie in different directions."}, {"title": "Sp2 Hybridization.txt", "text": "So they point in different directions."}, {"title": "Sp2 Hybridization.txt", "text": "So that means because we're combining two P orbitals and one two S orbital, we're going to have 66% P character and 33% S character."}, {"title": "Sp2 Hybridization.txt", "text": "So now that we formed the three different hybrid orbitals, we are ready for these orbitals to interact with the one S orbitals of the H.\nSo we take three one S orbitals, we combine them with three SP two orbitals, and we form the following picture."}, {"title": "Sp2 Hybridization.txt", "text": "So here we have our boron atom."}, {"title": "Sp2 Hybridization.txt", "text": "The nucleus is in the middle here."}, {"title": "Sp2 Hybridization.txt", "text": "It's not shown."}, {"title": "Sp2 Hybridization.txt", "text": "We have one SP hybridized orbital pointing into the page into the board, and it's bonding to one of the S's."}, {"title": "Sp2 Hybridization.txt", "text": "One is coming out of the board, and that is bonding to a second one S orbital."}, {"title": "Sp2 Hybridization.txt", "text": "And a third is lying on the board, and it's bonding with a third one S orbital."}, {"title": "Sp2 Hybridization.txt", "text": "And here we have our BH three molecule that also looks like this."}, {"title": "Sp2 Hybridization.txt", "text": "So once again, the boron nucleus, one bond is coming out of the page."}, {"title": "Sp2 Hybridization.txt", "text": "The second bond is going into the page, and the third is going this way."}, {"title": "Sp2 Hybridization.txt", "text": "Now, if we grab the XYZ axis, we see that this molecule lies on the same plane."}, {"title": "Sp2 Hybridization.txt", "text": "All the bonds lie on the same plane."}, {"title": "Sp2 Hybridization.txt", "text": "So that means since we have three angles, each angle must be 120 degrees."}, {"title": "Sp2 Hybridization.txt", "text": "So, once again, let's review."}, {"title": "Sp2 Hybridization.txt", "text": "So what is an SP two hybridized orbital?"}, {"title": "Sp2 Hybridization.txt", "text": "Well, an SP two hybridized orbital is simply the combination of three different atomic orbitals found within an atom."}, {"title": "Sp2 Hybridization.txt", "text": "In this case, it was the Boron atom."}, {"title": "Sp2 Hybridization.txt", "text": "When these three different atomic orbitals combined, they form identical hybrid orbitals."}, {"title": "Sp2 Hybridization.txt", "text": "Remember, the amount of orbitals that go into the combination must equal to the amount of hybrid orbitals we form."}, {"title": "Sp2 Hybridization.txt", "text": "So if we include three if we input three we you must produce three orbitals."}, {"title": "Polyprotic Acids .txt", "text": "Now, as of now, we've only really spoken about monoprotic acids."}, {"title": "Polyprotic Acids .txt", "text": "Now, monoprotic acid is an acid that can donate a single H plus ion."}, {"title": "Polyprotic Acids .txt", "text": "Let's look at a few examples."}, {"title": "Polyprotic Acids .txt", "text": "Hydrochloric acid, acetic acid, nitric acid, hydrobromic acid, hydrochloric acid, chloro acid, and perchloric acid are all examples of monopolic acids because they can all donate a single H plus ion."}, {"title": "Polyprotic Acids .txt", "text": "Now let's look at the ionization of these acids in water."}, {"title": "Polyprotic Acids .txt", "text": "Let's choose the hypothetical monopolic acid."}, {"title": "Polyprotic Acids .txt", "text": "So let's choose Ha to be our acid."}, {"title": "Polyprotic Acids .txt", "text": "And Ha will react in water to produce hydronium and a conjugate base."}, {"title": "Polyprotic Acids .txt", "text": "Now, we've spoken about something called Ka, or the acid ionization concept."}, {"title": "Polyprotic Acids .txt", "text": "If you don't know what K is, check out the link above."}, {"title": "Polyprotic Acids .txt", "text": "But Ka is basically the product of the concentrations of the product."}, {"title": "Polyprotic Acids .txt", "text": "So the concentration of this guy times the concentration of this guy divided by the concentration of the reaction of this guy."}, {"title": "Polyprotic Acids .txt", "text": "And we said that if our Ka value is high, if it's bigger than one, that means our acid is a strong acid."}, {"title": "Polyprotic Acids .txt", "text": "And if our Ka is low, if it's less than one, we're dealing with a weak acid."}, {"title": "Polyprotic Acids .txt", "text": "Now, by strong acid, I simply need an acid that's willing to dissociate, that's willing to go from this form to this form."}, {"title": "Polyprotic Acids .txt", "text": "So therefore, if our Ka is high, that means the concentration of these guys is high and the concentration of this guy is low."}, {"title": "Polyprotic Acids .txt", "text": "And that makes sense."}, {"title": "Polyprotic Acids .txt", "text": "Now let's look at polyphonic acid."