So notice a difference in these structures, is this has an n h bond whereas this has an o h bond.

注意它们之间的有一点不同，那就是一个有氮氢键,而另一个有氧氢键。

麻省理工公开课 - 化学原理课程节选

So, why don't you go ahead and tell me, keeping that in mind, which atom in terms of h c or n would you expect to be in the center of hydrogen cyanide?

那么，请大家来告诉我，并且记住它，你认为氢，碳和氮中哪个原子,应该在氰化氢的中间呢？

麻省理工公开课 - 化学原理课程节选

So between b e, and b, between n and o, magnesium and aluminum, and then phosphorous and sulfur, what we see here is that we're kind of going down, or quite specifically, we are going down.

比如从铍到硼，从氮到氧，从镁到铝，从磷到硫，我们在这些地方看到有点下降，或者可以明确地说，我们确实在下降。

麻省理工公开课 - 化学原理课程节选

So, for example, down here I wrote that it was n 2 and that it was h 2, but when I re-wrote the molecules up here, you saw that it's an h h single bond where it's a nitrogen-nitrogen triple bond.

比如，在这下面我写的是氮分子2,而这个是氢分子，但我在上面把这些分子的形式改写了，大家可以看到,这是一个氢与氢之间的单键，含一个氮与氮之间的三键。

麻省理工公开课 - 化学原理课程节选

So, the first thing we do is put two electrons between h and c, and then two electrons between c and n.

那么，我们先在氢和碳之间放两个电子，然后在碳和氮之间再放两个电子。

麻省理工公开课 - 化学原理课程节选

So, that also tells us that the n minus ion is less stable than the neutral atom itself.

而且，这还告诉我们,负一价的氮离子不如中性氮原子稳定。

麻省理工公开课 - 化学原理课程节选

So our skeleton tells us that carbon is in the middle, so we'll put the h on one side, and the n on the other side there.

我们的骨架告诉我们碳原子应该放在中间，因此我们把氢原子放在一边，把氮原子放在另外一边。

麻省理工公开课 - 化学原理课程节选

So, if we took the case of nitrogen, if we add an electron to nitrogen and go to n minus, we find that the change in energy is 7 kilojoules per mole.

如果我们以氮为例，如果我们给氮增加个电子令它变成-1价的氮，我们会发现能量的变化是，7，千焦每摩尔。

麻省理工公开课 - 化学原理课程节选

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。

麻省理工公开课 - 化学原理课程节选

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。

麻省理工公开课 - 化学原理课程节选

So, let's, for example, look at nitrogen. So n 2, we can do the chart here in green, so it's the green dotted line, and what we see is that we have now defined this energy as where the 2 nitrogen atoms are separated.

那么，让我们举个例子，看一下氮，那么氮分子，我们可以把它用绿色曲线画在这，这是绿色的虚线，可以看到,我们已经定义为零点能，当两个氮原子分离时。

麻省理工公开课 - 化学原理课程节选

So we have h c n.

那么我们有氢，碳和氮。

麻省理工公开课 - 化学原理课程节选