This book, based on the BSEB syllabus, is meant for class 10 students. Important concepts have been stated in simple, lucid language, supported by figures. Solved numerical questions have been included in each chapter. Points to Remember is given at the end of all chapters for revision. The exercises include all types of questions asked in the examination. A chapter on practicals is also given in the book and includes viva-voce and multiple-choice questions.