}, {"title": "Polyprotic Acids .txt", "text": "Polyportic acids are those acids that can donate more than one H plus ion."}, {"title": "Polyprotic Acids .txt", "text": "So let's look at a few examples."}, {"title": "Polyprotic Acids .txt", "text": "Sulfuric acid, hydronium ion, phosphoric acid and carbonic acid are all examples of polyphonic acids."}, {"title": "Polyprotic Acids .txt", "text": "And that's because they all have more than two or more than one H plus ion that they can donate."}, {"title": "Polyprotic Acids .txt", "text": "This guy has three H plus ions that he can donate."}, {"title": "Polyprotic Acids .txt", "text": "So in the same way that we spoke about ionization reactions of monopolytic acids, we can also talk about ionization reactions of polyphotic acids."}, {"title": "Polyprotic Acids .txt", "text": "So let's look at a hypothetical example of a polyphotic acid, h two A."}, {"title": "Polyprotic Acids .txt", "text": "Now, for H two A, we're not going to have one reaction."}, {"title": "Polyprotic Acids .txt", "text": "We're going to have two reactions."}, {"title": "Polyprotic Acids .txt", "text": "And that's because we have two potential HS that can be lost to our environment."}, {"title": "Polyprotic Acids .txt", "text": "So H two A will react in water to produce hydronium and our conjugate base."}, {"title": "Polyprotic Acids .txt", "text": "Now let's look at this conjugate base."}, {"title": "Polyprotic Acids .txt", "text": "This conjugate base can either go two ways."}, {"title": "Polyprotic Acids .txt", "text": "It can either act as a conjugate base, taking this H back and creating back our acid, or it can act as an acid itself and it can react with water to produce a second hydronium ion and the final conjugate base."}, {"title": "Polyprotic Acids .txt", "text": "Now, the same way we spoke about Ka or acidization constants for monoprotic acids, we can also talk about Ka's about polyproteic acids."}, {"title": "Polyprotic Acids .txt", "text": "Except now we're not going to have one Ka."}, {"title": "Polyprotic Acids .txt", "text": "We're going to have more than one Ka."}, {"title": "Polyprotic Acids .txt", "text": "Each Ka represents a single reaction."}, {"title": "Polyprotic Acids .txt", "text": "So, for this particular polyphonic acids, we have two reactions."}, {"title": "Polyprotic Acids .txt", "text": "So we have two ka's."}, {"title": "Polyprotic Acids .txt", "text": "And normally, the first ka will have a higher value than the second ka."}, {"title": "Polyprotic Acids .txt", "text": "And that's because of the following fact."}, {"title": "Polyprotic Acids .txt", "text": "Now, when we go from this acid to this base, we get a negative one charge."}, {"title": "Polyprotic Acids .txt", "text": "When we go from this acid to this base, we get a negative two charge."}, {"title": "Polyprotic Acids .txt", "text": "Which one of these is less stable?"}, {"title": "Polyprotic Acids .txt", "text": "Well, this guy."}, {"title": "Polyprotic Acids .txt", "text": "And that's because the more charge we have, the less stability."}, {"title": "Polyprotic Acids .txt", "text": "And so this guy will not want to exist by itself."}, {"title": "Polyprotic Acids .txt", "text": "This guy will want to exist in this form."}, {"title": "Polyprotic Acids .txt", "text": "And so our reaction for this guy is favored this way."}, {"title": "Polyprotic Acids .txt", "text": "And that's why our ka is much smaller for this reaction than this reaction."}, {"title": "Polyprotic Acids .txt", "text": "And in fact, this reaction is 10,000 times more likely than this reaction."}, {"title": "Polyprotic Acids .txt", "text": "So, in the same way that we spoke about titration curves of monopolic acids, we can also talk about titration curves of polyphonic acids."}, {"title": "Polyprotic Acids .txt", "text": "So here's our titration curve."}, {"title": "Polyprotic Acids .txt", "text": "While the Y axis is PH and the X axis is volume based at it."}, {"title": "Polyprotic Acids .txt", "text": "Now, this curve is for our hypothetical phypotic acid, h two A."}, {"title": "Polyprotic Acids .txt", "text": "Now, this guy will have not one equivalence point, but two equivalence points."}, {"title": "Polyprotic Acids .txt", "text": "And let's look at what each represents."}, {"title": "Polyprotic Acids .txt", "text": "Let's look at the first one."}, {"title": "Polyprotic Acids .txt", "text": "What the first one represents is it's the point at which all of this guy has been neutralized to this guy."}, {"title": "Polyprotic Acids .txt", "text": "So there's no more of this guy, and 100% of our solution is in this form at this point."}, {"title": "Polyprotic Acids .txt", "text": "Now, what the second point means is it's the point at which all of this guy has been neutralized into our final conjugate base."}, {"title": "Polyprotic Acids .txt", "text": "And at this point, as a second equivalence point, all of our solution is in this form."