用双平衡法,研究了Cd(Ⅱ)-NH3-Cl--H2O体系中Cd(Ⅱ)配合平衡热力学,求出了氨水浓度和氯离子浓度在0～5 mol/L变化时,体系中各物种的平衡浓度,绘制了热力学平衡图,并对热力学计算结果进行了试验验证和差异分析。结果表明:镉离子浓度理论计算值与试验值之间的绝对平均误差为12.04%,说明该热力学模型是正确的,所选数据的准确性较好。 The equilibrium thermodynamics of Cd (Ⅱ) -NH3-Cl - H2O in Cd (Ⅱ) -NH3-Cl - H2O system was studied by the double equilibrium method. When ammonia concentration and chloride ion concentration were varied from 0 to 5 mol / L, The equilibrium concentration of species was calculated and the thermodynamic equilibrium diagram was drawn. The thermodynamic calculation results were verified by experiments and the differences were analyzed. The results show that the absolute mean error between theoretical calculated value and experimental value of cadmium ion concentration is 12.04%, indicating that the thermodynamic model is correct and the accuracy of the selected data is good.