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Aufbau Principle and Electron Configuration .txt | Then this is the proper electron configuration. So ions also can be represented using electron configuration. For example, let's look at sodium plus has eleven protons and ten elections. So in order to write the electric configuration for this guy, we simply take away one electron from the highest energy level. So in this case, it would be one S, two two S, two two P, six. And we took out one electron from the three S, one orbital, so that that guy disappeared. |
Aufbau Principle and Electron Configuration .txt | So in order to write the electric configuration for this guy, we simply take away one electron from the highest energy level. So in this case, it would be one S, two two S, two two P, six. And we took out one electron from the three S, one orbital, so that that guy disappeared. Now, if we make this guy into an ion, right? Let's say we make it into BR plus ion, we take one electron away. That means we take it away from the highest energy level. |
Real Gases and van der waals equation .txt | So far we have only spoken about the way ideal gas molecules behave. We still haven't spoken about how actual or real gas molecules behave. Now, recall that any ideal gas molecule will behave accordingly with the kinetic molecular theory which makes a few important assumptions. 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. 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. 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. |
Real Gases and van der waals equation .txt | 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. 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. 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. And we can't use this law to solve any form of problem. Now, let's see why this happens and let's see what breaks down. 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. |
Real Gases and van der waals equation .txt | And we can't use this law to solve any form of problem. Now, let's see why this happens and let's see what breaks down. 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. Now, suppose we go from this system to a much smaller system. So we decrease volume and we increase pressure but our temperature remains constant. 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. |
Real Gases and van der waals equation .txt | Now, suppose we go from this system to a much smaller system. So we decrease volume and we increase pressure but our temperature remains constant. 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. So that means we can use the kinetic theory to approximate how this behaves. Because if the distance is far then we can assume the volume of the molecules to be very, very small. And since they're far away, we can assume they don't attract or repel each other. |
Real Gases and van der waals equation .txt | So that means we can use the kinetic theory to approximate how this behaves. Because if the distance is far then we can assume the volume of the molecules to be very, very small. And since they're far away, we can assume they don't attract or repel each other. However, when we get to this state what happens here at high temperatures? Suppose this is 1000 ATM and still zero Celsius. So our volume has decreased tremendously and our pressure has increased but temperature remains the same. |
Real Gases and van der waals equation .txt | However, when we get to this state what happens here at high temperatures? Suppose this is 1000 ATM and still zero Celsius. So our volume has decreased tremendously and our pressure has increased but temperature remains the same. So at very high pressures the distance between any two molecules is approximately the same as the size of the molecule itself. Now, and I claim under this condition the kinetic theory breaks down. So let's see, what about the kinetic theory that breaks down in this system? |
Real Gases and van der waals equation .txt | So at very high pressures the distance between any two molecules is approximately the same as the size of the molecule itself. Now, and I claim under this condition the kinetic theory breaks down. So let's see, what about the kinetic theory that breaks down in this system? Well, now, the molecules are very close to each other. They're so close, in fact, that they will attract each other and repel each other. So the forces that we spoke about before that we neglected. |
Real Gases and van der waals equation .txt | Well, now, the molecules are very close to each other. They're so close, in fact, that they will attract each other and repel each other. So the forces that we spoke about before that we neglected. Now we have to take them into consideration. And these forces follow. Coulomb's law means that if our distance decreases, our force increases. |
Real Gases and van der waals equation .txt | Now we have to take them into consideration. And these forces follow. Coulomb's law means that if our distance decreases, our force increases. So if this one's positive and this one's negative they will attract each other according to Coulomb's law. So now one of the assumptions of the kinetic theory breaks down namely, the electrostatic forces. Electrostatic forces cannot be neglected when pressures are very high. |
Real Gases and van der waals equation .txt | So if this one's positive and this one's negative they will attract each other according to Coulomb's law. So now one of the assumptions of the kinetic theory breaks down namely, the electrostatic forces. Electrostatic forces cannot be neglected when pressures are very high. Now, let's look at the volume. Let's take this picture and zoom in. This is what we get. |
Real Gases and van der waals equation .txt | Now, let's look at the volume. Let's take this picture and zoom in. This is what we get. Notice that the space in between the molecules is approximately the same or has the same volume as the molecules themselves. Now, the volume can no longer be neglected. 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. |
Real Gases and van der waals equation .txt | Notice that the space in between the molecules is approximately the same or has the same volume as the molecules themselves. Now, the volume can no longer be neglected. 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. And that means the second assumption in our kinetic theory also breaks down. Namely, volume is no longer zero. So we see that in extreme conditions of high pressure our ideal gas law no longer holds. |
