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So, what will start with on Monday is doing the most simple example of methane using these Lewis structure rules.
因此，下周一上课,我们会先以最简单的例子--甲烷开始,使用这些路易斯结构的规则。
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All right. So let's think about how to draw the oh, actually, let me let you tell me how we should start this Lewis structure.
好，那么我们来想一想应该怎么画,噢，实际上，我想让大家来告诉我,我们应该怎么开始画这个路易斯结构。
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913 And, he didn't publish anything related to the Lewis structure until about 1912 or 1913.
直到1912或,他都没有出版任,何与路易斯结构式有关的东西。
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So in terms of remaining valence electrons we have 12, so we can finish off each of our Lewis structures, so that's our first structure there, and our second structure there.
那么关于剩下的价电子，我们有十二个，因此我们可以完成这两个路易斯结构了，那么这是我们的第一个结构，而那是我们的第二个结构。
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In terms of picking a Lewis structure that's going to be the lowest energy, what you want to do is put the atom with the lowest ionization energy in the center of your atom.
为了挑选一个具有,最低能量的路易斯结构，你需要把电离能最低的原子,放在最当中的位置。
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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, at the end of the class on Friday, we saw that list of eight steps that you always need to go through when you draw a Lewis structure.
在上周五的课的最后，我们看到了一张,包括八个步骤的流程表。
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All right. So, let's go ahead and draw our Lewis structure here with sulfur in the middle.
好，那么，让我们来把我们的,路易斯结构画在这，硫在中间。
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And in terms of thinking about it for organic chemistry or if you're interested in thinking about the mechanism maybe by which it is toxic, a first step would be to draw its Lewis structure.
而为了在有机化学中思考它,或者如果你对它,有毒的机理感兴趣的话，第一步要做的应该就是画出它的路易斯结构。
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And this structure that I've depicted here using the X's and O's is called the Lewis structure.
我在这儿描述的结构,用X和O表示电子的方式叫做Lewis电子式。
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So, which atom would you expect to be in the center of a Lewis structure for thionyl chloride?
那么，大家认为那个原子应该在,亚硫酰氯的路易斯结构的中心位置呢？
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But I want you to tell me in terms of thinking about formal charge, which Lewis structure would you predict to be the most stable?
但我想让大家告诉我,从形式电荷的角度考虑，你会预测哪一个路易斯结构是最稳定的？
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This is a good way to actually check if your Lewis structure is correct or not.
这是检验你的路易斯结构,是否正确的一个好方法。
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So this means we can actually calculate this for any molecule that we've drawn the Lewis structure for, because we actually do need to draw the Lewis structure before we know, for example, how many of each of these we have, or at least go through the rules.
这意味着我们可以将原来画过,路易斯结构的分子的形式电荷计算出来，因为我们其实在画出,路易斯结构之后才能知道，比如，这些量的值是多少，或者至少我们需要经过前面的那些步骤。
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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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the first step in any Lewis structure is drawing the skeletal structure.
画任何路易斯结构第一步,都是先画出它的骨架。
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So, let's quickly go through the Lewis structure for ozone.
那么，让我们很快地画出臭氧的路易斯结构。
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Lewis structure for N2 is one, two, three, four, five.
氮有五个电子，一二三四五。
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Well, first of all, let's look at the Lewis structure.
好，首先，我们看看它的路易斯结构。
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And resonance is the idea that sometimes one single Lewis structure does not adequately describe the electron configuration around a given molecule, so instead you need to draw two different Lewis structures to describe that more appropriately.
而所谓共振态,就是有时候一个路易斯结构不足以,完整描述一个给定分子的电子排布，因此这时你需要同时画出两个,不同的路易斯结构来描述它,这样会更恰当。
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What you'll actually find in terms of asking your TAs about the Lewis structure rules is that sometimes they won't be as good at them as you are, and the reason is once you've drawn enough of these structures, you start to get a lot of chemical intuition about it just looks wrong to you if it's wrong.
其实如果大家去问助教,路易斯结构的规则是什么的话,你会发现他们有时候可能并不比你们记得更清楚，因为一旦你画过足够多的路易斯结构，你就会开始获得很多化学直觉,如果它是错的，那么对你来说它看起来就是错的。
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So, in terms of finishing our Lewis structure, we're actually not done yet here, even though we have full octets, and we've used up all of our valence electrons, and the reason is because it's c n minus, so we need to make sure that that's reflected in our Lewis structure, so let's put it in brackets here, and put a minus 1.
那么，根据我们的路易斯结构的完成情况，我们实际上还没有全部完成，尽管我们有了填满的“八隅体“,而且用完了所有的价电子，原因就是因为这是一个负离子，我们需要确保我们的路易斯结构能反映出这一点，所以让我们给它加个括号，再加个负一。
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So it's really neat to think that your counterparts 100 years ago right here at MIT could have been sitting in a class where they had Lewis as their lecturer, and he's putting forth these ideas -- these are actually his lecture notes, even though it wasn't even published yet, and giving this idea of Lewis structure, which is exactly what we keep using today in order to make a lot of these predictions.
因此会有很棒的感觉，当想一想一百年以前像你们一样,在这上学的同学可能正坐在教室里,听路易斯讲课，而他正在提出这些想法-,-而这些正是他的课堂讲义，尽管当时还没有发表，但已经给出了路易斯结构的思想，这正是我们直到今天都一直在用的,用它来做很多预测。
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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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Right, it's called the Lewis structure.
它叫做Lewis电子式。
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So, if we use those two tips to try to figure out a structure, a skeletal structure, we would get this structure here if we write out the full Lewis structure.
那么，如果我们用这两个小窍门来,尝试写出它的结构，骨架结构，我们将会得到这样的结构,如果我们把完整的路易斯结构画出来的话。
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Step three in our Lewis structure rules is to figure out how many electrons we would need in order for every single atom in our molecule to have a full valence shell.
路易斯结构规则的第三步是,找出让分子中每个原子的价壳层,都排满应该需要多少个价电子。
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So, let's go ahead and draw our Lewis structure based on the rest of the rules now that we have a skeleton.
那么，让我们继续画我们的路易斯结构,看看在得到骨架之后还有哪些规则。
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So, our second step, as we go through our Lewis structure rules, is to figure out how many valence electrons we have in our entire molecule.
那么，我们的第二步，按照路易斯结构的规则，应该是判断在整个分子中,包含多少个价电子。
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All right, so this is the same procedure that we're going to go through, regardless of what kind of Lewis structure we're going to draw.
好的，这就是我们画路易斯结构,所需要完成的步骤，不管什么样的路易斯结构都要这样做。
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