ceaglex/VisualTTS_Chem · Datasets at Hugging Face

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k09wNUM2xkA-008\|So the entropy of those systems is zero.
k09wNUM2xkA-009\|Then we'll take and add all the entropies for warming them and changing the phase till we get to the standard state.
k09wNUM2xkA-025\|Notice as well, as you compare hydrogen and oxygen, oxygen has a larger standard molar entropy than hydrogen.
k09wNUM2xkA-026\|And that's because the heat capacity of oxygen is greater.
k09wNUM2xkA-027\|Remember, the heat capacity is involved in all these warming steps.
k09wNUM2xkA-028\|And oxygen has a higher heat capacity because oxygen-- some of the energy goes into tumbling the oxygen molecule.
k09wNUM2xkA-029\|And it requires more energy to tumble an oxygen, because of the heavier atoms, than a hydrogen.
k09wNUM2xkA-030\|So oxygen has a higher heat capacity.
k09wNUM2xkA-031\|Each joule of heat you add to oxygen goes into rotating that molecule.
k09wNUM2xkA-033\|Here are some compounds.
k09wNUM2xkA-036\|And we can calculate the entropy change for a chemical reaction using standard molar entropies.
t6cGw1scLvc-000\|Another way to do a process would be to seal it in a thermal container so heat can't flow.
t6cGw1scLvc-001\|When heat can't flow, we call those processes adiabatic.
t6cGw1scLvc-002\|For adiabatic compression and expansion, we can also talk about energy changes.
t6cGw1scLvc-006\|Now it can't absorb a joule of heat to replace the joule of work it did to re-energize itself.
t6cGw1scLvc-007\|So I do a joule of work, I use a joule of energy.
t6cGw1scLvc-008\|Do a joule of work, use a joule of energy.
t6cGw1scLvc-009\|My energy drops.
t6cGw1scLvc-010\|And for an ideal gas, if the energy drops, the temperature drops.
t6cGw1scLvc-011\|So ideal gas is expanding adiabatically, work is negative, and the change in energy, negative.
t6cGw1scLvc-012\|It can also be zero because I could expand against a vacuum and not have to do work.
t6cGw1scLvc-013\|What about compression?
t6cGw1scLvc-014\|If I compress the gas, now work is being done on the gas.
t6cGw1scLvc-015\|And the gas is saying I'm getting this energy from work, but I can't release it as heat, q has to be zero, so my energy just goes up.
t6cGw1scLvc-017\|Practically, it usually means you just do the process quickly because you can quickly do work, but heat flow always takes time.
t6cGw1scLvc-018\|So a rapid process is often an adiabatic process.
t6cGw1scLvc-019\|And we can expand either adiabatically, or we can be compressed adiabatically.
t6cGw1scLvc-020\|For ideal gases these are the summary.
3T5TXTUaA_E-000\|Let's look at a couple acids reacting with each other.
3T5TXTUaA_E-001\|So, here's acid HA1, just a generic acid, and HA2, generic acid.
3T5TXTUaA_E-002\|They have pKa's, where the pKa1 is less than pKa2.
3T5TXTUaA_E-010\|We're looking at two weak acids reacting together.
3T5TXTUaA_E-015\|So, HA1 is the stronger acid.
3T5TXTUaA_E-016\|So, if it's a HA1 versus HA2, which will have the higher concentration in solution?
3T5TXTUaA_E-017\|Well, HA1 is the stronger acid.
3T5TXTUaA_E-018\|It will dissociate more than HA2.
3T5TXTUaA_E-023\|I encourage you to do that.
3T5TXTUaA_E-024\|Write out the acid equilibrium expressions.
3T5TXTUaA_E-026\|HA1, stronger acid, forces this towards products.
3T5TXTUaA_E-027\|That's a K larger than 1.
WMAnyBjtj1Y-000\|In the laboratory, we need a relationship between the microscopic properties-- numbers of particles-- and the macroscopic properties-- the mass that we can measure.
WMAnyBjtj1Y-001\|And we find that using relative masses.
WMAnyBjtj1Y-003\|So 12 grams of carbon-12 has Avogadro's number, 6.02 times 10 to the 23rd particles of carbon-12.
WMAnyBjtj1Y-004\|Hydrogen is 1/12 as massive.
WMAnyBjtj1Y-005\|So one gram of hydrogen has 6.02 times 10 the 23rd particles-- a 12 to 1 ratio.
WMAnyBjtj1Y-009\|So if I wanted to react oxygen and hydrogen atoms in a 1 to 1 ratio, I should keep the mass ratio 16 to 1.
