ceaglex/VisualTTS_Chem · Datasets at Hugging Face

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gAWuFYOUPSg-022\|So the outer 4p sees like one positive charge.
gAWuFYOUPSg-023\|So the effective charge on all of them is about one.
gAWuFYOUPSg-024\|For hydrogen, it's exactly one.
gAWuFYOUPSg-025\|And we can calculate these ionization energies.
gAWuFYOUPSg-026\|Hydrogen in the 2p state, its ionization energy still a quarter of a Rydberg.
gAWuFYOUPSg-027\|Helium in the 3p state, effective nuclear charge about 1, gives you about a ninth of a Rydberg.
gAWuFYOUPSg-028\|And then lithium in the 4p state, effective nuclear charge about one, gives you 1/16 of a Rydberg.
D8JCG-Opfwk-001\|The way you do that is you follow this recipe.
D8JCG-Opfwk-002\|You take the electrons, and you share them equally about each atom.
D8JCG-Opfwk-004\|And the difference will be formal charge.
D8JCG-Opfwk-005\|So let's do that.
D8JCG-Opfwk-006\|Nitrogen, in this case, has 1, 2, 3, 4 electrons in a bond.
D8JCG-Opfwk-008\|What about the oxygens?
D8JCG-Opfwk-011\|And it has to share these two with nitrogen, so one more.
D8JCG-Opfwk-012\|6 and 1 is 7.
D8JCG-Opfwk-013\|So seven electrons around oxygen in this molecule.
D8JCG-Opfwk-016\|It has the same number of electrons in the molecule and the neutral atoms.
D8JCG-Opfwk-017\|And it'll be minus one for this oxygen.
D8JCG-Opfwk-018\|It has one more electron in the molecule than it does in the neutral atom.
D8JCG-Opfwk-019\|Formal charge of zero and minus one will help us determine the quality of Lewis electron dot structures.
D8JCG-Opfwk-020\|And we'll look at that next.
fOVAF8nTATI-000\|Let's look at the ionization of some diatomic molecules.
fOVAF8nTATI-001\|I have H2 the molecule, He2 the molecule, and Li2 the molecule.
fOVAF8nTATI-011\|We're talking about the bond order of several ions.
fOVAF8nTATI-012\|So I'm going to ionize H2, He2, and Li2, and see what the bond strength is.
fOVAF8nTATI-013\|We'll coordinate the bond strength with the bond order.
fOVAF8nTATI-014\|So here are the molecular orbital diagrams for H2, He2, and Li2 with the appropriate electrons.
fOVAF8nTATI-017\|So 1, 2 bonding electrons minus 0 divided by 2 gives me 1.
fOVAF8nTATI-024\|The highest energy electron is a sigma bonding electron from H2.
fOVAF8nTATI-025\|And you already can imagine, if I'm removing a bonding electron, that can't make the bond more stable.
fOVAF8nTATI-026\|In fact, removing an electron leaves one electron in the sigma bonding orbital.
fOVAF8nTATI-027\|So if I calculate the bond order here, it's 1 minus 0 divided by 2.
fOVAF8nTATI-028\|The bond order has gone down to 1/2.
fOVAF8nTATI-029\|Here for helium, when I ionize, I remove an antibonding electron.
fOVAF8nTATI-032\|So the bond orders go to 1/2.
fOVAF8nTATI-033\|But the one that became more stable was helium.
fOVAF8nTATI-034\|Unstable as He2 the molecule, but as He2+ the ion has a higher bond order.
fOVAF8nTATI-035\|So in this case, the answer is He2, more stable upon ionization.
Q62PPzLln8E-000\|Let's look at that helium ion in a little more detail.
Q62PPzLln8E-001\|The helium plus ion, which transition has a wavelength that's equal to the 2-1 transition in the hydrogen atom?
Q62PPzLln8E-002\|So we're going to line up transitions between helium plus and hydrogen, which transition in helium is the same as 2-1 in hydrogen?
Q62PPzLln8E-011\|We're comparing hydrogen atoms to helium plus ions, both one electron systems.
Q62PPzLln8E-016\|The n equal 2 and n equal one, n equal 4 and n equal 2 energy levels line up.
qm1SjMuodYI-000\|Let's describe the bonding and the shape in SeF4.
qm1SjMuodYI-001\|In order to do that, you need to start with a good Lewis electron dot structure.
qm1SjMuodYI-002\|So you have to be very good at drawing your Lewis electron dot structure.
qm1SjMuodYI-003\|Here's SeF4.
qm1SjMuodYI-005\|And what we really need is the steric number around selenium.
qm1SjMuodYI-006\|So that steric number is 1, 2, 3, 4, 5.
qm1SjMuodYI-007\|I have to accommodate four fluorines and a lone pair for steric number five.
qm1SjMuodYI-008\|Once I have these steric number, I can get to the geometry.
qm1SjMuodYI-009\|It also gives me the hybridization.
