This book offers essential foundational knowledge in thermodynamics, chemical kinetics, and chemical reaction engineering, providing the tools necessary for a rational understanding of chemical processes and the unit operations that comprise them. Key topics include thermodynamic principles for pure fluids and mixtures, material and energy balances, reaction equilibrium (including systems with useful work), phase equilibrium in multicomponent systems, chemical kinetics, and the fundamentals of reaction engineering. Each chapter features detailed derivations, experimental observations, and worked examples, delivering practical insights into process solutions and real-world applications. Designed primarily for undergraduate students in Chemical Engineering, this book also serves as a valuable reference for professionals seeking a comprehensive review of principles applied to chemical process analysis and design.