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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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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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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 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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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 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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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 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, 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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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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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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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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