So, the formula for enthalpy is usually written as change in enthalpy.

因此，焓的公式通常写成焓变。

It's analogous to the standard enthalpy of formation that we use to calculate change in enthalpy.

它类似于我们用来计算焓变的标准生成焓。

The law itself says nothing about the standard enthalpy of formation.

该定律本身并未提及标准生成焓。

Change in enthalpy is equal to the heat gained or lost by the system.

焓变等于系统获得或损失的热量。

Like enthalpy and entropy, we can't directly the free energy change of the whole reaction.

像焓和熵样， 我们不能直接表示整个反应的自由能变化。

So I guess in the capital H for enthalpy does kinda make sense.

所以我在大写的 H 中表示焓确实有点道理。

Why enthalpy change is different from heat, even though they turn out to be pretty much the same anyway.

为什么焓变与热不同， 尽管事实证明它们几乎是样的。

Like enthalpy or entropy, Gibbs free energy is a state function, so it can be calculated the same way.

与焓或熵样， 吉布斯自由能是个状态函数， 因此可以用相同的方式计算。

Well no, because you don't even know why enthalpy is so cool.

嗯，不，因为你甚至不知道为什么焓这么酷。

And we measure enthalpy with a weird little science called calorimetry.

我们用做量热法的奇怪小科学来测量焓。

Those bonds are nothing but energy, and using enthalpy, we can measure how much energy they have.

这些键只不过是能量， 使用焓，我们可以测量它们有多少能量。

These measurements are done at standard conditions, which we discussed in the enthalpy and entropy episodes.

这些测量是在标准条件下完成的， 我们在焓和熵情节中对此进行了讨论。

So, I wonder how that compares to the amount we would predict using Hess's Law and the standard enthalpy of formation?

所以，我知道这与我们使用赫斯定律和标准生成焓预测的量相比如何？

Hess' Law is often stated in terms of standard enthalpies of formation.

赫斯定律通常用标准生成焓来表述。

As long as you start with the same reactants and end with the same products, the enthalpy change is the same.

只要您从相同的反应物开始并以相同的产物结束， 焓变就相同。

Thanks to many hardworking chemists, the standard enthalpy of formation has been measured for hundreds of compounds.

感谢许多辛勤工作的化学家，已经测量了数百化物的标准生成焓。

And I'm very happy the inventors knew how to calculate the enthalpy change of chemical reactions.

我很高兴发明者知道如何计算化学反应的焓变。

Hopefully that sounds like fun because more about the ins and outs of this are coming in an episode on how to measure enthalpy.

希望这听起来很有趣，因为有关如何测量焓的集中将详细介绍这方面的来龙去脉。

A large change in enthalpy can determine the direction of a free energy change, even if the entropy changes in the opposite direction, and vice versa.

焓的大变化可以决定自由能变化的方向，即使熵的变化方向相反， 反之亦然。

Note that the standard enthalpy is in kilojoules while the standard entropy is in joules per Kelvin.

请注意，标准焓的单位是千焦耳， 而标准熵的单位是焦耳每开尔文。