迄今为止，我指的是价电子。

And by now, I mean the valence electrons.

youdao

我们还剩下多少个价电子？

How many valence electrons do we have left?

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我们需要考虑这些价电子。

We actually need to think about those valence electrons.

youdao

这是氟，同样的结构，只有氟有七个价电子。

Now here is fluorine, same skeleton, only fluorine has seven valence electrons.

youdao

好吧，氧具有最高价电子平均能。

All right, well, oxygen has the highest valence electron energy.

youdao

教授：5，有5个价电子，但原子序数是7。

PROFESSOR: five — there's five valence electrons, but the atomic number is actually seven.

youdao

价电子成键理论，非常容易理解。

So the idea behind valence bond theory is very easy to understand.

youdao

我想指出的是，核电子和价电子，之间的区别。

And I want to point out the difference between core electrons and valence electrons here.

youdao

我们的第二步，需要知道价电子的个数。

For our step two, what we need is number of valence electrons.

youdao

让我们用价电子成键理论来看一看甲烷。

So let's think about methane using valence bond theory.

youdao

例如，我们可以讨论氮原子，氮原子有5个价电子。

For example, we can talk about nitrogen, and nitrogen has five valence electrons shown here.

youdao

希望大家还记得，价电子与芯电子的定义。

So, hopefully, you remember what we mean by valence electrons versus core electrons.

youdao

它的平均价电子能很低。

It's got a very low average valence electron energy.

youdao

这是价电子，阳离子的电荷乘以，共同因子。

This is the valence, the charge on the cation times I will common factor this.

youdao

这是价电子，阳离子的电荷乘以，共同因子。

This is the valence, the charge on the cation times I will common factor this.

youdao