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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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Yeah, so also 4. We started with 10 valence electrons, we used up 6 of those as bonding electrons, so we have 4 left, which will be lone pair electrons.
对，也是四个，我们从十个价电子开始，只用了六个来成键，因此我们还剩下四个，它们将成为孤对电子。
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Place the non-bonding pairs on peripheral atoms first, which the higher average valence electron energy.
首先将孤对电子放在外围的原子，那儿具有较高的平均价电子能。
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And we give different names, depending on what kind of electrons we're dealing with, so, for example, with h c l here, we can talk about having bonded versus lone pair electrons.
我们还起了不同的名字，给我们要处理的不同类型的电子，以氯化氢为例，我们来介绍一下成键电子与孤对电子。
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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 step seven is how many electrons do we have left over that are going to go into lone pairs? How many?
而第七步是我们剩下,多少电子成为孤对电子？多少？
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0. 26 minus 6, so that tells us 20, and these are all going to be lone pairs.
二十个，二十六减去六，因此是二十个，它们都会成为孤对电子。
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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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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, 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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So, lone pair electrons, actually, not lone pairs themselves.
注意是孤对电子，而不是电子对。
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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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or 1 lone pair, 2 lone pair electrons.
或者说一对孤对电子，两个孤对电子。
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And, how many non-bonding?
而孤对电子有多少呢？
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So we need to add those 2 valence electrons left as lone pair electrons in our structure.
因此我们需要将这两个剩下的价电子,作为孤对电子加到我们的结构中。
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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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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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So, which atom is in need of those lone pair electrons?
那么，哪个原子需要这对孤对电子呢？
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So how many lone pair electrons do we have?
那么我们有多少孤对电子呢？
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Lone pairs.
孤对电子。
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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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