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And the reason that this should be so fast is we already did all the calculations for the formal charges.
这应该很快就能做出来的原因是,我们已经做完了关于形式电荷的所有计算。
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So, when we think about any type of formal charges, we have to assign these based on a formula here, which is very easy to follow.
那么，不管我们要考虑什么样的形式电荷，我们都必须依靠这个公式，它很容易理解。
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We could also figure out the formal charges, and obviously the formal charges between these two atoms, they're going to be identical, we're only dealing with oxygen atoms here.
我们还可以把形式电荷算出来，显然这两个原子的形式电荷，应该是完全相同的，我们要处理的只有氧这一种原子。
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And if we were to think about which one of these is better, it turns out that it's the same i in terms of formal charges, so that doesn't help us out.
而如果我们要考虑它们中的哪个更好，结果从形式电荷来看,它们之间没有区别，因此这不能帮我们进行判断。
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So we can do this for any final charge we have, if we have a molecule that has a charge of plus 2, then all of the formal charges should add up to plus 2 and so on.
对于任意净电荷的情况,我们都可以这样做，比如假设我们有一个带两个正电荷的分子，那么所有的形式电荷加起来应该等于正二，等等。
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So if we went through and drew out our Lewis structure following each of our steps, what we would get is this as our Lewis structure here, and we could figure out all of the formal charges.
那么如果我们按照流程,经过所有的步骤来画路易斯结构，我们会得到这样的路易斯结构，然后我们可以算出所有的形式电荷。
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So again, we should be able to check all of our formal charges and make sure they add up to 0, which they do, and that makes sense, because we have a neutral atom in terms of thionyl chloride.
因此同样地，我们可以检验一下,我们所有的形式电荷是否正确,确保它们加起来等于零，而它们确实是这样，这是合理的，因为亚硫酰氯是一个中性原子。
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And then we can go ahead and let's quickly write out w hat the formal charges for all of these will be.
然后我们可以开始很快地,把所有的形式电荷都写出来。
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So that means if we add up all of the formal charges within the molecule, what we would expect to see is that they sum up to give a net charge of negative 1.
那么这就意味着如果我们把这个分子中,所有的形式电荷加起来，我们应该会看到它们加起来,之后得到的净电荷量为负一。
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And what's important to keep in mind about formal charge is if we have a neutral atom, such as we did in thionyl chloride here, the sum of the individual formal charges on individual atoms within the molecule have to equal 0.
而关于形式电荷记住一点是很重要的,那就是如果我们有一个中性原子，比如亚硫酰氯，那么这个分子中的所有原子的,形式电荷之和应该等于零。
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Also, formal charges can be checked, as I just said.
另外，我们可以检验一下形式电荷是否正确，就像我刚才说的。
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If we look at our last structure here where we have nitrogen the middle, we can also figure out all those formal charges, and in this case we have plus 1 on the nitrogen, we have minus 2 on the carbon, and then we end up with a 0 on the sulfur there.
如果我们来看看最后一个结构,在中间的原子是氮，我们同样可以计算出所有的形式电荷，而在这种情况下，氮为正一，碳为负二，而最后硫为零。
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But we could, for example, look at a case where we have several different structures that look pretty good, and the one we want to determine as being the lowest energy structure is the one in which the absolute values of the formal charges are going to be lower, so essentially that they have less charge separation.
但是我们可能，比如，遇到一种情况,有好几个候选的路易斯结构看起来都挺好的，这时候我们就需要,通过比较哪个形式电荷的绝对值更低,来决定哪个结构的能量更低，本质上这个结构中分开的电荷更少。
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It's always a good first approximation, because you need to start somewhere in terms of drawing Lewis structures, but then if you go and figure out the formal charge and you just have lots of charge separation or very high charges, like a plus 2 and a minus 2 and a minus 1 all different places in the atom, what it should tell you is maybe there's a better structure.
它总是一个好的第一近似，因为在画路易斯结构的时候,你总需要一个起点，但是如果你在算出形式电荷之后,发现有很多电荷分开了,或者说有很高的电荷，比如有一个正二，一个负二，还有一个负一1,在原子的各个地方，这应该就是在告诉你,或许还有一个更好的路易斯结构。
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