alexignite/chemset1 · Datasets at Hugging Face

title stringlengths 8 78	text stringlengths 3 643
Polyprotic Acids .txt	So the concentration of this guy times the concentration of this guy divided by the concentration of the reaction of this guy.
Polyprotic Acids .txt	And we said that if our Ka value is high, if it's bigger than one, that means our acid is a strong acid.
Polyprotic Acids .txt	And if our Ka is low, if it's less than one, we're dealing with a weak acid.
Polyprotic Acids .txt	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.
Polyprotic Acids .txt	So therefore, if our Ka is high, that means the concentration of these guys is high and the concentration of this guy is low.
Polyprotic Acids .txt	And that makes sense.
Polyprotic Acids .txt	Now let's look at polyphonic acid.
Polyprotic Acids .txt	Polyportic acids are those acids that can donate more than one H plus ion.
Polyprotic Acids .txt	So let's look at a few examples.
Polyprotic Acids .txt	Sulfuric acid, hydronium ion, phosphoric acid and carbonic acid are all examples of polyphonic acids.
Polyprotic Acids .txt	And that's because they all have more than two or more than one H plus ion that they can donate.
Polyprotic Acids .txt	This guy has three H plus ions that he can donate.
Polyprotic Acids .txt	So in the same way that we spoke about ionization reactions of monopolytic acids, we can also talk about ionization reactions of polyphotic acids.
Polyprotic Acids .txt	So let's look at a hypothetical example of a polyphotic acid, h two A.
Polyprotic Acids .txt	Now, for H two A, we're not going to have one reaction.
Polyprotic Acids .txt	We're going to have two reactions.
Polyprotic Acids .txt	And that's because we have two potential HS that can be lost to our environment.
Polyprotic Acids .txt	So H two A will react in water to produce hydronium and our conjugate base.
Polyprotic Acids .txt	Now let's look at this conjugate base.
Polyprotic Acids .txt	This conjugate base can either go two ways.
Polyprotic Acids .txt	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.
Polyprotic Acids .txt	Now, the same way we spoke about Ka or acidization constants for monoprotic acids, we can also talk about Ka's about polyproteic acids.
Polyprotic Acids .txt	Except now we're not going to have one Ka.
Polyprotic Acids .txt	We're going to have more than one Ka.
Polyprotic Acids .txt	Each Ka represents a single reaction.
Polyprotic Acids .txt	So, for this particular polyphonic acids, we have two reactions.
Polyprotic Acids .txt	So we have two ka's.
Polyprotic Acids .txt	And normally, the first ka will have a higher value than the second ka.
Polyprotic Acids .txt	And that's because of the following fact.
Polyprotic Acids .txt	Now, when we go from this acid to this base, we get a negative one charge.
Polyprotic Acids .txt	When we go from this acid to this base, we get a negative two charge.
Polyprotic Acids .txt	Which one of these is less stable?
Polyprotic Acids .txt	Well, this guy.
Polyprotic Acids .txt	And that's because the more charge we have, the less stability.
Polyprotic Acids .txt	And so this guy will not want to exist by itself.
Polyprotic Acids .txt	This guy will want to exist in this form.
Polyprotic Acids .txt	And so our reaction for this guy is favored this way.
Polyprotic Acids .txt	And that's why our ka is much smaller for this reaction than this reaction.
Polyprotic Acids .txt	And in fact, this reaction is 10,000 times more likely than this reaction.
Polyprotic Acids .txt	So, in the same way that we spoke about titration curves of monopolic acids, we can also talk about titration curves of polyphonic acids.
Polyprotic Acids .txt	So here's our titration curve.
Polyprotic Acids .txt	While the Y axis is PH and the X axis is volume based at it.
Polyprotic Acids .txt	Now, this curve is for our hypothetical phypotic acid, h two A.
Polyprotic Acids .txt	Now, this guy will have not one equivalence point, but two equivalence points.
Polyprotic Acids .txt	And let's look at what each represents.
Polyprotic Acids .txt	Let's look at the first one.
Polyprotic Acids .txt	What the first one represents is it's the point at which all of this guy has been neutralized to this guy.
Polyprotic Acids .txt	So there's no more of this guy, and 100% of our solution is in this form at this point.
Polyprotic Acids .txt	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.
Polyprotic Acids .txt	And at this point, as a second equivalence point, all of our solution is in this form.
Polyprotic Acids .txt	So, at this point, we notice we have a very high PH.
Polyprotic Acids .txt	And a high PH means we're in a basic environment.
Polyprotic Acids .txt	And basic means we don't have a lot of H plus ions.
Polyprotic Acids .txt	So why is it that at this point, this guy really wants to associate into this guy?
