And now we're almost done, except what we H really want is delta H and not delta U, right.
我们差不多已经完成了,除了我们实际上想要的是Δ
So this delta energy here is very simply the energy of the initial state minus the energy of the final state.
很简单的,这个能量差等于,初始能量减去末能量。
And if you work out the energetics as we've gone with thermochemistry, dH you discover there's a huge negative delta H.
如果你计算能量变化,就像在化学热力学中所作的一样,你会发现很大的负的。
8 You will see if you get --I think the delta here is 1.78, 8 which is roughly 1.8.
我认为电负性差值应该是1。,约等于1。
Chiefly what we hear about is in the area of the Nile Delta, right there on the Mediterranean Sea.
绝大部分都集中在,尼罗河三角洲地区,就在地中海入海口
They had moved the capital up to the Delta region.
他们已经将首都迁移至三角洲地区。
Some of you are sound asleep, deep in delta.
有些现在正蒙头大睡,就是δ波。
And typically, we'll be treating at least some cases where we're dealing with ideal gases in which case we can easily get delta u.
那么我们也可以定出功,对吧?,典型地,我们至少会处理,一些理想气体的情况。
And we saw that in fact in this case delta S of mixing, we calculated it, saw that it is positive.
实际上如果我们计算气体混合过程中,熵的变化,我们会发现这个量是正的。
And in physics, when physicists want to say "a little bit of," delta they write lower case delta.
在物理里,他们想要表示一点点这个概念时“,常在值前面写。
This is equal to zero. So this irreversible process this Joule-Thomson process, is a constant enthalpy process. Delta h for this process is equal to zero.
等于0。所以这个不可逆过程,也就是焦耳-汤姆逊过程,是一个等焓过程。
delta E What we do is ask ourselves what is the delta E?
我们做的是问问我们自己,什么是?
It turns out after you do all the math, H it turns out to be delta H equals zero.
要等你做完所有的计算之后,才能知道结果,结果证明Δ
That's the important message, delta H of formation of the products, minus delta H of formation of the reactants.
去反应物的生成焓,这,是个重要的信息,生成物的生成焓,减去反应物的生成焓。
PROFESSOR BAWENDI: So the question was, for an isothermal expansion, delta u does not change, therefore, The answer is that's true only for an ideal gas.
你的问题是,在等温过程中,内能是否,这只对理想气体成立。
For isothermal expansion, that means that delta u does not change, but delta q is equal to delta w?
在等温过程中,是不是内能不变,Δq等于Δw?
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