ceaglex/VisualTTS_Chem · Datasets at Hugging Face

text stringlengths 19 206
oqN1aemQnu0-012\|Every point on this line, the solid and the liquid are in equilibrium.
oqN1aemQnu0-013\|Now, for carbon dioxide, it turns out that common equilibrium that we observe is the solid gas, or sublimation equilibrium.
oqN1aemQnu0-016\|And if I bring it here to the desktop, that's solid carbon dioxide.
oqN1aemQnu0-017\|And that vibrating that you hear is the gas subliming off the carbon dioxide.
oqN1aemQnu0-018\|That gas phase provides a cushion of gas.
oqN1aemQnu0-020\|That's the sublimation of carbon dioxide.
oqN1aemQnu0-021\|Now, let's talk about some other regions on the phase diagram.
oqN1aemQnu0-022\|Interestingly, there's a point where all three of the solid, liquid, and gas phases intersect.
oqN1aemQnu0-023\|This is called the triple point.
oqN1aemQnu0-027\|A particle can move from the solid phase to the liquid phase, liquid to solid, or solid to gas independently.
oqN1aemQnu0-028\|All three are equally likely at the triple point.
oqN1aemQnu0-029\|We also have the critical point.
oqN1aemQnu0-035\|Now, water is one of the only substances where the slope of the solid-liquid slopes backwards.
oqN1aemQnu0-036\|Now, that's interesting.
oqN1aemQnu0-037\|That says if you compress solid water, you go up in pressure-- so here's a solid water point.
oqN1aemQnu0-038\|I go up in pressure.
oqN1aemQnu0-039\|It should turn into the liquid.
oqN1aemQnu0-040\|And that's counterintuitive.
oqN1aemQnu0-041\|Most things, when you increase the pressure, you should continue to favor the solid, the more tightly compact phase of matter.
oqN1aemQnu0-042\|Turns out for water, the solid is not the most tightly compact phase.
oqN1aemQnu0-043\|The solid is actually slightly less dense than the liquid.
oqN1aemQnu0-044\|And we know that.
oqN1aemQnu0-045\|We've seen solid ice float on top of liquid ice.
oqN1aemQnu0-046\|In fact, it's the most common solid-liquid phase transition we know about.
oqN1aemQnu0-047\|So when we think about it, you'd think, oh, maybe all solids float on their liquids.
oqN1aemQnu0-048\|It's actually the reverse.
oqN1aemQnu0-049\|Just because that's a common substance, water, and we see the solid floating on the liquid, we get the impression that that's common.
oqN1aemQnu0-050\|It's actually the least common interaction.
oqN1aemQnu0-051\|Most solids sink in their own liquid.
oqN1aemQnu0-055\|So very near 0 Celsius, but a fraction of an atmosphere.
oqN1aemQnu0-056\|There are 760 torr in one atmosphere.
OlehBTSyPDA-000\|Let's do a calculation that's a titration calculation.
OlehBTSyPDA-002\|The question is, what is the pH after those two are mixed?
OlehBTSyPDA-003\|So I can think about this as a titration.
OlehBTSyPDA-005\|The question is, how far along on the titration curve does this addition of strong base take me?
OlehBTSyPDA-006\|Does it take me to the center of the buffer region?
OlehBTSyPDA-007\|Is it enough to take me to the equivalence point?
OlehBTSyPDA-009\|We have HAc plus water, forming acetic acid and H3O plus.
OlehBTSyPDA-010\|That's one of the equilibria we have to deal with for this problem.
OlehBTSyPDA-011\|But we want to find out, well, what are the initial conditions?
OlehBTSyPDA-012\|How much HAc, how much Ac minus, and how much H3O plus are there at a point?
OlehBTSyPDA-013\|And then we'll allow the equilibria to expand.
OlehBTSyPDA-014\|And this is how you do equilibrium calculations.
OlehBTSyPDA-015\|You find a point that you can nail down.
OlehBTSyPDA-016\|Say, OK, these will be my starting conditions.
OlehBTSyPDA-017\|And then you apply the equilibrium to see how it shifts from that one point.
OlehBTSyPDA-018\|And that's the great thing about equilibria, they approach the same equilibria no matter where you start from.
OlehBTSyPDA-019\|So as long as you can nail down one point that you know and then apply equilibrium from there, you're going to get to the correct equilibrium condition.
