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OK, so now we've got, taken an electron from that sulfur, put it here, an electron from that sulfur, put it here.
现在我们得到的是，从硫那儿得到一个电子，放在这儿，一来自于硫的电子，放在这儿。
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times 7, plus we have 6 in the sulfur, and oxygen is right above sulfur, so that also has 6.
二乘上七，加上硫的六个，而氧在硫的正上方，因此也有六个。
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2 3 Well, son of a gun, one, two, three, four, five, six, sulfur, We've got six. We've used all the electrons.
真见鬼，4，5，6，硫，共六个，我们已经用掉了所有的电子。
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The IgM is really five IgG-type molecules that are linked together through disulfide bonds, such that their FC portions are all pointing in and their antibody binding portions are all pointing out.
gM是由五个IgG分子组成的,IgG分子之间通过二硫键连接,免疫球蛋白尾部的FC片段都指向内侧,而抗体的抗原结合位点都指向外侧
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So why don't you tell me what the formal charge should be on the sulfur atom of thionyl chloride?
那么请大家来告诉我亚硫酰氯中,的硫原子应该有多少形式电荷？
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actually our third, but the second one we're going to talk about in terms of formal charge, which is thionyl chloride.
实际上是第三个，但它是第二个,形式电荷的例子，也就是亚硫酰氯。
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It could be aluminum, silicone, phosphorous, sulfur, c hlorine or argon.
答案可能是铝，硅，磷，硫,氯或者氩。
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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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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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We would expect the ionization energy to decrease, that means that sulfur has our lowest ionization energy.
我们预期电离能会降低，这就意味着硫的电离能最低。
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And what we have left here is the sulfur, which will also get a pair.
剩下的是硫，它也应该得到一对。
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So in one case, we could actually put carbon in the middle, in one place, we could put sulfur in the middle, and in one case we could put nitrogen.
那么有一种情况是，我们把碳放在中间，还有一种情况是，把硫放在中间，另外一种情况是把氮放在中间。
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But, the oxygen has taken two electrons from the sulfur.
但是，氧从硫那里得到了2个电子。
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So, if we compare the sulfur to the oxygen, the oxygen it turns out is more electronegative and that is what holds the negative charge in this molecule.
因此，如果我们来比一下硫和氧，氧应该有更高的电负性,而在这个分子中它确实有负的电荷。
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So, we can put our sulfur in the middle, and then it doesn't really matter how we draw the rest of it, where we put our c l's versus where we put our oxygen.
那么，我们可以把硫放在中间，然后把其它的原子画在哪里就不重要了，把两个氯原子与一个氧原子放在哪里都行。
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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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So if we look at sulfur, what we need to do is take the valence electrons in sulfur, and there are 6.
因此如果我们来看硫原子的话，我们需要做的是,将硫的价电子，有六个。
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So, for example, let's look at thiocyanate ion, we have c s and n.
比如，让我们来看一下硫氰酸根离子，我们有碳，硫和氮。
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And the last example that we're going to talk about is thionyl chloride, so it's s o c l 2. This is another good step forward, because now we actually have four different atoms in our molecule.
我们要讨论的最后一个例子,是氯化亚砜，就是硫，氧，氯，二，这又是一个进步，因为我们的分子中现在有四个不同的原子了。
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So I show that here, so in green, you have what's called a carboxcylic acid group, a c o o h, which gets converted by s o c l 2 to a c double bond o c l or an acid chloride.
我在这里用绿色表示，我们所说的羧酸族化合物，碳，氧，氧，氢，它被亚硫酰氯转化为,一个碳氧双键与碳氯单键组成的酰氯。
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So, in terms of ionization energy, we would expect to see sulfur in the middle.
因此，按照电离能，我们应该把硫放在中间。
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So, a lot of people I hear are saying sulfur, and that's right.
我听到很多人说的是硫，这是正确的。
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Well, this chlorine has taken one electron from the sulfur.
对了，这个氯从硫那里得到了一个电子。
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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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And what you find out if you do these calculations, is that you have a negative 1 for your formal charge on nitrogen, you have a negative 2 for your formal charge on carbon, and you have a positive 2 for your formal charge on sulfur.
而如果你做了这些计算会发现，氮的形式电荷量为负一，碳的形式电荷量为负二，而硫的形式电荷量为正二。
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I'll tell you a little about thionyl chloride as well.
关于亚硫酰氯，我也会给大家简单介绍一下。
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So, how many have we got in the sulfur?
在硫中有多少个呢？
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But in terms of drugs that don't look like maybe this compound was used in the synthesis, many of them might have used thionyl chloride, because it generates such a nice reactive intermediate that you can go on and make a bunch of different compounds from that intermediate.
但是对于药物来说,它们可能跟合成过程中用到的这种化合物并不相像，很多药物的制造过程中都会用到亚硫酰氯，因为它能产生活性如此之高的反应中间体,以至于你可以继续利用反应中间体,来制造一堆不同类型的化合物。
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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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So, if we look on the periodic table, comparing, for example, s to o, if we have s it's below o, what happens to ionization energy as we go down a table?
那么，如果我们看周期表上，比较，比如，硫和氧，硫在氧下面，当我们沿着表向下看的时候,电离能是怎么变化的？
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