In this work, we present a little explored alternative for the study and classification of thermodynamic variables. Some methods in the theory of ordinary differential equations not only support the use and calculation of these variables but also assists the physicochemical interpretation. We explore the Euler's criterion as a resource to study and differentiate the state functions and process variables useful in chemical thermodynamics. For this purpose, we carry out the development of the differentials and their analysis in a simple, rigorous, and progressive way, in accordance with the level of the topics treated in graduate courses of physical chemistry and classical thermodynamics.
Keywords:
Euler's criterion; state functions; process variables; thermodynamics