热化学是化学热力学的一部分,它的主要任务是研究化学变化或物理过程中能量变化的规律。当物质的状态发生改变时,常常伴随着产生热效应,通过量热法可测定出这些热效应值,如燃烧热、熔化热、溶解热、混合热、比热、吸附热以及各种反应热等。这些热效应数据,在解决化学热力学问题时,可计算生成焓、生成自由能、熵等热力学函数,从而可以判别一个化学反应的方向和反应的限度。同时,在物质结构、生理学、地球化学等基础理论研究中,如探讨晶体结构、生物变化、矿物成因等,也有很重要的作用。此外,在热机、化工和其它工程设计中,也都是不可缺少的重要数据。因 Thermochemistry is a part of chemical thermodynamics. Its main task is to study the laws of energy changes in a chemical or physical process. When the state of the material changes, it is often accompanied by the generation of thermal effects. The calorific value can be determined by calorimetry, such as heat of combustion, heat of fusion, heat of dissolution, heat of mixing, specific heat, heat of adsorption and various reaction heats. These thermal effect data can solve the problem of chemical thermodynamics, calculate the enthalpy of formation, generate the thermodynamic functions such as free energy, entropy and so on, so as to determine the direction of a chemical reaction and the reaction limit. At the same time, it also plays an important role in the study of basic theories such as material structure, physiology and geochemistry, such as exploring the crystal structure, biological changes and mineral genesis. In addition, heat engine, chemical and other engineering design, are also indispensable important data. because