3.1 热化学和焓 Thermochemistry and enthalpy 3.2 熵和熵变—反应自发性的另一种 判据 Entropy and entropy change — judgment for spontaneous reaction 3.3 自由能——反应自发性的最终判 据 Free energy-the determined criterion for the spontaneous process 3.4 平衡状态和标准平衡常数 Equilibrium and standard equilibrium constant