WMAnyBjtj1Y-010\|What if I wanted to react them in a 2 to 1 ratio-- two hydrogens for every oxygen to form, say, water?
WMAnyBjtj1Y-012\|I can do this with the molecules themselves.
WMAnyBjtj1Y-013\|In fact, I can add up the atomic relative masses to get the molecular relative masses.
WMAnyBjtj1Y-017\|Here's a couple of molecules.
WMAnyBjtj1Y-018\|H2O and CO2, water and carbon dioxide.
WMAnyBjtj1Y-019\|Water, relative mass 18.
WMAnyBjtj1Y-022\|So how do I know one is bent and one is linear, both three-atom molecules?
WMAnyBjtj1Y-023\|Well, that's the nature of the quantum mechanical interaction of the electrons that form the bonds in these molecules.
WMAnyBjtj1Y-024\|And we'll study that in detail in this course.
WMAnyBjtj1Y-028\|That's, say, about this much water in the liquid phase.
WMAnyBjtj1Y-029\|If it were in the gas phase, the volume would be about 1,000 times as large.
WMAnyBjtj1Y-030\|But here is 18 grams of water.
WMAnyBjtj1Y-031\|That's not very much-- one mole.
WMAnyBjtj1Y-032\|So let's look at 55-mole samples of some elements and molecules.
WMAnyBjtj1Y-033\|Here's water.
WMAnyBjtj1Y-034\|Now, water, 55 moles, is 55 times 18 grams of water.
WMAnyBjtj1Y-035\|But the cool thing is, here's 55 times 18 grams of water, but I know how many particles are there.
WMAnyBjtj1Y-036\|There's 55 times Avogadro's number, 55 times 6.02 times 10 to the 23rd particles, in here.
WMAnyBjtj1Y-037\|Now, I also have carbon.
WMAnyBjtj1Y-038\|Here's 55 moles of carbon.
WMAnyBjtj1Y-039\|And this has the same number of particles as water particles.
WMAnyBjtj1Y-040\|They're both 55 moles.
WMAnyBjtj1Y-041\|And their masses, actually, they're quite similar.
WMAnyBjtj1Y-042\|And we can look at the table and see that.
WMAnyBjtj1Y-043\|Water has relative mass 18, carbon, relative mass 12.
WMAnyBjtj1Y-044\|So those are very similar masses.
WMAnyBjtj1Y-045\|Now, I also have aluminum here.
WMAnyBjtj1Y-046\|Now, aluminum has mass about-- well, looks like twice carbon.
WMAnyBjtj1Y-047\|And, yeah, I feel that.
WMAnyBjtj1Y-048\|This is twice as massive, 55 moles of aluminum, about twice as massive as 55 moles of carbon.
WMAnyBjtj1Y-049\|I also have lead.
WMAnyBjtj1Y-050\|I can barely lift the 55 moles of lead.
WMAnyBjtj1Y-051\|Here's 55 moles of lead.
WMAnyBjtj1Y-052\|Very massive, because each lead atom is something like eight times the mass of the aluminum atoms.
WMAnyBjtj1Y-053\|So very much more massive, 55 moles of lead, than 55 moles of aluminum.
WMAnyBjtj1Y-054\|Both the same number of particles, but each lead particle is something like eight times heavier.
WMAnyBjtj1Y-055\|So that's a lot of mass.
WMAnyBjtj1Y-056\|Now, you may be curious.
WMAnyBjtj1Y-057\|Why are these numbers for my relative masses not exactly integers?
WMAnyBjtj1Y-058\|Well, that's because in nature every carbon, for instance, does not have a mass of 12.
WMAnyBjtj1Y-059\|There are some carbon atoms out there that have a mass of 13.
WMAnyBjtj1Y-060\|In fact, about 1% of all carbon atoms in nature have a mass of 13.
WMAnyBjtj1Y-064\|We call them isotopes.
WMAnyBjtj1Y-065\|So this is an average over all the isotopes of the various elements that have different masses.
Nb76my9vHLY-000\|Let's try to draw some Lewis electron dot structures.
Nb76my9vHLY-001\|Formaldehyde is a common compound, CH2O.
Nb76my9vHLY-002\|The question I have is, which of these structures is the correct Lewis electron dot structure for formaldehyde?
Nb76my9vHLY-009\|We're writing the Lewis electron dot structure for formaldehyde.
Nb76my9vHLY-010\|Whenever you write Lewis electron dot structures, you first have to get the correct number of electrons.
Nb76my9vHLY-011\|So you add up the valence electrons for all the participating atoms.
Nb76my9vHLY-012\|So we'll take carbon, which has four valence electrons.
Nb76my9vHLY-013\|We'll take an oxygen with six valence electrons.
Nb76my9vHLY-014\|And we need to hydrogens.
Nb76my9vHLY-015\|Each has one valence electron.

