An overview of prediction methods for thermophysical properties in chemical engineering is presented. As thermophysical properties, molar enthalpy, enthalpy of vaporization, and thermal conductivity are selected. The author categorized the prediction methods into three categories shown as follows:
I. Method based on principle of physical chemistry,
II. Method based on group contribution of molecular structure,
III. Method based on corresponding state principle.
Almost all the prediction methods are empirical modifications of the theory of physical chemistry. Empirical extension of theory can often lead to a method useful for prediction purposes. Prediction of enthalpy of vaporization from vapor pressure has been examined by using Antoine constants determined by the author for toluene with satisfactory results. Thermal conductivity of toluene is important, since toluene is standard substance for thermal conductivity observation. One of the latest group contribution method by Müller and Arlt (2014)²⁰⁾ is adopted for the prdiction of thermal conductivity of toluene. It is useful prediction method which can predict gas as well as liquid thermal conductivity. The result of prediction is satisfactory with error of -7.18%.