Abstract Boiling point under atmospheric pressure and saturated vapor pressure are commonly used to assess the ability of pure substances' volatilization. The reason why these two indicators can used to evaluate pure substances' volatilization is not clear and thermodynamic analysis is not completed. In this paper, thermodynamic analysis of pure liquid's volatilization was studied, and the thermodynamic model was established according to the second law of thermodynamics. Meanwhile, thermodynamic analysis of whether the molar enthalpy of vaporization at boiling temperature under atmospheric pressure act as a criterion for the volatilization of pure substances was carried out. The results show that the molar enthalpy of vaporization can be used as a new criterion for the volatilization of pure substances. The smaller the molar enthalpy of vaporization, the more easily the pure substances volatilize, and vice versa.
WANG Zheng, SHI Jia-Shun, KONG Hui, XIAO Sai-Jun. Thermodynamic Analysis of Pure Substances Volatilization[J]. Chinese Journal of Chemical Education, 2018, 39(10): 18-20.