Noteworthy features of the book: 1) Each topic has been dealt with in simple, easy and understandable language. 2) Important facts in the text have been highlighted. 3) every attempt has been made to connect fundamental ideas to their applications in solving numerical problems in physical Chemistry. 4) mechanisms of various important name reactions are discussed at relevant places to make the concepts more clear in Organic Chemistry. 5) Each Unit has solved very Short Answer questions, short Answer questions and Long Answer Questions including numerical and ISC examination questions of previous years. Appendices at the end of the chapters contain: (a) important tips for practical's (B) important name reactions (C) typical Organic conversions: Aliphatic conversions, Aromatic conversions and Carbohydrates distinction between pairs of Compounds (e) identification of unknown Organic Compounds/reagents (brf) problems based on Organic reactions Atomic masses of some common elements * ISC XII (2020) questions Paper (Solved) has been included. Further, ISC (2018) Specimen questions (Solved), four model test papers (Solved) and five Self-Practice Test Papers have been included to help the students prepare for the final ISC examination. * to gauge the preparedness of the students for the examination, A mock Examination Paper has also been provided at the end of the book.