}, {"title": "Polyprotic Acids .txt", "text": "So, at this point, we notice we have a very high PH."}, {"title": "Polyprotic Acids .txt", "text": "And a high PH means we're in a basic environment."}, {"title": "Polyprotic Acids .txt", "text": "And basic means we don't have a lot of H plus ions."}, {"title": "Polyprotic Acids .txt", "text": "So why is it that at this point, this guy really wants to associate into this guy?"}, {"title": "Polyprotic Acids .txt", "text": "Well, let's examine why."}, {"title": "Polyprotic Acids .txt", "text": "Well, in our high PH or a basic environment, we don't have a lot of H plus, so this guy decreases."}, {"title": "Polyprotic Acids .txt", "text": "So to compensate that, according to Alicia clear principle, this guy will dissociate."}, {"title": "Polyprotic Acids .txt", "text": "So our equilibrium will be favored this way."}, {"title": "Polyprotic Acids .txt", "text": "And that's exactly why at a high PH, our reaction goes this way."}, {"title": "Polyprotic Acids .txt", "text": "And at a low PH, our reaction goes this way, because at a low PH, we have a lot of H plus ions, so our equilibrium will be favored this way."}, {"title": "Reaction Rates and Rate Law .txt", "text": "Talk about rate of reactions and see exactly how the two are related."}, {"title": "Reaction Rates and Rate Law .txt", "text": "So, let's look at the following elementary equation."}, {"title": "Reaction Rates and Rate Law .txt", "text": "Now, we begin with two reactants, x and Y and they convert into W and Z."}, {"title": "Reaction Rates and Rate Law .txt", "text": "What elementary simply means is that they convert from reactants to products in a single step."}, {"title": "Reaction Rates and Rate Law .txt", "text": "Elementary reactions are some of the most basic reactions out there."}, {"title": "Reaction Rates and Rate Law .txt", "text": "Now notice that A-B-C and D are coefficients of each respective molecule and they represent the number of molecules or moles."}, {"title": "Reaction Rates and Rate Law .txt", "text": "Now, rates of reactions tell you how quickly reactants become products, so how quickly x and y become W and Z."}, {"title": "Reaction Rates and Rate Law .txt", "text": "In other words, the rate can be found by the change in concentration of reactants over some given time."}, {"title": "Reaction Rates and Rate Law .txt", "text": "Now, notice that we go from a positive amount or some amount to a small amount."}, {"title": "Reaction Rates and Rate Law .txt", "text": "So over time, our x and y will disappear."}, {"title": "Reaction Rates and Rate Law .txt", "text": "So therefore, the rate of these guys are negative because remember, we're subtracting our initial from final."}, {"title": "Reaction Rates and Rate Law .txt", "text": "An initial concentration of x is larger than final concentration of x."}, {"title": "Reaction Rates and Rate Law .txt", "text": "The final will be less."}, {"title": "Reaction Rates and Rate Law .txt", "text": "We'll have less x and y at the end because some of these guys will convert to W and Z."}, {"title": "Reaction Rates and Rate Law .txt", "text": "So once again, the rate or average rate of x is negative change in concentration of x over time."}, {"title": "Reaction Rates and Rate Law .txt", "text": "Now, time is also multiplied by A."}, {"title": "Reaction Rates and Rate Law .txt", "text": "Now, for the case that A-B-C and D are one, we simply take away the A, because one times T is T. So the same thing can be said for w for Y."}, {"title": "Reaction Rates and Rate Law .txt", "text": "The negative change in concentration of y over BT gives you the rate of disappearance of Y."}, {"title": "Reaction Rates and Rate Law .txt", "text": "Now, the rate of appearance of W and Z can be given by these formulas where now we have the positive because these guys appear and so these guys will both be positives."}, {"title": "Reaction Rates and Rate Law .txt", "text": "Now, let's look at the factors affecting our reaction rates."}, {"title": "Reaction Rates and Rate Law .txt", "text": "So, we already said that temperature affects our rates of reaction because it affects our rate constant."}, {"title": "Reaction Rates and Rate Law .txt", "text": "Now, if the rate constant increases, then our rate of reaction increases."}, {"title": "Reaction Rates and Rate Law .txt", "text": "And we'll see why at the end of this lecture."}, {"title": "Reaction Rates and Rate Law .txt", "text": "But notice that temperature increasing."}, {"title": "Reaction Rates and Rate Law .txt", "text": "Temperature affects rate constant by affecting the kinetic energy of molecules."}, {"title": "Reaction Rates and Rate Law .txt", "text": "On average, molecules will have higher kinetic energy and a higher temperature."}, {"title": "Reaction Rates and Rate Law .txt", "text": "And that means they will be more likely to overcome the activation energy barrier and become our products."