Real Gases and van der waals equation .txt | And that means the second assumption in our kinetic theory also breaks down. Namely, volume is no longer zero. So we see that in extreme conditions of high pressure our ideal gas law no longer holds. Now let's see why. Under low temperatures the ideal gas law also breaks down. 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. |
Real Gases and van der waals equation .txt | Now let's see why. Under low temperatures the ideal gas law also breaks down. 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. And therefore, they will all drop to the bottom of the container and they will collect and get very close. And if they're close, that means they're feeling electrostatic forces. And so our kinetic theory also breaks down on the low temperatures. |
Real Gases and van der waals equation .txt | And therefore, they will all drop to the bottom of the container and they will collect and get very close. And if they're close, that means they're feeling electrostatic forces. And so our kinetic theory also breaks down on the low temperatures. Now let's compare the pressure of ideal and real systems. 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. For real situations, for real gases, the pressure is less. |
Real Gases and van der waals equation .txt | Now let's compare the pressure of ideal and real systems. 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. For real situations, for real gases, the pressure is less. Well, why is it less? Well, when the molecule in the real gas travels it's attracted by other molecules. 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. |
Real Gases and van der waals equation .txt | Well, why is it less? Well, when the molecule in the real gas travels it's attracted by other molecules. 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. That means for ideal pressures, ideal pressures are higher than real pressures. Likewise, let's examine the conditions for volume of ideal versus volume of real. 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. |
Real Gases and van der waals equation .txt | That means for ideal pressures, ideal pressures are higher than real pressures. Likewise, let's examine the conditions for volume of ideal versus volume of real. 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. And that means the volume will be plus the volume of the molecules. And so the volume of real gases will be greater. So now let's see what the gas law is for real gases. |
Real Gases and van der waals equation .txt | And that means the volume will be plus the volume of the molecules. And so the volume of real gases will be greater. So now let's see what the gas law is for real gases. So recall that the ideal gas law states that pressure of the ideal system times volume of ideal system gives you NRT. And now notice that in a real system and an ideal system this NRT remains the same. This remains a constant. |
Real Gases and van der waals equation .txt | So recall that the ideal gas law states that pressure of the ideal system times volume of ideal system gives you NRT. And now notice that in a real system and an ideal system this NRT remains the same. This remains a constant. Because if we're talking about the same temperature our T in both ideal and non ideal conditions stays the same. Our R remains a constant and our number of moles does not change. So in both ideal and non ideal systems this guy remains constant. |
Real Gases and van der waals equation .txt | Because if we're talking about the same temperature our T in both ideal and non ideal conditions stays the same. Our R remains a constant and our number of moles does not change. So in both ideal and non ideal systems this guy remains constant. The only thing that changes is pressure and volume. And so suppose we have P ideal and V ideal. Now, from this information we know that our P real is smaller than our P ideal. |
Real Gases and van der waals equation .txt | The only thing that changes is pressure and volume. And so suppose we have P ideal and V ideal. Now, from this information we know that our P real is smaller than our P ideal. 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. And so, from experiments, scientists found out what this X and what this Y was. This X is N squared times A over V. Two this Y is N times B. |
Real Gases and van der waals equation .txt | 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. And so, from experiments, scientists found out what this X and what this Y was. This X is N squared times A over V. Two this Y is N times B. Now, an is simply number of moles, and B is volume a and B are constants that depend on the gas being used. And so they're different for different gases. 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. |
Conjugate Acid-Base Pairs .txt | In this lecture we're going to talk about the concept of conjugate acidbased pairs. So whenever we have an acid that donates an H plus ion to a base, a new base and a new acid are formed. So, for example, let's look at the reaction of acetic acid and water. So in this case, our bronze and Lyley acid is our acetic acid and our bronchylori base is our water. And that's because this guy has an extra H ion. It donates that H plus ion. |
Conjugate Acid-Base Pairs .txt | So in this case, our bronze and Lyley acid is our acetic acid and our bronchylori base is our water. And that's because this guy has an extra H ion. It donates that H plus ion. And this guy has a lone pair of electrons on its oxygen. And it has the potential to gain a proton. So this is our brocholyari base. |
Conjugate Acid-Base Pairs .txt | And this guy has a lone pair of electrons on its oxygen. And it has the potential to gain a proton. So this is our brocholyari base. Now, when they react this guy, our CBIC acid loses NH ion, while this guy, our water, gains NH ion. And that means if we look at these guys, this becomes our new base, our new bronze of Larry base. Because it now has the potential to gain an H ion because it has that electron pair on the O atom. |
Conjugate Acid-Base Pairs .txt | Now, when they react this guy, our CBIC acid loses NH ion, while this guy, our water, gains NH ion. And that means if we look at these guys, this becomes our new base, our new bronze of Larry base. Because it now has the potential to gain an H ion because it has that electron pair on the O atom. This guy now has an extra H ion. So it has the potential to donate one. So this guy becomes our bronchit Larry acid. |
Conjugate Acid-Base Pairs .txt | This guy now has an extra H ion. So it has the potential to donate one. So this guy becomes our bronchit Larry acid. 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. So let's define conjugate acid base pairs. 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. |
