Air temperature and vapor pressure deficit were the key factors affecting transpiration.
气温和蒸气压不足是影响蒸腾作用的关键因素。
The pressure will result in the formation of a vapor pocket.
压力将导致形成一个蒸汽口袋。
So, that means that the vapor pressure above the solution is lowered. So I should have said vapor pressure lowering.
这就表示溶液上的，蒸汽压下降，所以这就是刚才说的饱和蒸汽压下降。
You expect the vapor pressure to go down.
可以预计蒸汽压会下降。
And a good guess is that that vapor pressure here, it's pretty close to the pressure that you would guess by using this diagram with the pure water. But the key word is, it's pretty close.
对吗？一个比较好的猜想就是，这里的蒸汽压非常接近那个大气压,我们利用纯水的相图计算得到的,关键是，非常接近。
That the vapor pressure of the solute is related to the mole fraction in the solution.
溶质的蒸汽压，和溶液中溶质的摩尔分数成正比。
We know there's vapor pressure there, right?
我们知道这里有蒸汽压？
Then I want to ask the question, what is the vapor pressure of the water?
现在我想问的是，水的蒸汽压是多少？
Obviously there's going to be a little bit of vapor pressure, even at room temperature.
很显然肯定,会有蒸汽压存在，即使是在室温下。
The pressure, the vapor pressure, of the water is going to be lower when the sugar is there.
当存在糖的情况下，水的蒸汽压会下降。
That means that the act of putting some solute in my water decreases the vapor pressure of the water in the gas phase Pretty simple. It's called vapor pressure law.
结果意味着在水中放入溶质的效果，是降低了气态水的蒸汽压，很简单，这叫做蒸汽压定律。
And we also drew a phase diagram to show how this vapor pressure lowering was going to imply freezing point depression and boiling point depression.
我们来画相图，蒸汽压下降，意味着凝固点降低，和沸点降低。
So when I have a pure water solution, the total pressure is going to be the same as the vapor pressure of water at a particular temperature Let's take temperature fixed at some value.
当溶液是纯水时，总压强应该等于纯水，在特定温度下的蒸汽压，我们让温度固定。
Meaning that the Henry's law constant is greater than the vapor pressure of the pure CS2.
意味着亨利定律常数，比纯cs2的蒸汽压大。
It's going to come from the vapor pressure lowering not from the osmotic pressure, which we'll do next.
我们可以从蒸汽压得变化，而不是渗透压，得到这个结果。
In other words, the vapor pressure over pure liquid a is higher than the vapor pressure over pure liquid B.
换句话说，液体A上的蒸汽压，比液体B上的蒸汽压大。
But the water is, vapor pressure is, very slow, very small.
但是水的蒸汽压很小。
So pure A. And pA is the vapor pressure of the mixture Which in this case here is the total pressure, because I don't have anything else that's volatile.
即纯净的A物质，pA是混合物得蒸汽压，在这里是总压强，因为我们没有加入任何不易挥发的溶质。
Which is the vapor pressure of the pure material times the, and the composition of the liquid phase, Raoult's law.
这个常数是纯物质的蒸汽压，乘以液相的组分，Raoult定律。
195torr The vapor pressure is 25.195 torr at 27 degrees C.
在27摄氏度时，蒸汽压为25。
Where you measure the pressure, the vapor pressure, as a function of temperature.
在实验中你可以测量蒸汽压，作为温度的函数。
And then the vapor pressure of both substances above gets lowered. Anybody want to guess why they got lowered?
两种物质的蒸汽压都会下降，有人猜一猜为什么二者的蒸汽压都会下降吗？
It's the usual, it's pretty close to the usual vapor pressure.
这很正常，水的蒸汽压非常接近通常的蒸汽压。
There's hardly any vapor pressure above your ice water glass.
冰水混合物上方,水蒸气的气压非常小。
You want to find the vapor pressure.
你需要找出蒸汽压。
Once the cold water enters the flack, the vapor pressure falls quickly.
一旦冷水进入长颈瓶，水气压就迅速下降。
There is vapor pressure lowering.
蒸汽压的下降。
Colligative properties are the properties like the vapor pressure, lowering when you have a mixture in a liquid, instead of having a pure substance you have amixture of substances here.
依数现象是这样一种现象,当你把物质混合在一起的时候,你不会得到纯物质,而是得到混合物质。
And we found that the gas-liquid coexistence point, the vapor pressure of the water, was less than if it were pure.
我们发现在汽液共存点，糖水中水的蒸汽压，小于纯水的蒸汽压。
And water vapor pressure is lower when the air is cooler, meaning sweat evaporates faster.
凉快时水蒸发压低，这意味着汗水能很快蒸发。
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