}, {"title": "Reaction Rates and Rate Law .txt", "text": "Now, concentrations we see using these formulas affect or increase our rates."}, {"title": "Reaction Rates and Rate Law .txt", "text": "In other words, if we have higher concentration, if this guy becomes higher, this guy becomes higher, if this guy becomes higher and this guy becomes higher, our rates will increase."}, {"title": "Reaction Rates and Rate Law .txt", "text": "Now, pressure also has an effect on rates and we'll see how in another video."}, {"title": "Reaction Rates and Rate Law .txt", "text": "Now we spoke about elementary reactions in which reactants become products in a single step."}, {"title": "Reaction Rates and Rate Law .txt", "text": "Now, there are also multi step reactions and those include many different steps, intermediate steps."}, {"title": "Reaction Rates and Rate Law .txt", "text": "However, we can use this guide or this formula to approximate our rates of multistep reactions as long as the concentrations of intermediates are held relatively low."}, {"title": "Reaction Rates and Rate Law .txt", "text": "Now that means suppose we have the following reaction a plus B react to form intermediate AB and then that intermediate AB reacts with C, some other guy to form ABC."}, {"title": "Reaction Rates and Rate Law .txt", "text": "Now this guy is out intermediate."}, {"title": "Reaction Rates and Rate Law .txt", "text": "Now, as long as the concentration of this guy is kept relatively low, we can approximate using these formulas here."}, {"title": "Reaction Rates and Rate Law .txt", "text": "So likewise, the rate of change or disappearance of A and B can be given by negative change in concentration of B divided by T. Now that only works if that intermediate concentration is kept low."}, {"title": "Reaction Rates and Rate Law .txt", "text": "Now let's talk about the rate law."}, {"title": "Reaction Rates and Rate Law .txt", "text": "The rate law is a mathematical representation that summarizes relationship between reactants and reaction rate."}, {"title": "Reaction Rates and Rate Law .txt", "text": "And it also builds a relationship between our rate constant and our rate of reaction."}, {"title": "Reaction Rates and Rate Law .txt", "text": "Now notice in this reaction we have a forward reaction and a reverse reaction."}, {"title": "Reaction Rates and Rate Law .txt", "text": "Now, we're only going to worry about the forward reaction, but know that if there is a forward reaction, there could also be a reverse reaction."}, {"title": "Reaction Rates and Rate Law .txt", "text": "Now let's look at the rate law."}, {"title": "Reaction Rates and Rate Law .txt", "text": "The rate law is this entire equation or relation."}, {"title": "Reaction Rates and Rate Law .txt", "text": "So rate of the forward reaction of this reaction is given by our rate constant KF for the forward reaction times the concentration of X to the A power."}, {"title": "Reaction Rates and Rate Law .txt", "text": "In this case this A times the concentration of Y to the B power B."}, {"title": "Reaction Rates and Rate Law .txt", "text": "Now, the reason we chose A and B is because this is an elementary reaction."}, {"title": "Reaction Rates and Rate Law .txt", "text": "Now, if this was not an elementary reaction, we would not be able to use this A and B the way we did here."}, {"title": "Reaction Rates and Rate Law .txt", "text": "Now for now, we're only going to worry about elementary reactions."}, {"title": "Reaction Rates and Rate Law .txt", "text": "So this is our rate law."}, {"title": "Reaction Rates and Rate Law .txt", "text": "Now this KF, our rate constant depends strictly on temperature and types of reactants."}, {"title": "Reaction Rates and Rate Law .txt", "text": "It does not depend on the concentrations of reactants nor products."}, {"title": "Reaction Rates and Rate Law .txt", "text": "Now, we saw from another video that KF is known as the Iranians equation and it depends strictly on temperature."}, {"title": "Reaction Rates and Rate Law .txt", "text": "So at the same temperature we're going to use the same reactant for some given reaction."}, {"title": "Reaction Rates and Rate Law .txt", "text": "Now, if we change our reactants, we're also going to have to change our KF because our rate constant also depends on the types of reactants used."}, {"title": "Reaction Rates and Rate Law .txt", "text": "Now, one last thing I want to mention is that this rate law, this equation is determined strictly using experimental results."}, {"title": "Reaction Rates and Rate Law .txt", "text": "That's the only way we can determine this relation."}, {"title": "Reaction Rates and Rate Law .txt", "text": "We can't determine this relation using the formula above."}, {"title": "Reaction Rates and Rate Law .txt", "text": "We have to determine determine this formula using experiments and my next lecture, we're going to see exactly how we determine our rate law from initial experimental results."}]
\ No newline at end of file