In the classroom teaching of heat of combustion, we should first introduce combustion reaction and then lead to basic concept about it and about standard combustion reaction.

在燃烧热的课堂教学中，先介绍燃烧反应，再引出燃烧热、标准燃烧热的概念。

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Secondly, the enthalpy of elementary substance under standard state is defined as the criterion of component enthalpy, thus reaction heat is no longer needed in energy balance.

其次，热量衡算时，将标准状态下单质的焓定义为所有组分的基准焓，不再需要反应热数据。

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