This book is designed to serve as a textbook for core courses offered to postgraduate students enrolled in chemistry. This book can also be used as a core or supplementary text for nuclear chemistry courses offered to students of chemical engineering. The book covers various topics of nuclear chemistry like Shell model, fission/fusion reaction, natural radioactive equilibrium series, nuclear reactions carried by various types of accelerators. In addition, it describes the law of decay of radioactivity, type of decay, and interaction of radiation with matter. It explains the difference between ionization counter, scintillation counter and solid state detector. This book also consists of end-of-book problems to help readers aid self-learning. The detailed coverage and pedagogical tools make this an ideal textbook for postgraduate students and researchers enrolled in various chemistry and engineering courses. This book will also be beneficial for industry professionals in the allied fields.