The aim of this book is to develop the concepts and relations pertinent to the solution of many thermodynamic problems encountered in multi-phase, multi-component systems. In doing so, it emphasizes a comprehension and development of general expressions for solving such problems, rather than ready-made equations for particular applications. Throughout the book, the methods of Gibbs are used with emphasis on the chemical potential. Many topics omitted in more elementary texts are amply discussed defining the state of a thermodynamic system, particularly the indifferent systems; the use of the Gibbs-Duhem equation in single-phase and multi-phase component systems; the conditions of stability for single-phase and multi-phase component systems; and the graphical representation of the thermodynamic functions. Special attention is given to reference and standard states. The material is presented in a rigorous and mathematical manner, and SI units are used throughout. A detailed bibliography is also included. Thermodynamics of Chemical Systems is intended for all those concerned with the application of thermodynamics to chemical systems, including biochemists, metallurgists, physicists, and materials scientists as well as chemists. Research workers and graduate students in these areas will find this work to be a valuable textbook and reference book.