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Let's see what happens here, just the motif, one, two, three, four, three four, one two, and then the theme.
让我们看看到底发生了什么,正是动机,一,二,三,四,一遍又一遍,然后是主题
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OK. If last minus first is greater than or equal to 2-- sorry, less than 2, then either look at this thing or look at that thing.
大于等于儿，抱歉，是小于二,看看这里或者那里,这就是我说的要特别小心的地方。
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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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We all do believe something makes it true that two plus one equals three, but it's not the fact that empirical objects-- We don't do empirical experiments to see whether two plus one equals three.
我们都相信有些东西,使2加1等于3是正确的,但这不是说现实的东西,我们不会在现实中做实验,去看看二加一是不是等于三
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Often a good thing to start with is to put the lowest ionization energy atom in the middle, and if you don't have charge separation then go with that structure, but if you do find you have a lot of separation, such as the case in negative 2, positive 2, and minus 1, then you want to say wait a second, this is really bad in terms of formal charge, let me go ahead and see what other options I have here.
通常一开始把电离能最低的原子,放在中心位置就很好了，如果你发现电荷没有分开,那么这个结构就没问题了，但是如果你发现有很多分开的电荷，比如这种情况，有负二，正二和负一，那么你会想要说等一下，从形式电荷来看这很不好，让我去看看其它可能的选择。
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that's one way to think about it, and there's also another way, and this is the way that your book presents it. If you, in fact, have two of the same atom right next to each other, let's say you have a crystal, or let's say you're talking about a metal, what you can do is just look at the distance between the two nuclei, and split that in 1/2, and take the atomic radius that way.
这只是一种定义的思路，另外还有其它方法，也就是你们课本上的方法，如果你，事实上，有两个相同的原子彼此靠在一起，比如说你有一个晶体，或者说你讨论的是一个金属，你所要做的就是,看看这两个原子核之间的距离，然后将距离除以二，就得到了这个原子的半径。
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