The Frontier of Chemical Thermodynamics aims to provide adequate knowledge of various topics in a comprehensive manner, with a focus on making them easy to understand. This book provides a complete course in Thermodynamics for undergraduate, honours, and postgraduate students of Indian universities. It covers topics such as Fundamental Concepts, Behaviour of Gases, Zeroth Law of Thermodynamics, Work and Heat, First Law of Thermodynamics, Entropy and Second Law of Thermodynamics, Third Law of Thermodynamics, Thermochemistry, Free Energy Functions, Phase Rule, Solution Thermodynamics, Equilibrium Thermodynamics, Non-equilibrium Thermodynamics, and Statistical Thermodynamics. The objective of this book is to impart comprehensive knowledge of the subject to students and explain the concepts in simple language for easy understanding. The solutions to numerical problems are presented in a simplified form. Every effort has been made to make the book as error-free as possible. Constructive suggestions and feedback from readers will be gratefully acknowledged.