Polyprotic Acids .txt	Well, let's examine why.
Polyprotic Acids .txt	Well, in our high PH or a basic environment, we don't have a lot of H plus, so this guy decreases.
Polyprotic Acids .txt	So to compensate that, according to Alicia clear principle, this guy will dissociate.
Polyprotic Acids .txt	So our equilibrium will be favored this way.
Polyprotic Acids .txt	And that's exactly why at a high PH, our reaction goes this way.
Polyprotic Acids .txt	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.
Reaction Rates and Rate Law .txt	Talk about rate of reactions and see exactly how the two are related.
Reaction Rates and Rate Law .txt	So, let's look at the following elementary equation.
Reaction Rates and Rate Law .txt	Now, we begin with two reactants, x and Y and they convert into W and Z.
Reaction Rates and Rate Law .txt	What elementary simply means is that they convert from reactants to products in a single step.
Reaction Rates and Rate Law .txt	Elementary reactions are some of the most basic reactions out there.
Reaction Rates and Rate Law .txt	Now notice that A-B-C and D are coefficients of each respective molecule and they represent the number of molecules or moles.
Reaction Rates and Rate Law .txt	Now, rates of reactions tell you how quickly reactants become products, so how quickly x and y become W and Z.
Reaction Rates and Rate Law .txt	In other words, the rate can be found by the change in concentration of reactants over some given time.
Reaction Rates and Rate Law .txt	Now, notice that we go from a positive amount or some amount to a small amount.
Reaction Rates and Rate Law .txt	So over time, our x and y will disappear.
Reaction Rates and Rate Law .txt	So therefore, the rate of these guys are negative because remember, we're subtracting our initial from final.
Reaction Rates and Rate Law .txt	An initial concentration of x is larger than final concentration of x.
Reaction Rates and Rate Law .txt	The final will be less.
Reaction Rates and Rate Law .txt	We'll have less x and y at the end because some of these guys will convert to W and Z.
Reaction Rates and Rate Law .txt	So once again, the rate or average rate of x is negative change in concentration of x over time.
Reaction Rates and Rate Law .txt	Now, time is also multiplied by A.
Reaction Rates and Rate Law .txt	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.
Reaction Rates and Rate Law .txt	The negative change in concentration of y over BT gives you the rate of disappearance of Y.
Reaction Rates and Rate Law .txt	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.
Reaction Rates and Rate Law .txt	Now, let's look at the factors affecting our reaction rates.
Reaction Rates and Rate Law .txt	So, we already said that temperature affects our rates of reaction because it affects our rate constant.
Reaction Rates and Rate Law .txt	Now, if the rate constant increases, then our rate of reaction increases.
Reaction Rates and Rate Law .txt	And we'll see why at the end of this lecture.
Reaction Rates and Rate Law .txt	But notice that temperature increasing.
Reaction Rates and Rate Law .txt	Temperature affects rate constant by affecting the kinetic energy of molecules.
Reaction Rates and Rate Law .txt	On average, molecules will have higher kinetic energy and a higher temperature.
Reaction Rates and Rate Law .txt	And that means they will be more likely to overcome the activation energy barrier and become our products.
Reaction Rates and Rate Law .txt	Now, concentrations we see using these formulas affect or increase our rates.
Reaction Rates and Rate Law .txt	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.
Reaction Rates and Rate Law .txt	Now, pressure also has an effect on rates and we'll see how in another video.
Reaction Rates and Rate Law .txt	Now we spoke about elementary reactions in which reactants become products in a single step.
Reaction Rates and Rate Law .txt	Now, there are also multi step reactions and those include many different steps, intermediate steps.
Reaction Rates and Rate Law .txt	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.
Reaction Rates and Rate Law .txt	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.
Reaction Rates and Rate Law .txt	Now this guy is out intermediate.
Reaction Rates and Rate Law .txt	Now, as long as the concentration of this guy is kept relatively low, we can approximate using these formulas here.
Reaction Rates and Rate Law .txt	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.
Reaction Rates and Rate Law .txt	Now let's talk about the rate law.
Reaction Rates and Rate Law .txt	The rate law is a mathematical representation that summarizes relationship between reactants and reaction rate.
Reaction Rates and Rate Law .txt	And it also builds a relationship between our rate constant and our rate of reaction.

