So if we have a negative change in energy for any reaction as it's written, what that actually means is we're giving off energy as the reaction proceeds.

如果我们像这里写的这样,在任何一个反应过后，得，到的能量变化为负值,这就意味着我们在这个过程中放出了能量。

麻省理工公开课 - 化学原理课程节选

Hess' Law states that for any chemical reaction, the energy change is path independent.

盖斯定律表明，对于任意化学反应，能量变化并非是路径依赖的。

麻省理工公开课 - 固态化学导论课程节选

Energy may be favoring reaction in one direction, toward let's say products that have lower energy.

能量上的变化可能支持反应，向着产物具有更低能量的方向进行。

麻省理工公开课 - 热力学与动力学课程节选

This means in order to do that we actually have to put 7 kilojoules per mole of energy into the reaction to make it happen.

这意味为了完成上面的反应,我们不得不往里面注入,7，千焦每摩尔的能量。

麻省理工公开课 - 化学原理课程节选

That is to say I can now reroute that sodium plus chlorine reaction and go a different way, but I still end up with the same change in energy.

也就是说，我可以重新定义一种,钠与氯的反应途径,从另一种途径来实现反应，但是能量的变化过程相同。

麻省理工公开课 - 固态化学导论课程节选

And the change in energy for this reaction is negative 349 kilojoules per mole.

然后得到这个过程的能量变化为,负的，349，千焦每摩尔。

麻省理工公开课 - 化学原理课程节选

this happens spontaneously, you actually get energy out of the reaction as this happens.

这是自发的，当反应发生的时候,你会自发地放出能量。

麻省理工公开课 - 化学原理课程节选

So, we were talking, however, about energy in terms of electron affinity, so we can actually relate electron affinity to any reaction by saying if we have this reaction written as here where we're gaining an electron, we say that electron affinity is just equal to the negative of that change in energy.

但是，我们现在讨论的能量,是电子亲和能，因，此我们可以将电子亲和能,与任何反应联系起来,只要我们将反应写成这种得到电子的形式，我们说电子亲和能就等于,反应前后能量变化的负值。

麻省理工公开课 - 化学原理课程节选