qm1SjMuodYI-010\|So steric number five means I'm going to use five equivalent hybrid orbitals.
qm1SjMuodYI-014\|So our trigonal bipyramidal arrangement, but in this case, when we go to the molecular shape, we ignore electron pairs.
qm1SjMuodYI-015\|So we always name our shapes without the electron pair.
qm1SjMuodYI-016\|So removing that electron pair gives me a shape that looks like this, a little seesaw.
qm1SjMuodYI-017\|So there's an electron pair here, but the molecular shape is named just by the atoms.
pB0yR5kXQjI-000\|Let's look at some examples of molecular shapes.
pB0yR5kXQjI-001\|We'll start with the VSEPR, the Valence Shell Electron Pair Repulsion of the groups around a central atom.
pB0yR5kXQjI-002\|We'll count up the number of lone pairs and the number of bonded atoms around a central atom to determine the overall shape.
pB0yR5kXQjI-003\|Let's look at some examples.
pB0yR5kXQjI-004\|Here's carbon dioxide.
pB0yR5kXQjI-005\|Carbon dioxide has steric number 2.
pB0yR5kXQjI-006\|And I determine that from the Lewis dot structure.
pB0yR5kXQjI-007\|Now it's absolutely critical to get the Lewis dot structure correct, because that will tell you where the lone pairs and where the bonded atoms are, and it'll determine the steric number.
pB0yR5kXQjI-008\|Here, I've drawn the 16 electron system of carbon dioxide.
pB0yR5kXQjI-009\|Haven't drawn the full Lewis electron dot structure, there's electrons, as you know, around these oxygens, but it's the central atom administered in here.
pB0yR5kXQjI-013\|How do I fit two things as far away from each other as possible?
pB0yR5kXQjI-014\|180 degrees.
pB0yR5kXQjI-015\|Another example, boron dichloride with a positive charge.
pB0yR5kXQjI-016\|Three things-- steric number 2 around the central atom, linear arrangement.
pB0yR5kXQjI-017\|What about three things?
pB0yR5kXQjI-022\|The carbons in ethylene each have steric number 3.
pB0yR5kXQjI-023\|This carbon has to accommodate one, two, three things.
pB0yR5kXQjI-024\|This carbon also accommodates one, two, three things.
pB0yR5kXQjI-025\|All the bond angles in this molecule are 120 degrees.
pB0yR5kXQjI-026\|Interestingly, this molecule is also planar.
pB0yR5kXQjI-027\|All the atoms lie in one plane with bond angles of 120 degrees.
pB0yR5kXQjI-028\|We can keep going.
pB0yR5kXQjI-030\|Steric number 4, if you recall, is a tetrahedral arrangement.
pB0yR5kXQjI-031\|Not a square planar, but a tetrahedral arrangement in space.
pB0yR5kXQjI-032\|Tetrahedral angle is 109.5.
pB0yR5kXQjI-033\|That's how to put four things as far away from each other in space.
pB0yR5kXQjI-034\|So ammonia, the nitrogen has steric number 4, this ammonium ion with 1, 2, 3, 4 hydrogens around it.
pB0yR5kXQjI-035\|The oxygen in water, steric number 4-- 1, 2 hydrogens, and 1, 2 lone pairs.
pB0yR5kXQjI-036\|Now, steric number 4 for both of these, but ammonia we call a tetrahedral molecule.
pB0yR5kXQjI-037\|Water, we actually don't call tetrahedral, we just call it a bent molecule.
pB0yR5kXQjI-038\|The reason is, we only talk about the atomic centers when we're naming the shape of the molecule.
pB0yR5kXQjI-039\|This molecule is bent, these lone pairs don't factor in to our structure of the molecule.
pB0yR5kXQjI-040\|They influence it, but when we name this structure, we just call that bent, referring only to the atoms.
pB0yR5kXQjI-041\|Now this bent molecule, this bond angle is actually a little less than the 109.5 of true tetrahedral.
pB0yR5kXQjI-043\|In fact, this bond angle is closer to 105 degrees.
pB0yR5kXQjI-044\|104.5 is usually the bond angle reported for water.
pB0yR5kXQjI-045\|We can go to steric number 5.
pB0yR5kXQjI-047\|Two different positions-- the axial positions-- 180 degrees from each other-- and equatorial positions-- 120 degrees from each other.
pB0yR5kXQjI-049\|Phosphorus has steric number 5 in PCl5, it's a trigonal bipyramidal molecule.
pB0yR5kXQjI-050\|That's quite a mouthful, but you can practice saying that-- trigonal bipyramidal.
pB0yR5kXQjI-052\|In this case, two of the things are lone pairs.
pB0yR5kXQjI-054\|Knowing electron pairs, that molecule looks T-shaped.
pB0yR5kXQjI-056\|Now, it's interesting, you might say, well why didn't I take those two lone pairs and put them in the axial positions rather than the equatorial positions?