OlehBTSyPDA-023\|Well, molarity times volume is the number of moles.
OlehBTSyPDA-024\|So 0.01 moles of acetic acid.
OlehBTSyPDA-025\|Now this is assuming no dissociation.
OlehBTSyPDA-026\|That's fine.
OlehBTSyPDA-027\|I can choose any point along my equilibrium to be my starting point.
OlehBTSyPDA-033\|And I choose that because the weak acid reacts completely with the strong base.
OlehBTSyPDA-034\|That's a very strong reaction to favor the products.
OlehBTSyPDA-038\|So that's not really an equilibrium, that one just goes all the way towards products.
OlehBTSyPDA-039\|So if we start there and say, what happens after that occurs?
OlehBTSyPDA-040\|Are there an equilibrium in effect, that will calculate the pH of the solution.
OlehBTSyPDA-041\|So let's do that.
OlehBTSyPDA-042\|We'll say, these two will react completely.
OlehBTSyPDA-043\|So every mole of base will react with a mole of acid.
OlehBTSyPDA-044\|And I'll have-- this is essentially half of this.
OlehBTSyPDA-045\|So half of my base-- excuse me.
OlehBTSyPDA-046\|Half of my acid will react with this base, and I'll form 0.05 moles of the conjugate base.
OlehBTSyPDA-047\|So the acid reacts with the base to form the conjugate base.
OlehBTSyPDA-049\|Here, the acid reacting with the base to form the conjugate base.
OlehBTSyPDA-050\|In this case, I've added half the number of moles of HA that I originally had.
OlehBTSyPDA-052\|Half of these react, so I have equal concentrations essentially of this and this at this point in the titration.
OlehBTSyPDA-053\|So equal concentrations of these two.
OlehBTSyPDA-054\|Half of my acid has been converted into its conjugate base.
OlehBTSyPDA-055\|My OH minus concentration, it's gone to zero.
OlehBTSyPDA-056\|I've used up one for one.
OlehBTSyPDA-057\|One of those react with one of those, producing one of these.
OlehBTSyPDA-058\|So let's treat these now as the initial concentrations in an equilibrium calculation and see where that gets us.
OlehBTSyPDA-063\|But I know they're both in about 100 millimeters.
OlehBTSyPDA-064\|So I can convert these easily into concentrations, moles per liter.
OlehBTSyPDA-070\|Now this initial point is quite a ways into our calculation, but it's just the first point where I'm going to allow the equilibria to occur.
OlehBTSyPDA-071\|In all the previous steps, I've said they go to completion.
OlehBTSyPDA-072\|So now I'm at a point where everything has gone 100%, and I'm going to let the equilibria start to take over.
OlehBTSyPDA-073\|And I do that at this point.
OlehBTSyPDA-074\|And I can do that for equilibria at any point.
OlehBTSyPDA-075\|Choose a point, nail it down, say, this is where I'm going to start, and then let your equilibria table take over.
OlehBTSyPDA-076\|So the change to get to equilibrium is a little of this.
OlehBTSyPDA-077\|We'll dissociate.
OlehBTSyPDA-078\|And actually at this point, I'm not even sure.
OlehBTSyPDA-079\|I'm not sure if the equilibrium will go this way or this way.
OlehBTSyPDA-080\|I'm just going to assume a little of this goes away.
OlehBTSyPDA-081\|And if it does, it'll produce a little of this.
OlehBTSyPDA-082\|Since there's equal amounts, who knows?
OlehBTSyPDA-083\|Maybe it'll shift back this way.
OlehBTSyPDA-084\|I suspect it'll go this way though, because I think HAc is a strong enough acid to dissociate a little bit more.
OlehBTSyPDA-085\|That will produce a little H3O plus.
OlehBTSyPDA-086\|And I'm saying initially there was none of this.
OlehBTSyPDA-093\|So that's 10 to the minus 4.75.
OlehBTSyPDA-094\|4.75 is the Ka for acetic acid.
OlehBTSyPDA-102\|That is the H3O plus concentration.
OlehBTSyPDA-103\|And notice that I left the k like this, because I knew after I get the H3O plus concentration, I'm going to take minus log of it anyway.
OlehBTSyPDA-104\|So I'm going to go right back to the exponent.
OlehBTSyPDA-105\|So if I calculate the pH, that's minus log of 10 to the minus 4.75, which is 4.75.
OlehBTSyPDA-106\|So what I found is that the pH is numerically equal to the pKa.

