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So, if we want to figure out the formal charge on the carbon, we need to take the number of valence electrons, so that's 4. We need to subtract the lone pair, what number is that? It's 2.
如果我们想算出碳原子的形式电荷，我们需要将价电子的个数，也就是四，减去孤对电子的个数，它是多少？是二。
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Thus isolated, thus removed, the vision acquired an especially keen charm that made me race with all speed toward my lone gratification.
如此形影相吊，如此销魂，这景色生出,一种勾人心魄的诱惑力，促使我全速跑向,我孤独的尤物。
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For the carbon, we start with 4 valence electrons, we have 0 lone pair electrons minus 4, and we end up with a formal charge of 0.
对于碳，我们从四个价电子开始，我们有零个孤对电子，再减去四，最终我们有零个形式电荷。
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If these bonds were all completely of equal distance apart, whether is was a lone pair or bonding electrons, 5° the angles would be 109 . 5 degrees.
如果不管它是孤对，还是成键，它们等距分开的话，键角是109。
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But because there's this lone pair here, it's pushing down on the other bonds, 5° so we end up with an angle of less than 109 . 5 degrees.
但因为这里有孤对，它会把其它键向下压，所以键角会小于109。
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So in oxygen we have a similar situation where, in fact, we are not going to promote any of the electrons because we have two lone pair electrons no matter what we do.
在氧中，情况很类似，我们不能激发电子,因为无论如何我们都有两个孤对电子。
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So in terms of nitrogen that starts off with a valence number of 5, again we have 2 lone pair electrons in the nitrogen, and again, we have 6 electrons that are shared.
对于氮来说,我们应该从五个价电子开始，同样，氮也有两个孤对电子，共用电子的个数也一样，是六个。
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Well, we're talking about a pretty high number here, so to make counting easier, we'll just say 10 lone pairs, because 20 lone pair electrons is the same thing as 10 lone pairs.
好吧，我们这里讨论的是一个挺大的数，为了数起来更容易，我们就说有十对孤对电子，因为二十个跟十对是一个意思。
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And it turns out that it's actually less than 109 . 5, because those lone pairs are pushing the bonds even further away.
所以结果是它要小于109。,因为孤对会把成键推向更远。
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For the sulfur, we start off with 6 valence electrons, minus 4 lone pair electrons, minus 2, taking in account our bonding electrons, so we end up with a formal charge of 0.
对于硫，我们从六个价电子开始，减去四个孤对电子，再减去二，算上我们的成键电子，因此最终我们有零个形式电荷。
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So since we have two lone pairs, we're going to be pushing down even further on the bonding electrons, so we're going to smoosh those bonds even closer together.
因为我们有了两个孤对，我们会把成键电子,更加向下压，所以我们把这些键更加紧得推到一起。
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So it looks a lot less messy if we just draw our Lewis structure like this for h c n, where we have h bonded to c triple bonded to n, and then a lone pair on the nitrogen there.
这看起来整洁了不少,如果我们把氰化氢的路易斯结构画成这样的话，这样我们就有氢与碳之间的单键和碳与氮之间三键，然后还有一对孤对电子在氮这里。
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And if we talk about chlorine, and both of the chlorines are the same in this case, we start with a valence number of 7 for chlorine, and then we subtract 6, because it had 6 lone pair electrons around each of the chlorine atoms.
而如果我们讨论氯的话，在这个例子中两个氯的情况都是一样的，从七个价电子开始，然后减去六，因为每个氯原子周围,都有六个孤对电子。
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So what we see is on ammonia here, 107 we know that it's less than a 109 . 5, it's actually 107, so it's less than a 109 . 5, because of that lone pair pushing down in the bonding electrons.
我们看到在氨分子里，我们知道它比１０９．５要小，它是，所以比109。5要小，因为孤对会把成键电子向下推。
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If we go to the oxygen atom, now we're talking about starting with 6 in terms of valence electrons again, but instead of 2, you can see we have 6 lone pair electrons around the oxygen minus 1/2 of 2, so we have minus 1 is our formal charge.
如果我们分析氧原子的话，现在我们讨论的还是,从六个价电子开始，但孤对电子不再是两个了，你会看到氧周围,有六个孤对电子，再减去二的一半，因此我们有一个负的形式电荷。
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If it were linear, which 32% of you seem have thought, that would have meant that our Lewis structure had no lone pairs in it, right, and that's not the case.
如果是直线，就像32%的同学认为的那样，这意味着Lewis结构里没有孤对,对吧，这是不可能的。
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We have two lone pairs, so if we thought about what the bonds were everywhere, 5° it would be 109 . 5, but it's bent because we're only looking at the bonds, we're not counting the Lewis structures in naming our geometry, but they do affect the angles.
我们有两个孤对，所以如果我们考虑它会成怎样的键时，应该成109。,但它是折线型，因为我们只考虑成键，在几何形状里不考虑Lewis结构，但它会影响角度。
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