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So we can have four total hydrogens bonding here, - and we can think about how to describe these carbon- carbon bonds.
我们这里一共有四个氢原子成键，我们可以考虑怎么来-,描述碳碳键。
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So in addition to having these two carbon bonds, we actually also have four carbon hydrogen bonds in addition to our carbon-carbon bonds.
在这碳碳之间的键以外，我们还有四个碳氢键,除了我们的碳碳键外。
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Well, if this bond has completely identically equal sharing of electrons, then this bond will be nonpolar.
如果一根键连的两个原子,对键上的电子吸引程度是完全等价的，那么这根键是非极性的。
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Now I could have made a key, keys don't have to be strings, but as it happened, I didn't.
现在我可以建立一个键了，键并不一定是字符串，但这儿既然已经是字符串了。
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So in a moment you're going to go ahead and hit the spacebar and then as things fall from the screen when they line up with the left arrow, hit the left arrow with a different arrow, hit that arrow and see how good a score you can get.
一会儿你走到前面，敲一下空格键,当屏幕上面的东西从左边往下掉的时候,你就敲一下键盘上的左键,是哪个方向，敲对应的方向键就可以了,我们来看看你能得多少分。
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And if we put that in our bond here, we have 1, 2, 3 bonds, plus we have one lone pair left over.
如果我们把它们放到键里，我们有1，2，3个键，还剩下一对孤对在这里。
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And so this lower level is called a bonding orbital, and it is a bonding molecular orbital.
所以能级较低的轨道叫做成键轨道，这就是成键分子轨道。
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It turns out that the antibonding orbital is a little bit higher from the atomic orbital level than the bonding orbital is lower.
这证明了,反键轨道,比原子轨道高,成键轨道比原子轨道第。
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So any time you have two atoms bonding, the bond axis is just the axis that they're bonding along.
任何时候如果你有两个原子成键，键轴就是它们成键的方向。
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So, we'll start today talking about the two kinds of molecular orbitals, we can talk about bonding or anti-bonding orbitals.
今天我们先来,讨论两种分子轨道，我们要讨论成键和反键轨道。
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And because of the way those antibonding orbitals are stacked, the two electrons go one each into those antibonding.
因为这样,反键轨道被堆积了，这两个电子都填到各自的反键轨道。
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All right, so the bonding order, you're correct, should be 2, if we subtract the number of bonding minus anti-bonding electrons and take that in 1/2.
好，你们是对的，键序为，如果我们用成键数,减去反键数除以2。
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so you can see that there is going to be two sets in antibonding, three sets in bonding for a net of one, giving us the single bond.
因此你能看到,反键轨道上有两组，三组成键，得到一组净成键，所以成的是单键。
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So you can see that this is non-bonding, this is even worse than non-bonding, it's anti-bonding, because we're actually getting rid of electron density between the two nuclei.
所以你可以看到这是不成键的，它甚至比不成键还糟糕，它是反键，因为我们实际上是去掉了,两个原子核之间的电子。
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And the other thing to point out is that the energy that an anti-bonding orbital is raised by, is the same amount as a bonding orbital is lowered by.
另外一个要指出的事情是,反键轨道引起的能量升高，和成键轨道引起的能量降低是相同的。
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So again, this is an anti-bonding orbital, and what you see is that there is now less electron density between the two nuclei than there was when you had non-bonding.
同样的，这是反键轨道，你们看到当你有反键轨道的时候,两个原子核中间的电子密度更小了。
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You might have thought before we started talking about molecular orbital theory that non-bonding was the opposite of bonding, it's not, anti-bonding is the opposite of bonding, and anti-bonding is not non-bonding.
你也许在我们讨论分子轨道之前,就想过非成键时成键的反面，它不是，反键才是成键的反面，反键不是非成键。
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So, when we think about a bond length, this is going to be the length of our bond here, that makes sense because it's going to want to be at that distance that minimizes the energy.
因此，当我们考虑一个键的长度的时候，这就应该是我们的键长，这是合理的,因为体系会在核间距达到这一距离时,能量到达最小值。
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Clearly, we put 2 for each bond, and now we end up having 2 remaining bonding electrons left.
显然，我们在每个键处放上两个电子，那么最后我们还剩下两个成键电子。
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Then minus 1/2 of 2, because we only have one bond or 2 electrons in a bond.
然后减去二的二分之一，因为我们只有一个键，一个键就是两个电子。
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So we know that it's 1, because we have 1, 2, 3, 4 bonding, minus 2 anti-bonding, and 1/2 of that is a bond order of 1.
我们知道它是，因为我们有1，2，3，4个成键，减去2个反键，它的一半就是键序为1。
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Because step five is that we need to fill in our bonding electrons, and we start it with filling in two electrons per bond.
因为第五步要做的是将我们的成键电子填在这，所以我们开始在每个键处填上两个电子。
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What you can do is you can iterate keys, which gives you the keys in the dictionary, and then you can choose them, but there's no guarantee in the order in which you get keys.
你能做的就是迭代得到键，这样就可以得到字典中，所有的键并进行选择，但是键的顺序,是没有保证的。
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So any time I draw these molecular orbitals, I do my best, and I'm not always perfect, yet trying to make this energy different exactly the same for the anti-bonding orbital being raised, versus the bonding orbital being lowered.
所以我在画这些分子轨道的时候，虽然不是很完美，但我总是尽量,让反键轨道引起的，能量升高和成键轨道。
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We see three bonding pairs so this is a triple bond, indeed a multiple bond.
我们看到3对成键电子所以这是一个三重键，它确实是多重键。
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The bond, it turns out, 5° is 104 . 5 degrees, that h o h bond.
这个键即，ＨＯＨ键角，是104。
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How many bonding electrons does c l have? All right. Let's see, we've got a mixed response here, it turns out it has two bonding electrons.
氯有多少成键电子？好，让我们来看看，大家的回答不太一致，结果应该是两个成键电子。
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So, this bond is going to be a little bit different than this bond.
所以这根键,与这根键略有些不同。
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I want to finish this discussion by including the anti-bonding orbital, and this is a tip for you when you're drawing your molecular orbital diagrams, any time you draw a bonding orbital, there is also an anti-bonding orbital that exists.
我想要以包含反键轨道,来结束这个讨论，告诉你们一个,画分子轨道图的小技巧，任何时候你画一个成键轨道，都会存在一个反键轨道。
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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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