Abstract: Gibbs free energy, a fundamental yet abstract concept in chemical engineering thermodynamics, serves as the pivotal criterion for determining the direction and extent of spontaneous processes under isothermal and isobaric conditions. To address students’ difficulties in comprehending the essence and applications of Gibbs free energy, this study proposes a four-tier teaching framework encompassing conceptual definition, criterion application, microscopic mechanisms, and engineering practice. The methodology integrates rigorous thermodynamic principles with intuitive understanding through standardized terminology, illustrative chemical engineering examples, visual diagrams, and relatable analogies. It elucidates the interplay between enthalpy and entropy changes, along with the quantitative relationship between Gibbs free energy and molecular dissociation constants. Furthermore, the study systematically examines the application of Gibbs free energy in core chemical engineering domains, including reaction engineering, separation processes, and pharmaceutical design. Teaching implementations at Sun Yat-Sen University’s Chemical Engineering program demonstrate that this approach significantly enhances students’ comprehension of abstract concepts and their ability to apply thermodynamic theories to solve practical engineering problems. This research provides valuable insights for optimizing the instruction of Gibbs free energy and other complex concepts in chemical engineering thermodynamics education.

Key words: Gibbs free energy, Chemical engineering thermodynamics, Spontaneous process, Enthalpy, Entropy, Phase equilibrium, Teaching optimization