gAWuFYOUPSg-022|So the outer 4p sees like one positive charge.

gAWuFYOUPSg-023|So the effective charge on all of them is about one.

gAWuFYOUPSg-024|For hydrogen, it's exactly one.

gAWuFYOUPSg-025|And we can calculate these ionization energies.

gAWuFYOUPSg-026|Hydrogen in the 2p state, its ionization energy still a quarter of a Rydberg.

gAWuFYOUPSg-027|Helium in the 3p state, effective nuclear charge about 1, gives you about a ninth of a Rydberg.

gAWuFYOUPSg-028|And then lithium in the 4p state, effective nuclear charge about one, gives you 1/16 of a Rydberg.

D8JCG-Opfwk-001|The way you do that is you follow this recipe.

D8JCG-Opfwk-002|You take the electrons, and you share them equally about each atom.

D8JCG-Opfwk-004|And the difference will be formal charge.

D8JCG-Opfwk-005|So let's do that.

D8JCG-Opfwk-006|Nitrogen, in this case, has 1, 2, 3, 4 electrons in a bond.

D8JCG-Opfwk-008|What about the oxygens?

D8JCG-Opfwk-011|And it has to share these two with nitrogen, so one more.

D8JCG-Opfwk-012|6 and 1 is 7.

D8JCG-Opfwk-013|So seven electrons around oxygen in this molecule.

D8JCG-Opfwk-016|It has the same number of electrons in the molecule and the neutral atoms.

D8JCG-Opfwk-017|And it'll be minus one for this oxygen.

D8JCG-Opfwk-018|It has one more electron in the molecule than it does in the neutral atom.

D8JCG-Opfwk-019|Formal charge of zero and minus one will help us determine the quality of Lewis electron dot structures.

D8JCG-Opfwk-020|And we'll look at that next.

fOVAF8nTATI-000|Let's look at the ionization of some diatomic molecules.

fOVAF8nTATI-001|I have H2 the molecule, He2 the molecule, and Li2 the molecule.

fOVAF8nTATI-011|We're talking about the bond order of several ions.

fOVAF8nTATI-012|So I'm going to ionize H2, He2, and Li2, and see what the bond strength is.

fOVAF8nTATI-013|We'll coordinate the bond strength with the bond order.

fOVAF8nTATI-014|So here are the molecular orbital diagrams for H2, He2, and Li2 with the appropriate electrons.

fOVAF8nTATI-017|So 1, 2 bonding electrons minus 0 divided by 2 gives me 1.

fOVAF8nTATI-024|The highest energy electron is a sigma bonding electron from H2.

fOVAF8nTATI-025|And you already can imagine, if I'm removing a bonding electron, that can't make the bond more stable.

fOVAF8nTATI-026|In fact, removing an electron leaves one electron in the sigma bonding orbital.

fOVAF8nTATI-027|So if I calculate the bond order here, it's 1 minus 0 divided by 2.

fOVAF8nTATI-028|The bond order has gone down to 1/2.

fOVAF8nTATI-029|Here for helium, when I ionize, I remove an antibonding electron.

fOVAF8nTATI-032|So the bond orders go to 1/2.

fOVAF8nTATI-033|But the one that became more stable was helium.

fOVAF8nTATI-034|Unstable as He2 the molecule, but as He2+ the ion has a higher bond order.

fOVAF8nTATI-035|So in this case, the answer is He2, more stable upon ionization.

Q62PPzLln8E-000|Let's look at that helium ion in a little more detail.

Q62PPzLln8E-001|The helium plus ion, which transition has a wavelength that's equal to the 2-1 transition in the hydrogen atom?

Q62PPzLln8E-002|So we're going to line up transitions between helium plus and hydrogen, which transition in helium is the same as 2-1 in hydrogen?

Q62PPzLln8E-011|We're comparing hydrogen atoms to helium plus ions, both one electron systems.

Q62PPzLln8E-016|The n equal 2 and n equal one, n equal 4 and n equal 2 energy levels line up.

qm1SjMuodYI-000|Let's describe the bonding and the shape in SeF4.

qm1SjMuodYI-001|In order to do that, you need to start with a good Lewis electron dot structure.

qm1SjMuodYI-002|So you have to be very good at drawing your Lewis electron dot structure.

qm1SjMuodYI-003|Here's SeF4.

qm1SjMuodYI-005|And what we really need is the steric number around selenium.

qm1SjMuodYI-006|So that steric number is 1, 2, 3, 4, 5.

qm1SjMuodYI-007|I have to accommodate four fluorines and a lone pair for steric number five.

qm1SjMuodYI-008|Once I have these steric number, I can get to the geometry.

