因此我们看到氮的形式电荷是零。
So what we see is that the formal charge on the nitrogen is 0.
因此最终我们得到碳的形式电荷量是负一。
实际上我们还没学如何计算形式电荷，我们很快就会学到了。
We haven't actually learned how to calculate the formal charge yet, we'll learn it soon.
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？
So why don't you tell me what the formal charge should be on the sulfur atom of thionyl chloride?
好，让我们在讲形式电荷之前，再给一个例子画一下路易斯结构。
All right. So let's try one more example of drawing Lewis structures before we talk about formal charge.
那么我们现在做完了，实际上应该还有一步，那就是确定形式电荷。
So now we're done, actually there is one more step, which is to determine the formal charge.
而我们流程中的第八步，同样是，形式电荷，我们很快就会讨论它。
And our eighth step in the process, again, is formal charge, which we will talk about very soon.
希望我们下一次做关于形式电荷的问题的时候，大家能够做得快一点。
So hopefully next time we do a formal charge question, we'll get everyone back up to speed.
而它确实是这样，因此我们知道我们很有可能，算对了我们的形式电荷。
And it does, so we know that we're probably on target in terms of calculating our formal charge.
我们会在课程的后半部分讲到氧化数，但它和形式电荷完全不是同一个概念。
We'll get to oxidation number in the second half of this course, but it's not in any way the same idea as formal charge.
那么，在这种情况下，我们看到氮的形式电荷是负的，而在这种情况下，氧的是负的。
So, in this case, we see that our formal charge is negative on the nitrogen, in this case it's negative on oxygen.
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。
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，让我们来算一下已经,用过的一些例子的形式电荷，那么对于氰离子。
So, let's just figure this out for some of the examples we did, so for the cyanide anion.
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。
And the reason that this should be so fast is we already did all the calculations for the formal charges.
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？
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?
那么现在我们已经做了足够多的画路易斯结构的练习，让我们来讨论一下如何得出形式电荷。
So now that we have enough practice drawing Lewis structures let's talk about actually figuring out this formal charge.
我们之前做过的例题，都是非常简单直接的，因此我们还不需要，用形式电荷来做这种决定。
The examples we've done so far have been pretty straightforward, so we haven't needed to use formal charge to make this kind of decision.
说到形式电荷，基本上形式电荷就是，单个原子在形成分子之后，是得到了电子还是失去了电子的一种量度。
So when we talk about formal charge, basically formal charge is the measure of the extent to which an individual atom within your molecule has either gained or lost an electron.
我们还可能遇到另外一种情况，那就是在我们需要进行，选择的两种路易斯结构中，形式电荷具有相似的绝对值。
So, we can also get into a case where we have similar values in terms of absolute values of formal charge between two different molecules we're deciding between in their Lewis structures.
那么，这些就是在我们需要在,不同的路易斯结构之间做选择的时候,我们如何用形式电荷来进行判断的各种方法。
So, these are the different ways that we can actually go ahead and use formal charge when we're choosing between different types of Lewis structures.
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。
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.
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。
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.
比如，可能它的形式电荷为负一，因为在一定程度上它得到了这么多的共用电子密度，那么它现在就有了负的形式电荷。
So for example, that might have a formal charge of negative 1, because to some extent it has gained that much electron density that it now has a formal charge that's negative.
而为了检验任何一个结构是否有效，看它们是不是好的路易斯结构，我们要做的最后一件事就是检查形式电荷。
And the last thing we do for any of our structures to check them and figure out are these valid or not valid, are these good Lewis structures is to check the formal charge.
因此我们会专门讲一讲，如何来画路易斯结构，然后再讨论形式电荷与共振论，它们也属于路易斯结构的范畴。
So we'll talk specifically about drawing Lewis structures and then about formal charge and resonance, which are within Lewis structures.
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。
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。
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.
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。
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.
那么在我们的第一个结构中，我们发现氮的形式电荷量是五减去四4,再减去二，因为我们开始有五个价电子，因此它的形式电荷量是负一。
So in our first structure, we would find for the nitrogen we have a formal charge 5 minus 4 minus 2, because we're starting with 5 valence electrons, so that is a formal charge of minus 1.
基于凝相机理与热解实验，从分子层面和化学反应的角度，结合价键、形式电荷、链反应等理论和固体单元推进剂的燃烧状况，提出了AP与HMX间的“连锁互动”机制。
Related to bond polarity, formal charges on atoms, chain reaction theory and the comparison of solid monopropellant combustion and modeling, the "linkage mutualism"mechanism was proposed.
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