Polyprotic Acids .txt

So the concentration of this guy times the concentration of this guy divided by the concentration of the reaction of this guy.

Polyprotic Acids .txt

And we said that if our Ka value is high, if it's bigger than one, that means our acid is a strong acid.

Polyprotic Acids .txt

And if our Ka is low, if it's less than one, we're dealing with a weak acid.

Polyprotic Acids .txt

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.

Polyprotic Acids .txt

So therefore, if our Ka is high, that means the concentration of these guys is high and the concentration of this guy is low.

Polyprotic Acids .txt

And that makes sense.

Polyprotic Acids .txt

Now let's look at polyphonic acid.

Polyprotic Acids .txt

Polyportic acids are those acids that can donate more than one H plus ion.

Polyprotic Acids .txt

So let's look at a few examples.

Polyprotic Acids .txt

Sulfuric acid, hydronium ion, phosphoric acid and carbonic acid are all examples of polyphonic acids.

Polyprotic Acids .txt

And that's because they all have more than two or more than one H plus ion that they can donate.

Polyprotic Acids .txt

This guy has three H plus ions that he can donate.

Polyprotic Acids .txt

So in the same way that we spoke about ionization reactions of monopolytic acids, we can also talk about ionization reactions of polyphotic acids.

Polyprotic Acids .txt

So let's look at a hypothetical example of a polyphotic acid, h two A.

Polyprotic Acids .txt

Now, for H two A, we're not going to have one reaction.

Polyprotic Acids .txt

We're going to have two reactions.

Polyprotic Acids .txt

And that's because we have two potential HS that can be lost to our environment.

Polyprotic Acids .txt

So H two A will react in water to produce hydronium and our conjugate base.

Polyprotic Acids .txt

Now let's look at this conjugate base.

Polyprotic Acids .txt

This conjugate base can either go two ways.

Polyprotic Acids .txt

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.

Polyprotic Acids .txt

Now, the same way we spoke about Ka or acidization constants for monoprotic acids, we can also talk about Ka's about polyproteic acids.

Polyprotic Acids .txt

Except now we're not going to have one Ka.

Polyprotic Acids .txt

We're going to have more than one Ka.

Polyprotic Acids .txt

Each Ka represents a single reaction.

Polyprotic Acids .txt

So, for this particular polyphonic acids, we have two reactions.

Polyprotic Acids .txt

So we have two ka's.

Polyprotic Acids .txt

And normally, the first ka will have a higher value than the second ka.

Polyprotic Acids .txt

And that's because of the following fact.

Polyprotic Acids .txt

Now, when we go from this acid to this base, we get a negative one charge.

Polyprotic Acids .txt

When we go from this acid to this base, we get a negative two charge.

Polyprotic Acids .txt

Which one of these is less stable?

Polyprotic Acids .txt

Well, this guy.

Polyprotic Acids .txt

And that's because the more charge we have, the less stability.

Polyprotic Acids .txt

And so this guy will not want to exist by itself.

Polyprotic Acids .txt

This guy will want to exist in this form.

Polyprotic Acids .txt

And so our reaction for this guy is favored this way.

Polyprotic Acids .txt

And that's why our ka is much smaller for this reaction than this reaction.

Polyprotic Acids .txt

And in fact, this reaction is 10,000 times more likely than this reaction.

Polyprotic Acids .txt

So, in the same way that we spoke about titration curves of monopolic acids, we can also talk about titration curves of polyphonic acids.

Polyprotic Acids .txt

So here's our titration curve.

Polyprotic Acids .txt

While the Y axis is PH and the X axis is volume based at it.

Polyprotic Acids .txt

Now, this curve is for our hypothetical phypotic acid, h two A.

Polyprotic Acids .txt

Now, this guy will have not one equivalence point, but two equivalence points.

Polyprotic Acids .txt

And let's look at what each represents.

Polyprotic Acids .txt

Let's look at the first one.

Polyprotic Acids .txt

What the first one represents is it's the point at which all of this guy has been neutralized to this guy.

Polyprotic Acids .txt

So there's no more of this guy, and 100% of our solution is in this form at this point.

Polyprotic Acids .txt

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.

Polyprotic Acids .txt

And at this point, as a second equivalence point, all of our solution is in this form.

Polyprotic Acids .txt

So, at this point, we notice we have a very high PH.

Polyprotic Acids .txt

And a high PH means we're in a basic environment.

Polyprotic Acids .txt

And basic means we don't have a lot of H plus ions.

Polyprotic Acids .txt

So why is it that at this point, this guy really wants to associate into this guy?

Polyprotic Acids .txt

Well, let's examine why.

Polyprotic Acids .txt

Well, in our high PH or a basic environment, we don't have a lot of H plus, so this guy decreases.

Polyprotic Acids .txt

So to compensate that, according to Alicia clear principle, this guy will dissociate.

Polyprotic Acids .txt

So our equilibrium will be favored this way.

Polyprotic Acids .txt

And that's exactly why at a high PH, our reaction goes this way.

Polyprotic Acids .txt

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.