oqN1aemQnu0-012|Every point on this line, the solid and the liquid are in equilibrium.

oqN1aemQnu0-013|Now, for carbon dioxide, it turns out that common equilibrium that we observe is the solid gas, or sublimation equilibrium.

oqN1aemQnu0-016|And if I bring it here to the desktop, that's solid carbon dioxide.

oqN1aemQnu0-017|And that vibrating that you hear is the gas subliming off the carbon dioxide.

oqN1aemQnu0-018|That gas phase provides a cushion of gas.

oqN1aemQnu0-020|That's the sublimation of carbon dioxide.

oqN1aemQnu0-021|Now, let's talk about some other regions on the phase diagram.

oqN1aemQnu0-022|Interestingly, there's a point where all three of the solid, liquid, and gas phases intersect.

oqN1aemQnu0-023|This is called the triple point.

oqN1aemQnu0-027|A particle can move from the solid phase to the liquid phase, liquid to solid, or solid to gas independently.

oqN1aemQnu0-028|All three are equally likely at the triple point.

oqN1aemQnu0-029|We also have the critical point.

oqN1aemQnu0-035|Now, water is one of the only substances where the slope of the solid-liquid slopes backwards.

oqN1aemQnu0-036|Now, that's interesting.

oqN1aemQnu0-037|That says if you compress solid water, you go up in pressure-- so here's a solid water point.

oqN1aemQnu0-038|I go up in pressure.

oqN1aemQnu0-039|It should turn into the liquid.

oqN1aemQnu0-040|And that's counterintuitive.

oqN1aemQnu0-041|Most things, when you increase the pressure, you should continue to favor the solid, the more tightly compact phase of matter.

oqN1aemQnu0-042|Turns out for water, the solid is not the most tightly compact phase.

oqN1aemQnu0-043|The solid is actually slightly less dense than the liquid.

oqN1aemQnu0-044|And we know that.

oqN1aemQnu0-045|We've seen solid ice float on top of liquid ice.

oqN1aemQnu0-046|In fact, it's the most common solid-liquid phase transition we know about.

oqN1aemQnu0-047|So when we think about it, you'd think, oh, maybe all solids float on their liquids.

oqN1aemQnu0-048|It's actually the reverse.

oqN1aemQnu0-049|Just because that's a common substance, water, and we see the solid floating on the liquid, we get the impression that that's common.

oqN1aemQnu0-050|It's actually the least common interaction.

oqN1aemQnu0-051|Most solids sink in their own liquid.

oqN1aemQnu0-055|So very near 0 Celsius, but a fraction of an atmosphere.

oqN1aemQnu0-056|There are 760 torr in one atmosphere.

OlehBTSyPDA-000|Let's do a calculation that's a titration calculation.

OlehBTSyPDA-002|The question is, what is the pH after those two are mixed?

OlehBTSyPDA-003|So I can think about this as a titration.

OlehBTSyPDA-005|The question is, how far along on the titration curve does this addition of strong base take me?

OlehBTSyPDA-006|Does it take me to the center of the buffer region?

OlehBTSyPDA-007|Is it enough to take me to the equivalence point?

OlehBTSyPDA-009|We have HAc plus water, forming acetic acid and H3O plus.

OlehBTSyPDA-010|That's one of the equilibria we have to deal with for this problem.

OlehBTSyPDA-011|But we want to find out, well, what are the initial conditions?

OlehBTSyPDA-012|How much HAc, how much Ac minus, and how much H3O plus are there at a point?

OlehBTSyPDA-013|And then we'll allow the equilibria to expand.

OlehBTSyPDA-014|And this is how you do equilibrium calculations.

OlehBTSyPDA-015|You find a point that you can nail down.

OlehBTSyPDA-016|Say, OK, these will be my starting conditions.

OlehBTSyPDA-017|And then you apply the equilibrium to see how it shifts from that one point.

OlehBTSyPDA-018|And that's the great thing about equilibria, they approach the same equilibria no matter where you start from.

OlehBTSyPDA-019|So as long as you can nail down one point that you know and then apply equilibrium from there, you're going to get to the correct equilibrium condition.

