This textbook has been designed to meet the needs of B.Sc. First Semester students of Chemistry as per the UGC Choice Based Credit System (CBCS). With its traditional approach to the subject, this textbook lucidly explains principles of chemistry. Important topics such as atomic structure, chemical bonding, molecular structure, fundamentals of organic chemistry, stereochemistry and aliphatic hydrocarbons are aptly discussed to give an overview of inorganic and organic chemistry. Laboratory work has also been included to help students achieve solid conceptual understanding and learn experimental procedures.