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So if you think about any one of these carbon-carbon bonds, what type of a bond would you expect that to be?
如果你们考虑任何一个碳碳键，它是什么类型的？
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So in terms of thinking about ethane, we actually have two bond types that we're going to be describing just in terms of the carbon-carbon bond and then the carbon h bonds.
对于乙烷，我们有两种键,我们继续讨论一下,碳碳键,和碳氢键。
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As we see a little bit later, I could talk about the carbon-hydrogen bond in methane where there is a plurality of bonds. In this case, there is only the one bond but I just want to get the formulas.
因为我们后来看到一点点，我能讨论甲烷中的碳氢共价键,那有许多共价键，这种情况下，这只有一条共价键,但我想得到氟。
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And the last bond that we have here is a carbon-carbon bond, and this is our last p orbitals that are coming together.
最后一个键是碳碳键，这是最后一个组合的p轨道。
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This is very easy molecule because we know exactly where to put them without even having to think, we only have one option, and we'll make a triple bond between the carbon and the nitrogen.
这个分子非常简单,因为我们知道应该把它们放在哪里,甚至不用去想，我们只有一个选择，我们将在碳与氮之间形成一个三键。
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So let's take a look at what actually happens if we're talking about a carbon-carbon double bond, we're going to have a double bond.
让我们来看一看碳碳双键的情况,例如在乙烷里，我们有个双键。
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So why don't you tell me what the valence bond description would be of these carbon hydrogen bonds?
你们来告诉我,碳氢键的价,电子是怎样的？
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Our second bond is going to be between the carbon and the hydrogen atoms.
第二种键是,碳氢之间的键。
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So again, if we think about that shape of that carbon atom, it's going to be trigonal planar, 120° it's going to have bond angles of 120 degrees, because we have this set up of having three hybrid orbitals.
如果我们考虑碳原子的形状，它是平面三角形，键角是，因为我们有这三个杂化轨道。
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Now I want to ask, what's the nature of the carbon-hydrogen bond?
现在我想问问，碳氢键的本质是什么？
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If we think about bringing in those last two carbons, what you can see is that for every carbon, two of its hybrid orbitals are being used to bond to other carbons.
如果我们考虑引入最后两个碳原子，你会看到的是对于每个碳原子，其中的两个杂化轨道,和另外的碳原子成键。
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Let's look at this carbon-hydrogen bond.
我们来看看这跟碳氢键。
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sigma2sp It's going to be a sigma bond. So, we have sigma 2 s p, carbon 2 s p. So they're two s p bonds combining.
是sigma键，我们有，碳2sp。，所以它们是两个sp键结合。
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So it's along the bond axis and it's between a carbon s p 2 hybrid, and then the hydrogen is just a 1 s orbital that we're combining here.
所以它是沿着键轴方向的,而且这里是一个碳sp2杂化轨道，和一个氢的1s轨道的结合,在这里我们可以合并他们。
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This bond is polar, but again, as I alluded to earlier, because the carbon is centered in the tetrahedron, because of the sp3 hybridization, the molecule itself is symmetric and nonpolar.
这个键是非极性的，但是，我们断言过早，因为C是中心原子，由于sp3杂化，这个分子本身是非极性的且对称的。
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If we have, coming along this z axis, another carbon atom, we can actually form one bond between the two carbon atoms there.
如果我们在z方向，有另外一个碳原子，我们可以在,两个碳原子之间形成一个键。
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So for b 2, which is a single bond, that's 289 kilojoules per mole to break it, and it takes us more energy to break this double bond for carbon, which is 599 kilojoules per mole.
对于B2，它是单键，需要289千焦每摩尔来打破它，而对于碳双键,打破它要更多的能量，等于599千焦每摩尔。
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So in terms of the carbon hydrogen bond, it's a sigma bond, - because we define it -- any time we are bonding to an atom, we have to keep redefining our bond axis to whatever two atoms we're talking about.
对于碳氢键，它是sigma键，因为我们定义它-,任何时候我们有原子成键，我们要重新定义键轴方向,为我们所讨论的两个原子方向。
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So that's two of our types of bonds in benzene, and we have one type left, that's going to actually be the double bond or the pi bond that So we can have one bond here between this carbon's p orbital and this carbon's p orbital.
这就是苯环里的两种键，我们还剩一种，那就是这些p轨道之间，形成的双键或者π键,我们可以在这个碳的p轨道,和这个碳的p轨道之间有个键。
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