The partial pressure of the water, of gaseous water above that equilibrium of ice and water is not one bar, it's much less.
哪里错了吗?,问题在于,冰水混合物上方的,大气中水蒸气的分压,不是一个大气压。
and crashed onto all of the stuff in the bedroom.
然后砸下来,压在卧室里所有的东西上。
It was highly elevated above all other priorities and absort the lion share of effort and attention of the White House.
是压在所有其他首要任务之上的,在白宫人力物力方面,都占了很大的比重。
Pulling this lever or pushing the button would actually rotate the paper enough so that you'd be on a new line and it would also move the little imprinting head that prints the letters of the alphabet and such all the way to the left.
拉杆或按下按钮会让纸翻一下,这样你就能在新的一行上打字了,同时移动打印字母的,压印头,这样也能移到最左边。
It is taking place inside this thing, and it's a constant pressure, and we'll do it reversibly, right. So that's what we've got.
它是绝热的,在这个内反应,是在恒压下,它是可逆的,对吧?
There was the wonder I felt when I saw a brace of mountain like, spotted, black-and-white horses clopping down a dusty road through clouds of powdered clay.
我觉到很美妙,当我望见一大群如山般高大的,黑白斑点马压过土路,我觉到很快乐。
If we want to know your blood pressure, you put on the cuff, you've got a measure.
如果想知道你的血压,把设备压在手腕处,就得到一个测量值
He presents himself, in other words, as a human being of unparalleled piety and devotion who will risk life itself rather than quit the post that has been given to him.
他呈现的自我,换句话说,是极度虔诚敬神的人类,甚至压下自己的生命作赌注,也不愿放弃这个天赐的角色。
Why didn't the guys in the middle get crushed?
为什么中间的几排人没给压扁呢
My son,when he was in Seconde, which is the first year of French high school, they were out blocking traffic until some angry driver rolled over the foot of a protestor and then everybody kind of went off and ate pizza.
我的儿子,他高一,也就是法国高中的第一年,他们堵住交通,直到一个愤怒的司机压过一个抗议者的脚,他们才散开回去吃披萨
And one of their behaviors is pressing the lever.
其中的一个动作便是压杠杆。
So, this path right here from this top red path is an isobaric process.
所以上面这条红色的路径,就是个等压过程。
OK, so this, what I've sketched here would be a constant pressure calorimeter. There's a reaction.
好,我画的就是一个恒压量热计,其中进行一个反应。
If you have an isobaric you're going to have to calculate where the energy changes, and that's a calculation that's likely on the homework and very like on an exam as well, too.
在等压过程中,我们需要计算能量的变化,我们在作业,和考试中,就会遇到这类问题。
so that's what we think we know in constant pressure calorimetry.
好,我想这就是我们,在恒压量热法中所知道的。
This depends on the path. It tells you right here the path is constant pressure. These don't depend on the path, right. V doesn't care how you v get there. u doesn't care how you get there.
这由变化的具体路径决定,这个小脚标表明过程是恒压的,这些量都与具体路径无关,即不管是通过什么路径使得体积变化为Δ
STUDENT: Just a quick question on some of the constraints, like isothermal, isobaric, isovolumetric expansion.
学生:我有个关于,等温,等压,等容等约束条件的小问题。
And our heat of reaction or enthalpy of reaction is defined as the enthalpy at constant pressure.
我们的反应热,或反映,的焓被定义为恒压,等温。
It's going to take place in there. It's going to be a constant pressure, it might be open to the air, or even if it isn't, there might be plenty of room, and it's a liquid anyway, so the pressure isn't going to change significantly.
也许它是液体,它在这个位置,这是恒压的,它也许是连通大气的,就算不是,它也有,足够的空间,而它是液体,压强不会显著地改变。
We already did that. OK, dH/dT constant pressure is Cp. That was easy one.
我们已经做过这个计算了,好的,在恒压,状态下的偏H偏T就是Cp,这个很简单。
Cp And delta T is given by the heat, which has to do with how much of the candle burnt, divided by the constant pressure heat capacity.
T等于热量q除以恒定的等压热容,其中热量与,蜡烛燃烧的多少相关。
Over here, we have dq=Cp dT, the heat, the proportionality between heat - and temperature rise is given by this, the constant pressure heat capacity.
这里我有dq=CpdT,这是热量,这是联系热量,和温度变化的系数,恒压热容。
dT That means that dH is also equal to dH/dT, constant pressure dT. All right, so now I've T ot more dH/dT under constant pressure.
也等于偏H偏T恒压乘以,现在我已经得到了在恒压,状态下的偏H偏。
We're not going to have the constant pressure heat capacity, we're going to have the constant volume heat capacity, right.
这里出现的,不是等压热容,而是等体热容。
It's constant pressure. OK, so now, last time you looked at the Joule expansion to teach you how to relate derivatives like du/dV.
这是恒压的,好,上节课你们,学习了焦耳定律,以及怎样进行导数间的变换。
You just change volume to pressure and basically you're looking at enthalpy under a constant -- anything that's done at a constant volume path with energy, there's the same thing happening under constant pressure path for enthalpy.
可以看到这就是把体积换成了压强,一般我们都是在一种恒定状态下,考虑焓的,任何在恒容条件下,能伴随能量变化的东西,也在恒压条件下伴随焓同样地变化,所以你可以经常。
Normally this is used for a reaction in the condensed phases and liquid usually.
通常它是用于凝聚态,液体相的反应,这是一个恒压量热计。
The constraint isn't constant temperature because the temperature is going to be changing.
是在不停变化的,不是恒压,因为我们已经有Δp了。
T Remember, we're trying to get delta H, p we're trying to get dH/dT constant pressure and dH/dp constant temperature. OK, these are the two things were trying to get here.
想要得到在恒压状态下的偏H偏,和在恒温状态下的偏H偏,好的,这是两个我们,在这里想要得到的东西。
应用推荐