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You calculate how much heat is released in the reaction. And then what's going to matter is what's the heat capacity of the whole, of the calorimeter?
就是计算在反应中,放出了多少热量,接下来关键的是,整个量热计的热容是多少？
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What I really want to do is just give an example of what happens when you throw the thing, the material into a calorimeter and see how much the temperature changes.
我想做的是给出当,你把这些东西，这些材料扔进，量热计时会发生什么,看看温度会变化多少。
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Well what you do is you bomb the food and you use something called the bomb calorimeter that looks like this, and so essentially what you do is you put the food in this device that sits inside water.
我们要做的是燃烧食物,使用一种叫弹式量热器的工具,像这样,把食物放入这种仪器中,仪器会浸入水里
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I didn't even need to know that heat capacity of the product, right. Because it's effect the thermal mass of the product is negligible compared to the thermal mass of the calorimeter.
我甚至不需要知道生成物的,热容是多少，因为生成物的,热质量的作用相比于,量热计的热质量是可以忽略的。
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I mean the calorimeter is a big thing filled the little oil or whatever is inside it, right?
装满了油或别的什么东西,对吧？
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So we don't really need to put in a certain amount of heat and change the temperature of the products and the calorimeter and so on.
所以我们实际上并不需要输入,一定的热量，改变生成物,和量热计的温度之类。
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That'll be inside our calorimeter. It's insulated, and there's still a thermometer, so we can measure the temperature.
被放置在量热计里面，它是绝热的，同样有一个温度计，让我们可以测量温度。
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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。
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So this is a constant pressure calorimeter.
它做了很好的隔热处理。
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So delta u of reaction is approximately equal T to negative Cv for the calorimeter times delta T.
所以反应的ΔU近似等于,负的量热计的Cv乘以Δ
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Could be done, but easier is to just do the whole thing at constant volume, right, and just run the reaction that way and redo the calculation to be a constant volume rather than constant pressure calorimeter, right.
可以进行测量,但是如果在体积恒定的条件下,做这些会容易得多,还是这样进行反应,但是在等体而不是恒压条件下重新计算。
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Calorimeter doesn't change in this process.
量热计在这个过程中并没有改变。
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Same with the calorimeter, OK.
量热计也是一样。
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Fewer products and calorimeter at T1, right.
以及T1下的生成物和量热计，对吧？
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And that generally is just given by the heat capacity the calorimeter times delta T, right.. Because the heat capacity of the calorimeter just like this thing is not strongly temperature dependent, OK.
一般它就由量热计的热容,乘以ΔT给出，因为，量热计的热容,就像这张桌子一样,并不强烈依赖于温度。
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I've got reactants and calorimeter at T1.
我有T1下的反应物和量热计。
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