A SIMPLE MEMORY METHOD FOR THE FUNDAMENTAL FORMULAS OF THERMODYNAMICS

We introduce a simple and practical method to be able to write down almost all the fundamental formulas of thermodynamics. Firstly, we write out in a certain order the four characteristic functions, internal energy U, free energy F, enthalpy H, and Gibbs function G, and the four basic thermodynamic variables, volume V, pressure P, temperature T, and entropy S. Secondly, some rules are specified. According to these rules, the intrinsic independent variables of each characteristic function are clearly revealed; the relationships between the characteristic functions, the partial derivatives of the functions with respect to the intrinsic variables, and the partial derivative relationships between the thermodynamic variables, i.e., Maxwell relations, can be put down. Finally, the pressure and volume are expanded to other intensive and extensive quantities. These rules of memory are actually a summary of the features of the basic formulas of thermodynamics.