qm1SjMuodYI-009|It also gives me the hybridization.

qm1SjMuodYI-010|So steric number five means I'm going to use five equivalent hybrid orbitals.

qm1SjMuodYI-014|So our trigonal bipyramidal arrangement, but in this case, when we go to the molecular shape, we ignore electron pairs.

qm1SjMuodYI-015|So we always name our shapes without the electron pair.

qm1SjMuodYI-016|So removing that electron pair gives me a shape that looks like this, a little seesaw.

qm1SjMuodYI-017|So there's an electron pair here, but the molecular shape is named just by the atoms.

pB0yR5kXQjI-000|Let's look at some examples of molecular shapes.

pB0yR5kXQjI-001|We'll start with the VSEPR, the Valence Shell Electron Pair Repulsion of the groups around a central atom.

pB0yR5kXQjI-002|We'll count up the number of lone pairs and the number of bonded atoms around a central atom to determine the overall shape.

pB0yR5kXQjI-003|Let's look at some examples.

pB0yR5kXQjI-004|Here's carbon dioxide.

pB0yR5kXQjI-005|Carbon dioxide has steric number 2.

pB0yR5kXQjI-006|And I determine that from the Lewis dot structure.

pB0yR5kXQjI-007|Now it's absolutely critical to get the Lewis dot structure correct, because that will tell you where the lone pairs and where the bonded atoms are, and it'll determine the steric number.

pB0yR5kXQjI-008|Here, I've drawn the 16 electron system of carbon dioxide.

pB0yR5kXQjI-009|Haven't drawn the full Lewis electron dot structure, there's electrons, as you know, around these oxygens, but it's the central atom administered in here.

pB0yR5kXQjI-013|How do I fit two things as far away from each other as possible?

pB0yR5kXQjI-014|180 degrees.

pB0yR5kXQjI-015|Another example, boron dichloride with a positive charge.

pB0yR5kXQjI-016|Three things-- steric number 2 around the central atom, linear arrangement.

pB0yR5kXQjI-017|What about three things?

pB0yR5kXQjI-022|The carbons in ethylene each have steric number 3.

pB0yR5kXQjI-023|This carbon has to accommodate one, two, three things.

pB0yR5kXQjI-024|This carbon also accommodates one, two, three things.

pB0yR5kXQjI-025|All the bond angles in this molecule are 120 degrees.

pB0yR5kXQjI-026|Interestingly, this molecule is also planar.

pB0yR5kXQjI-027|All the atoms lie in one plane with bond angles of 120 degrees.

pB0yR5kXQjI-028|We can keep going.

pB0yR5kXQjI-030|Steric number 4, if you recall, is a tetrahedral arrangement.

pB0yR5kXQjI-031|Not a square planar, but a tetrahedral arrangement in space.

pB0yR5kXQjI-032|Tetrahedral angle is 109.5.

pB0yR5kXQjI-033|That's how to put four things as far away from each other in space.

pB0yR5kXQjI-034|So ammonia, the nitrogen has steric number 4, this ammonium ion with 1, 2, 3, 4 hydrogens around it.

pB0yR5kXQjI-035|The oxygen in water, steric number 4-- 1, 2 hydrogens, and 1, 2 lone pairs.

pB0yR5kXQjI-036|Now, steric number 4 for both of these, but ammonia we call a tetrahedral molecule.

pB0yR5kXQjI-037|Water, we actually don't call tetrahedral, we just call it a bent molecule.

pB0yR5kXQjI-038|The reason is, we only talk about the atomic centers when we're naming the shape of the molecule.

pB0yR5kXQjI-039|This molecule is bent, these lone pairs don't factor in to our structure of the molecule.

pB0yR5kXQjI-040|They influence it, but when we name this structure, we just call that bent, referring only to the atoms.

pB0yR5kXQjI-041|Now this bent molecule, this bond angle is actually a little less than the 109.5 of true tetrahedral.

pB0yR5kXQjI-043|In fact, this bond angle is closer to 105 degrees.

pB0yR5kXQjI-044|104.5 is usually the bond angle reported for water.

pB0yR5kXQjI-045|We can go to steric number 5.

pB0yR5kXQjI-047|Two different positions-- the axial positions-- 180 degrees from each other-- and equatorial positions-- 120 degrees from each other.

pB0yR5kXQjI-049|Phosphorus has steric number 5 in PCl5, it's a trigonal bipyramidal molecule.

pB0yR5kXQjI-050|That's quite a mouthful, but you can practice saying that-- trigonal bipyramidal.

pB0yR5kXQjI-052|In this case, two of the things are lone pairs.

pB0yR5kXQjI-054|Knowing electron pairs, that molecule looks T-shaped.

pB0yR5kXQjI-056|Now, it's interesting, you might say, well why didn't I take those two lone pairs and put them in the axial positions rather than the equatorial positions?