-
When we have an isolated system, the criterion that determineswhether something happens spontaneously is the entropy has to increase.
对于孤立系统,决定一个过程是否自发发生的判据为：,熵必须增加。
-
OK, clearly we'd be much better off if we had some systematic quantitative way to tell whether something would happen spontaneously.
好，如果我们有一些系统定量的方法来判断,一个过程是否会自发进行,那就会更好了。
-
And so what this gave us was a very, very useful general criterion for determining whether something happened spontaneously.
这个告诉我们的是一个,非常非常一般的判据,他能帮助我们判断一个过程是否自发进行。
-
That tells us the direction of spontaneous change for ordinary processes, chemical processes, mixing and you name it, under conditions that are easy to achieve in the lab.
这个物理量告诉我们在实验室,能够实现的条件下通常的过程，化学过程，混合以及你所能想到的过程，自发进行的方向。
-
So now, now that we've got all three of the major laws of thermodynamics, what I want to start in on is a discussion of what happens spontaneously.
现在既然我们已经得到了,热力学的三个主要定理，我想现在开始讨论的是,什么过程会自发进行。
-
We'll see that next time, and then we'll generalize in a broader sense to look at the direction in which spontaneous processes go. ?
我们下节课将讲述这方面的内容，然后会进一步推广到更广的意义上去,研究任何自发过程,的进行方向？
-
Anything else, which is to say any spontaneous process, it'll be less than zero.
其它任何情况下，也就是任何自发过程，都将小于零。
-
And this is for any spontaneous change.
这对于任何自发过程成立。
-
So now we have a different sign for delta H and it still happens spontaneously.
现在自由焓的变化的符号不一样了,但是这个过程仍然自发的进行。
-
And in fact any spontaneous process will make it go up.
事实上,任何自发过程都会导致熵上升。
-
Sort of direction of spontaneous change.
自发过程的方向。
-
And yet, these things are all spontaneous processes.
然而，这些过程都是自发进行的。
-
And so, we'll be able of follow that further and see really how to determine the direction of spontaneity for a whole set of processes,really in principle for any processes, went analyzed properly.
我们接下来，就进一步看看,怎么确定一个,任意自发物理,过程的方向，的整个过程。
-
And for the spontaneous change which happens irreversibly That means that'll be dq irreversible.
对于不可逆的自发过程,这说明dq是不可逆的,当过程是可逆时。
-
So this isn't the most useful form that we can have, but what we'll see shortly is that from this, we can then derive further criteria for essentially any set of variables or any set of external constraints, like constant temperature or pressure or volume and so forth that we might set.
所以这不是我们所能得到的最有用的形式，但是我们会很快看到，我们能够进一步推导出包含任意变量,或者任意约束的自发过程判断标准，比如说恒定的温度，压强,体积或者其他我们能够给出的约束。
-
if it's a reversible process then the equality holds, but if it's irreversible, which means it happens spontaneously, T then dS is greater than this.
对于可逆过程，等号成立，但是如果是不可逆过程，这些不可逆过程是自发进行的，那么dS大于dq除以。
应用推荐