This textbook is designed for first-year engineering students and provides a fundamental understanding of chemistry principles essential for various engineering disciplines. The content is structured to bridge the gap between basic chemistry concepts and their practical applications in engineering. Key Topics Covered: Atomic Structure and Periodic Table: Introduction to atoms and molecules. Atomic structure, electronic configuration, and periodic trends. Chemical Bonding: Ionic and covalent bonding. Molecular geometry and hybridization. Stoichiometry: Balancing chemical equations. Mole concept and stoichiometric calculations. States of Matter: Properties of gases, liquids, and solids. Phase diagrams and changes of state. Thermodynamics: Basic concepts of energy and the laws of thermodynamics. Heat transfer and thermodynamic cycles. Chemical Kinetics: Reaction rates and mechanisms. Factors influencing reaction rates. Chemical Equilibrium: Le Chatelier's principle. Equilibrium constants. Acids and Bases: Definitions of acids and bases. pH scale and buffer solutions. Electrochemistry: Redox reactions. Electrochemical cells and batteries. Materials and Polymers: Introduction to materials science. Polymer chemistry and applications. Environmental Chemistry: Pollution and its control. Green chemistry principles. Introduction to Organic Chemistry: Basic concepts of organic chemistry. Functional groups and their properties. The book may also include practical examples, case studies, and engineering applications to illustrate the relevance of chemistry in real-world engineering scenarios. Additionally, it might incorporate problem-solving exercises and questions to help students reinforce their understanding of the material.