Conjugate Acid-Base Pairs .txt | 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. So let's define conjugate acid base pairs. 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. So let's go back to our above system. So we have an acid loser than H ion becoming a base. So this acid and this base are the conjugate acid base pairs. |
Conjugate Acid-Base Pairs .txt | So let's go back to our above system. So we have an acid loser than H ion becoming a base. So this acid and this base are the conjugate acid base pairs. Likewise, this base gains an H becomes a new acid. So this base and this acid are the conjugate acid base pairs. 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. |
Conjugate Acid-Base Pairs .txt | Likewise, this base gains an H becomes a new acid. So this base and this acid are the conjugate acid base pairs. 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. For example, let's look at another reaction in which an acid, a bronsolaric acid reacts with a base water. What will happen is this has the potential to gain an H. So it will give off the H.
And the lone pair of electrons on the base will take that H forming our new conjugate acid plus our new conjugate base. So this acid and this base are conjugate acid base pairs. |
Conjugate Acid-Base Pairs .txt | For example, let's look at another reaction in which an acid, a bronsolaric acid reacts with a base water. What will happen is this has the potential to gain an H. So it will give off the H.
And the lone pair of electrons on the base will take that H forming our new conjugate acid plus our new conjugate base. So this acid and this base are conjugate acid base pairs. And this base and this acid are conjugate acid base pairs. 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. You'll never find both members on one side. |
Conjugate Acid-Base Pairs .txt | And this base and this acid are conjugate acid base pairs. 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. You'll never find both members on one side. For example, this guy and this guy are found on different sides. And this guy and this guy are found different sides, just like this acid and this new base are found on different sides. And this base and this acid are found on different sides, so this always holds true. |
Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt | In this lecture, we're going to talk about four important periodic trends atomic radius, ionization energy, electronegativity, and electron affinity of atoms. Now, let's begin with atomic radius. So what is an atomic radius? Well, it's exactly what you think it is. 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. So, for this atom, our radius is the black line. |
Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt | Well, it's exactly what you think it is. 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. So, for this atom, our radius is the black line. 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? For example, let's take the following period. Let's begin with lithium and go all the way up to four. |
Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt | 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? For example, let's take the following period. Let's begin with lithium and go all the way up to four. What happens to our atomic radius? Well, we see that atomic radius decreases as we go from lithium to fluorine. Why is that? |
Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt | What happens to our atomic radius? Well, we see that atomic radius decreases as we go from lithium to fluorine. Why is that? Well, it's because of two things. First, the number of protons or number of protons found in our nucleus increases as we go from lithium to fluorine. And second, the number of electrons found on our most electron shell also increases. |
Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt | Well, it's because of two things. First, the number of protons or number of protons found in our nucleus increases as we go from lithium to fluorine. And second, the number of electrons found on our most electron shell also increases. And this means, according to Coulomb's law, the force also increases. In other words, the force with which the protons pull the outermost electrons increases. And this means that our effective nuclear charge on our atom increases. |
Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt | And this means, according to Coulomb's law, the force also increases. In other words, the force with which the protons pull the outermost electrons increases. And this means that our effective nuclear charge on our atom increases. And if the force is stronger, so the protons are pulling our outermost electrons with a greater force, that means our radius will decrease. The difference between the center, the nucleus and the outermost electron will decrease as we go across the period. 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. |
Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt | And if the force is stronger, so the protons are pulling our outermost electrons with a greater force, that means our radius will decrease. The difference between the center, the nucleus and the outermost electron will decrease as we go across the period. 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. So now let's talk about a group. What happens as we go from top of the group to the bottom of the group? So let's look at the following group. |
Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt | So now let's talk about a group. What happens as we go from top of the group to the bottom of the group? So let's look at the following group. Let's begin with lithium and go to sodium, then potassium, and so on. Well, as we go down the group, our atomic radius tends to increase. And this is because with which atom we add a new energy shell. |
Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt | Let's begin with lithium and go to sodium, then potassium, and so on. Well, as we go down the group, our atomic radius tends to increase. And this is because with which atom we add a new energy shell. So let's look at the following two atoms. Let's look at lithium and let's look at sodium. Sodium is right below lithium on the same group on the periodic table. |
Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt | So let's look at the following two atoms. Let's look at lithium and let's look at sodium. Sodium is right below lithium on the same group on the periodic table. 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. One S, two F and three S.