k09wNUM2xkA-008|So the entropy of those systems is zero.

k09wNUM2xkA-009|Then we'll take and add all the entropies for warming them and changing the phase till we get to the standard state.

k09wNUM2xkA-025|Notice as well, as you compare hydrogen and oxygen, oxygen has a larger standard molar entropy than hydrogen.

k09wNUM2xkA-026|And that's because the heat capacity of oxygen is greater.

k09wNUM2xkA-027|Remember, the heat capacity is involved in all these warming steps.

k09wNUM2xkA-028|And oxygen has a higher heat capacity because oxygen-- some of the energy goes into tumbling the oxygen molecule.

k09wNUM2xkA-029|And it requires more energy to tumble an oxygen, because of the heavier atoms, than a hydrogen.

k09wNUM2xkA-030|So oxygen has a higher heat capacity.

k09wNUM2xkA-031|Each joule of heat you add to oxygen goes into rotating that molecule.

k09wNUM2xkA-033|Here are some compounds.

k09wNUM2xkA-036|And we can calculate the entropy change for a chemical reaction using standard molar entropies.

t6cGw1scLvc-000|Another way to do a process would be to seal it in a thermal container so heat can't flow.

t6cGw1scLvc-001|When heat can't flow, we call those processes adiabatic.

t6cGw1scLvc-002|For adiabatic compression and expansion, we can also talk about energy changes.

t6cGw1scLvc-006|Now it can't absorb a joule of heat to replace the joule of work it did to re-energize itself.

t6cGw1scLvc-007|So I do a joule of work, I use a joule of energy.

t6cGw1scLvc-008|Do a joule of work, use a joule of energy.

t6cGw1scLvc-009|My energy drops.

t6cGw1scLvc-010|And for an ideal gas, if the energy drops, the temperature drops.

t6cGw1scLvc-011|So ideal gas is expanding adiabatically, work is negative, and the change in energy, negative.

t6cGw1scLvc-012|It can also be zero because I could expand against a vacuum and not have to do work.

t6cGw1scLvc-013|What about compression?

t6cGw1scLvc-014|If I compress the gas, now work is being done on the gas.

t6cGw1scLvc-015|And the gas is saying I'm getting this energy from work, but I can't release it as heat, q has to be zero, so my energy just goes up.

t6cGw1scLvc-017|Practically, it usually means you just do the process quickly because you can quickly do work, but heat flow always takes time.

t6cGw1scLvc-018|So a rapid process is often an adiabatic process.

t6cGw1scLvc-019|And we can expand either adiabatically, or we can be compressed adiabatically.

t6cGw1scLvc-020|For ideal gases these are the summary.

3T5TXTUaA_E-000|Let's look at a couple acids reacting with each other.

3T5TXTUaA_E-001|So, here's acid HA1, just a generic acid, and HA2, generic acid.

3T5TXTUaA_E-002|They have pKa's, where the pKa1 is less than pKa2.

3T5TXTUaA_E-010|We're looking at two weak acids reacting together.

3T5TXTUaA_E-015|So, HA1 is the stronger acid.

3T5TXTUaA_E-016|So, if it's a HA1 versus HA2, which will have the higher concentration in solution?

3T5TXTUaA_E-017|Well, HA1 is the stronger acid.

3T5TXTUaA_E-018|It will dissociate more than HA2.

3T5TXTUaA_E-023|I encourage you to do that.

3T5TXTUaA_E-024|Write out the acid equilibrium expressions.

3T5TXTUaA_E-026|HA1, stronger acid, forces this towards products.

3T5TXTUaA_E-027|That's a K larger than 1.

WMAnyBjtj1Y-000|In the laboratory, we need a relationship between the microscopic properties-- numbers of particles-- and the macroscopic properties-- the mass that we can measure.

WMAnyBjtj1Y-001|And we find that using relative masses.

WMAnyBjtj1Y-003|So 12 grams of carbon-12 has Avogadro's number, 6.02 times 10 to the 23rd particles of carbon-12.

WMAnyBjtj1Y-004|Hydrogen is 1/12 as massive.

WMAnyBjtj1Y-005|So one gram of hydrogen has 6.02 times 10 the 23rd particles-- a 12 to 1 ratio.

WMAnyBjtj1Y-009|So if I wanted to react oxygen and hydrogen atoms in a 1 to 1 ratio, I should keep the mass ratio 16 to 1.

WMAnyBjtj1Y-010|What if I wanted to react them in a 2 to 1 ratio-- two hydrogens for every oxygen to form, say, water?