OlehBTSyPDA-023|Well, molarity times volume is the number of moles.

OlehBTSyPDA-024|So 0.01 moles of acetic acid.

OlehBTSyPDA-025|Now this is assuming no dissociation.

OlehBTSyPDA-026|That's fine.

OlehBTSyPDA-027|I can choose any point along my equilibrium to be my starting point.

OlehBTSyPDA-033|And I choose that because the weak acid reacts completely with the strong base.

OlehBTSyPDA-034|That's a very strong reaction to favor the products.

OlehBTSyPDA-038|So that's not really an equilibrium, that one just goes all the way towards products.

OlehBTSyPDA-039|So if we start there and say, what happens after that occurs?

OlehBTSyPDA-040|Are there an equilibrium in effect, that will calculate the pH of the solution.

OlehBTSyPDA-041|So let's do that.

OlehBTSyPDA-042|We'll say, these two will react completely.

OlehBTSyPDA-043|So every mole of base will react with a mole of acid.

OlehBTSyPDA-044|And I'll have-- this is essentially half of this.

OlehBTSyPDA-045|So half of my base-- excuse me.

OlehBTSyPDA-046|Half of my acid will react with this base, and I'll form 0.05 moles of the conjugate base.

OlehBTSyPDA-047|So the acid reacts with the base to form the conjugate base.

OlehBTSyPDA-049|Here, the acid reacting with the base to form the conjugate base.

OlehBTSyPDA-050|In this case, I've added half the number of moles of HA that I originally had.

OlehBTSyPDA-052|Half of these react, so I have equal concentrations essentially of this and this at this point in the titration.

OlehBTSyPDA-053|So equal concentrations of these two.

OlehBTSyPDA-054|Half of my acid has been converted into its conjugate base.

OlehBTSyPDA-055|My OH minus concentration, it's gone to zero.

OlehBTSyPDA-056|I've used up one for one.

OlehBTSyPDA-057|One of those react with one of those, producing one of these.

OlehBTSyPDA-058|So let's treat these now as the initial concentrations in an equilibrium calculation and see where that gets us.

OlehBTSyPDA-063|But I know they're both in about 100 millimeters.

OlehBTSyPDA-064|So I can convert these easily into concentrations, moles per liter.

OlehBTSyPDA-070|Now this initial point is quite a ways into our calculation, but it's just the first point where I'm going to allow the equilibria to occur.

OlehBTSyPDA-071|In all the previous steps, I've said they go to completion.

OlehBTSyPDA-072|So now I'm at a point where everything has gone 100%, and I'm going to let the equilibria start to take over.

OlehBTSyPDA-073|And I do that at this point.

OlehBTSyPDA-074|And I can do that for equilibria at any point.

OlehBTSyPDA-075|Choose a point, nail it down, say, this is where I'm going to start, and then let your equilibria table take over.

OlehBTSyPDA-076|So the change to get to equilibrium is a little of this.

OlehBTSyPDA-077|We'll dissociate.

OlehBTSyPDA-078|And actually at this point, I'm not even sure.

OlehBTSyPDA-079|I'm not sure if the equilibrium will go this way or this way.

OlehBTSyPDA-080|I'm just going to assume a little of this goes away.

OlehBTSyPDA-081|And if it does, it'll produce a little of this.

OlehBTSyPDA-082|Since there's equal amounts, who knows?

OlehBTSyPDA-083|Maybe it'll shift back this way.

OlehBTSyPDA-084|I suspect it'll go this way though, because I think HAc is a strong enough acid to dissociate a little bit more.

OlehBTSyPDA-085|That will produce a little H3O plus.

OlehBTSyPDA-086|And I'm saying initially there was none of this.

OlehBTSyPDA-093|So that's 10 to the minus 4.75.

OlehBTSyPDA-094|4.75 is the Ka for acetic acid.

OlehBTSyPDA-102|That is the H3O plus concentration.

OlehBTSyPDA-103|And notice that I left the k like this, because I knew after I get the H3O plus concentration, I'm going to take minus log of it anyway.

OlehBTSyPDA-104|So I'm going to go right back to the exponent.

OlehBTSyPDA-105|So if I calculate the pH, that's minus log of 10 to the minus 4.75, which is 4.75.

OlehBTSyPDA-106|So what I found is that the pH is numerically equal to the pKa.