Now, this addition of the three S means that our atom will grow in size, will enlarge. Where this guy, the atomos guy, is the three F. Shell. |
Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt | 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. One S, two F and three S.
Now, this addition of the three S means that our atom will grow in size, will enlarge. Where this guy, the atomos guy, is the three F. Shell. 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. And that's exactly what we see. 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. |
Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt | 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. And that's exactly what we see. 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. So that's atomic radius. Now let's look at the ionization energy of our atoms. So what is ionization energy? |
Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt | So that's atomic radius. Now let's look at the ionization energy of our atoms. So what is ionization energy? Well, electrons don't simply come off the atoms by themselves. Remember, electrons are held together by electrostatic force that comes from the positively charged nucleus and the negatively charged electrons. So something must pull those electrons away. |
Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt | Well, electrons don't simply come off the atoms by themselves. Remember, electrons are held together by electrostatic force that comes from the positively charged nucleus and the negatively charged electrons. So something must pull those electrons away. In other words, work or energy must be inputted into our system to pull that electron off. So therefore, we can define our ionization energy to be the energy required to pull off that electron. That outermost electron. |
Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt | In other words, work or energy must be inputted into our system to pull that electron off. So therefore, we can define our ionization energy to be the energy required to pull off that electron. That outermost electron. Now more than one electron can be pulled off. For example, calcium. Calcium in its neutral state, can take away two electrons to become calcium plus two. |
Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt | Now more than one electron can be pulled off. For example, calcium. Calcium in its neutral state, can take away two electrons to become calcium plus two. So that means some atoms can pull away or can give off more than one electron. 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. 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. |
Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt | So that means some atoms can pull away or can give off more than one electron. 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. 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. And we see that as we go across a period, our ionization energy of our atom tends to increase. And to explain that, let's look at Coulomb's Law. 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. |
Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt | And we see that as we go across a period, our ionization energy of our atom tends to increase. And to explain that, let's look at Coulomb's Law. 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. Now what happens as we move, for example, from lithium to fluorine? We already said that our effective nuclear charge tends to increase as we go from left to right. So fluorine has the highest force. |
Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt | Now what happens as we move, for example, from lithium to fluorine? We already said that our effective nuclear charge tends to increase as we go from left to right. So fluorine has the highest force. In other words, the protons found in the nucleus. Pull those electrons on the outermost electron shell with a lot of force, much more force than lithium or beryllium or boron or carbon. And that means it's going to require much more energy to pull those outermost electrons off. |
Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt | In other words, the protons found in the nucleus. Pull those electrons on the outermost electron shell with a lot of force, much more force than lithium or beryllium or boron or carbon. And that means it's going to require much more energy to pull those outermost electrons off. And that's exactly why as we go across the period from lithium to fluorine, our ionization energy tends to increase. Because as we go this way, we have a higher effective nuclear charge, which means we have a greater force. And also take this into account. |
Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt | And that's exactly why as we go across the period from lithium to fluorine, our ionization energy tends to increase. Because as we go this way, we have a higher effective nuclear charge, which means we have a greater force. And also take this into account. As we go across, our atomic radius decreases, and that means our denominator. Our R also increases. So we see that our cues increase, our Rs decrease. |
Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt | As we go across, our atomic radius decreases, and that means our denominator. Our R also increases. So we see that our cues increase, our Rs decrease. And whenever the denominator decreases, that means our force tends to increase. 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. So therefore, as we go from left to right, our ionization energy also increases. |
Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt | And whenever the denominator decreases, that means our force tends to increase. 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. So therefore, as we go from left to right, our ionization energy also increases. How Bad? When we go down a group. Well, when we go down the group, our atomic radius increases. |
Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt | How Bad? When we go down a group. Well, when we go down the group, our atomic radius increases. 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. So our R also increases. And if there are increases, our denominators increase. |
Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt | 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. So our R also increases. And if there are increases, our denominators increase. And that means our force is less. So as we go down a group, our ionization energy tends to decrease. So to wrap up, basically, the higher your ionization energy is, the less likely you are to give up electrons. |
Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt | And that means our force is less. So as we go down a group, our ionization energy tends to decrease. So to wrap up, basically, the higher your ionization energy is, the less likely you are to give up electrons. And we'll see that this directly translates into something called electronegativity. So let's look at the third periodic trend called electronegativity. Now, electronegativity is simply the ability of atoms to accept or attract other electrons. |
Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt | And we'll see that this directly translates into something called electronegativity. So let's look at the third periodic trend called electronegativity. Now, electronegativity is simply the ability of atoms to accept or attract other electrons. And we see that as we go from left to right, across the period, from Lithium to Fluorine, our Electronegativity increases. So let's examine why. Let's look at atomic structure and the electron configuration of lithium and compare to that of fluorine. |
Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt | And we see that as we go from left to right, across the period, from Lithium to Fluorine, our Electronegativity increases. So let's examine why. Let's look at atomic structure and the electron configuration of lithium and compare to that of fluorine. Now, lithium has three electrons and three protons. 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. Now let's look at the fluorine. |
Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt | Now, lithium has three electrons and three protons. 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. Now let's look at the fluorine. Fluorine has nine protons in its nucleus. While two electrons are found in the inner shell, seven electrons are found on the outer shell. And that means because we have a higher nuclear or effective nuclear charge, we have a higher force. |
Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt | Fluorine has nine protons in its nucleus. While two electrons are found in the inner shell, seven electrons are found on the outer shell. And that means because we have a higher nuclear or effective nuclear charge, we have a higher force. 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. And so that means if we place some arbitrary electron equidistant between these two atoms what? We see that this fluorine will pull this electron with much more force than this guy. |
Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt | 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. And so that means if we place some arbitrary electron equidistant between these two atoms what? We see that this fluorine will pull this electron with much more force than this guy. 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. 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? Well, as we go from top to bottom, our atomic radius increases. |
Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt | 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. 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? Well, as we go from top to bottom, our atomic radius increases. So our force with which our protons in the nucleus pull those electrons decreases. Because remember, force, according to Coulomb's law, is equal to K times q one times q two over r two. So our denominator increases, decreasing our force. |
Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt | So our force with which our protons in the nucleus pull those electrons decreases. Because remember, force, according to Coulomb's law, is equal to K times q one times q two over r two. So our denominator increases, decreasing our force. And so, therefore, as we go from top to bottom, our electronegativity decreases. Now for noble gases. Electro. |
Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt | And so, therefore, as we go from top to bottom, our electronegativity decreases. Now for noble gases. Electro. Negativity is undefined. And that's because in Noble gas structure, the electron configuration is perfect. And what noble gases can't accept any more electrons? |
Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt | Negativity is undefined. And that's because in Noble gas structure, the electron configuration is perfect. And what noble gases can't accept any more electrons? Because notice that this twopie orbital can accept one more electron. And that's exactly why fluorine can accept one more electron. 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. |
Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt | Because notice that this twopie orbital can accept one more electron. And that's exactly why fluorine can accept one more electron. 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. So let's look at our final periodic trend called electron affinity. Now. Electron affinity is the amount of energy released when an atom gains an electron. |
Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt | So let's look at our final periodic trend called electron affinity. Now. Electron affinity is the amount of energy released when an atom gains an electron. Remember, the only way to take an electron away from the outer shell of an atom is to apply work, is to input energy. Because work must be done against the force of the protons in the nucleus attracting those electrons, those outer electrons. So that means the reverse must be the following whenever an electron or whenever an atom gains an electron energy must be released. |
Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt | Remember, the only way to take an electron away from the outer shell of an atom is to apply work, is to input energy. Because work must be done against the force of the protons in the nucleus attracting those electrons, those outer electrons. So that means the reverse must be the following whenever an electron or whenever an atom gains an electron energy must be released. And that's exactly what happens when Fluorine, for example, gains electrons. When fluorine goes from a neutral molecule, gains an electron to form an anion, it loses energy. The energy level of the outer shell is lower. |
Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt | And that's exactly what happens when Fluorine, for example, gains electrons. When fluorine goes from a neutral molecule, gains an electron to form an anion, it loses energy. The energy level of the outer shell is lower. And therefore this molecule, this anion is more stable than the neutral counterpart. So this reaction going this way is exothermic. Now. |
Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt | And therefore this molecule, this anion is more stable than the neutral counterpart. So this reaction going this way is exothermic. Now. 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. And that means this guy, this reaction is more exothermic for fluorine than for lithium. In other words, whenever our fluorine gains electrons, it becomes stable and it loses a lot of energy. |
Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt | 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. And that means this guy, this reaction is more exothermic for fluorine than for lithium. In other words, whenever our fluorine gains electrons, it becomes stable and it loses a lot of energy. On the contrary, whenever this guy gains electrons, the reaction for this guy is endothermic. Because this guy, the lithium in the neutral state is more stable than the anion than lithium minus one. And that's exactly what we mean by electron affinity. |
Atomic Radius, Ionization Energy, Electronegativity and Electron Affinity .txt | On the contrary, whenever this guy gains electrons, the reaction for this guy is endothermic. Because this guy, the lithium in the neutral state is more stable than the anion than lithium minus one. And that's exactly what we mean by electron affinity. Now. Likewise, as we go from top to bottom on our group in group, on the period our electron affinity decreases. And that's because our atomic radius increases as we go from top to bottom. |
Oxidation-Reduction Reactions .txt | Now, the atom that gains the electrons becomes more negative and is said to be reduced. The atom that loses the electrons is said to be more positive and is said to be oxidized. So let's look at atoms A and B. Suppose atom A loses an electron, while atom B gains that same electron. That means our charge of A goes from A neutral charge to A plus one charge. It loses an electron, while atom B gains an electron. |
Oxidation-Reduction Reactions .txt | Suppose atom A loses an electron, while atom B gains that same electron. That means our charge of A goes from A neutral charge to A plus one charge. It loses an electron, while atom B gains an electron. So Its charge goes from A neutral charge to a negative one charge. So species A or atom A is said to be oxidized, while atom B is set to be reduced. Now, we can also look at it another way. |
Oxidation-Reduction Reactions .txt | So Its charge goes from A neutral charge to a negative one charge. So species A or atom A is said to be oxidized, while atom B is set to be reduced. Now, we can also look at it another way. Atom A is a reducing agent. Why? Well, because it reduces atom B. |
Oxidation-Reduction Reactions .txt | Atom A is a reducing agent. Why? Well, because it reduces atom B. It makes this atom more negative. 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. 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. |
Oxidation-Reduction Reactions .txt | It makes this atom more negative. 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. 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. 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. So on this side, our H two is in its atomic state. It's in its elemental state, and so is oxygen. |
Oxidation-Reduction Reactions .txt | 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. So on this side, our H two is in its atomic state. It's in its elemental state, and so is oxygen. That means they both have A charge of zero. Now, in this case, our oxygen becomes negative two, and our H becomes a positive two. And two H's cause A positive two charge. |
Oxidation-Reduction Reactions .txt | That means they both have A charge of zero. Now, in this case, our oxygen becomes negative two, and our H becomes a positive two. And two H's cause A positive two charge. So our overall charge is zero. But each atom gains or loses electrons. So let's see what happens. |
Oxidation-Reduction Reactions .txt | So our overall charge is zero. But each atom gains or loses electrons. So let's see what happens. So, our H atom is the reducing agent, and it loses electrons, which means it's oxidized. And that loss of electrons, those electrons are transferred to our oxygen molecule, and that means our oxygen molecule is reduced. So this oxygen molecule is the oxidizing agent because it gains those electrons. |