WMAnyBjtj1Y-012|I can do this with the molecules themselves.

WMAnyBjtj1Y-013|In fact, I can add up the atomic relative masses to get the molecular relative masses.

WMAnyBjtj1Y-017|Here's a couple of molecules.

WMAnyBjtj1Y-018|H2O and CO2, water and carbon dioxide.

WMAnyBjtj1Y-019|Water, relative mass 18.

WMAnyBjtj1Y-022|So how do I know one is bent and one is linear, both three-atom molecules?

WMAnyBjtj1Y-023|Well, that's the nature of the quantum mechanical interaction of the electrons that form the bonds in these molecules.

WMAnyBjtj1Y-024|And we'll study that in detail in this course.

WMAnyBjtj1Y-028|That's, say, about this much water in the liquid phase.

WMAnyBjtj1Y-029|If it were in the gas phase, the volume would be about 1,000 times as large.

WMAnyBjtj1Y-030|But here is 18 grams of water.

WMAnyBjtj1Y-031|That's not very much-- one mole.

WMAnyBjtj1Y-032|So let's look at 55-mole samples of some elements and molecules.

WMAnyBjtj1Y-033|Here's water.

WMAnyBjtj1Y-034|Now, water, 55 moles, is 55 times 18 grams of water.

WMAnyBjtj1Y-035|But the cool thing is, here's 55 times 18 grams of water, but I know how many particles are there.

WMAnyBjtj1Y-036|There's 55 times Avogadro's number, 55 times 6.02 times 10 to the 23rd particles, in here.

WMAnyBjtj1Y-037|Now, I also have carbon.

WMAnyBjtj1Y-038|Here's 55 moles of carbon.

WMAnyBjtj1Y-039|And this has the same number of particles as water particles.

WMAnyBjtj1Y-040|They're both 55 moles.

WMAnyBjtj1Y-041|And their masses, actually, they're quite similar.

WMAnyBjtj1Y-042|And we can look at the table and see that.

WMAnyBjtj1Y-043|Water has relative mass 18, carbon, relative mass 12.

WMAnyBjtj1Y-044|So those are very similar masses.

WMAnyBjtj1Y-045|Now, I also have aluminum here.

WMAnyBjtj1Y-046|Now, aluminum has mass about-- well, looks like twice carbon.

WMAnyBjtj1Y-047|And, yeah, I feel that.

WMAnyBjtj1Y-048|This is twice as massive, 55 moles of aluminum, about twice as massive as 55 moles of carbon.

WMAnyBjtj1Y-049|I also have lead.

WMAnyBjtj1Y-050|I can barely lift the 55 moles of lead.

WMAnyBjtj1Y-051|Here's 55 moles of lead.

WMAnyBjtj1Y-052|Very massive, because each lead atom is something like eight times the mass of the aluminum atoms.

WMAnyBjtj1Y-053|So very much more massive, 55 moles of lead, than 55 moles of aluminum.

WMAnyBjtj1Y-054|Both the same number of particles, but each lead particle is something like eight times heavier.

WMAnyBjtj1Y-055|So that's a lot of mass.

WMAnyBjtj1Y-056|Now, you may be curious.

WMAnyBjtj1Y-057|Why are these numbers for my relative masses not exactly integers?

WMAnyBjtj1Y-058|Well, that's because in nature every carbon, for instance, does not have a mass of 12.

WMAnyBjtj1Y-059|There are some carbon atoms out there that have a mass of 13.

WMAnyBjtj1Y-060|In fact, about 1% of all carbon atoms in nature have a mass of 13.

WMAnyBjtj1Y-064|We call them isotopes.

WMAnyBjtj1Y-065|So this is an average over all the isotopes of the various elements that have different masses.

Nb76my9vHLY-000|Let's try to draw some Lewis electron dot structures.

Nb76my9vHLY-001|Formaldehyde is a common compound, CH2O.

Nb76my9vHLY-002|The question I have is, which of these structures is the correct Lewis electron dot structure for formaldehyde?

Nb76my9vHLY-009|We're writing the Lewis electron dot structure for formaldehyde.

Nb76my9vHLY-010|Whenever you write Lewis electron dot structures, you first have to get the correct number of electrons.

Nb76my9vHLY-011|So you add up the valence electrons for all the participating atoms.

Nb76my9vHLY-012|So we'll take carbon, which has four valence electrons.

Nb76my9vHLY-013|We'll take an oxygen with six valence electrons.

Nb76my9vHLY-014|And we need to hydrogens.

Nb76my9vHLY-015|Each has one valence electron.