Of course, they're all sorts of conditions under which a reaction could be wrong in the lab or outdoors or however, right. But this is the way we're going to define delta H of reaction.

当然，在实验室或室外,之类的环境中，在这些条件下,反应可能出错，但这是我们,要定义反应的△H的方法。

麻省理工公开课 - 热力学与动力学课程节选