Order of Reactions .txt | 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. Now, we already spoke about what the rate law was. The rate law of any reaction is a mathematical representation of the relationship between the concentration of the reactants and our rate of reaction. 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. Now, this A represents the order of our reactants. And since the only reactant is the x reactant, this A represents the order of the entire reaction. |
Order of Reactions .txt | 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. Now, this A represents the order of our reactants. And since the only reactant is the x reactant, this A represents the order of the entire reaction. Now, my question is how do we determine the order of our reaction, namely A and our rate constant KF? Well, one way to do it, as we saw, is to determine using experimental results. 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. |
Order of Reactions .txt | Now, my question is how do we determine the order of our reaction, namely A and our rate constant KF? Well, one way to do it, as we saw, is to determine using experimental results. 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. And using that this guy and our concentration, we can then find our KAP. Well, that's one way to do it. A second way to do it is with graphing. |
Order of Reactions .txt | And using that this guy and our concentration, we can then find our KAP. Well, that's one way to do it. A second way to do it is with graphing. So we can graph concentration of reactants against time or progress of reaction. Now, there are three main graphs that we can get. Now let's look at the first one. |
Order of Reactions .txt | So we can graph concentration of reactants against time or progress of reaction. Now, there are three main graphs that we can get. Now let's look at the first one. The first one is known as the 0th order of our reaction. And that means our A is equal to zero. So this exponent A is zero and hence 0th order of our react. |
Order of Reactions .txt | The first one is known as the 0th order of our reaction. And that means our A is equal to zero. So this exponent A is zero and hence 0th order of our react. Now let's recall what the rate of reaction is. Well, the rate of any reaction or reactant is given by the following formula. Since we're going from reactants to products, our reactant concentration is decreasing, so the rate is negative. |
Order of Reactions .txt | Now let's recall what the rate of reaction is. Well, the rate of any reaction or reactant is given by the following formula. Since we're going from reactants to products, our reactant concentration is decreasing, so the rate is negative. Change in x of concentration x divided by change in time is equal to our rate of forward. So k times our concentration of x. Now, since we're dealing with A equals zero, the zeros order, we plug in our zero for the exponent A. |
Order of Reactions .txt | Change in x of concentration x divided by change in time is equal to our rate of forward. So k times our concentration of x. Now, since we're dealing with A equals zero, the zeros order, we plug in our zero for the exponent A. That means this guy, the x will go to zero. So let's rearrange this a bit. Let's bring the negative over here. |
Order of Reactions .txt | That means this guy, the x will go to zero. So let's rearrange this a bit. Let's bring the negative over here. 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. Now let's represent this guy and this guy following way. So the final concentration minus the initial concentration equals negative k in parentheses time final minus time initial. |
Order of Reactions .txt | 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. Now let's represent this guy and this guy following way. So the final concentration minus the initial concentration equals negative k in parentheses time final minus time initial. But what is time initial? Time initial is time zero. So this guy is zero. |
Order of Reactions .txt | But what is time initial? Time initial is time zero. So this guy is zero. So let's go here. Now, change in concentration of final minus change in concentration of initial gives you negative k times t final because this guy becomes zero. 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. |
Order of Reactions .txt | So let's go here. Now, change in concentration of final minus change in concentration of initial gives you negative k times t final because this guy becomes zero. 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. And notice that this equation has the same form as y equals MX plus b. This is our general equation for a line. And that means if we plot this guy, we will get a line. |
Order of Reactions .txt | And notice that this equation has the same form as y equals MX plus b. This is our general equation for a line. And that means if we plot this guy, we will get a line. So this is our y number, this is our Y intercept, this is our x value and this is our slope. 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
comma concentration of initial because it's time to zero, we plug in t zero and we get simply this guy equals this guy. That's exactly what this guy is. |
Order of Reactions .txt | So this is our y number, this is our Y intercept, this is our x value and this is our slope. 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
comma concentration of initial because it's time to zero, we plug in t zero and we get simply this guy equals this guy. That's exactly what this guy is. This is our initial concentration of our reactor. Now the slope represents negative k, this is our slope. 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. |
Order of Reactions .txt | This is our initial concentration of our reactor. Now the slope represents negative k, this is our slope. 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. And that's how we find our K.
Now, 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. That means our A must be one. 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. |
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