as independent disciplines. However, the concepts and techniques dev- oped for these disciplines are extremely useful in many other disciplines. This book is intended to provide an introduction to these disciplines while revealing the connections between them. Chemical kinetics uses the statistics and probabilities developed for statistical thermodynamics to explain the evolution of a system to equilibrium. Irreversible thermodynamics, which is developed from the equations of classical thermodyn- ics, centers on distance- dependent forces, and time-dependent ?uxes. The force ?ux equations of irreversible thermodynamics lead are generated from the intensive and extensive variables of classical thermodynamics. These force ?ux equations lead, in turn, to transport equations such as Fick's ?rst law of diffusion and the Nernst Planck equation for electrochemical transport. The book illustrates the concepts using some simple examples.