The book is strictly revised in accordance with the recently updated syllabus issued by CISCE, New Delhi. Each chapter carries quite a good number of solved as well as unsolved numericals. NCERT Problems with their solutions have also been added for the benefit of the students. At the end of each chapter a large number of questions are given which are divided into different categories, such as Objective Type, Very Short-Answer Type, Short-Answer Type and Long-Answer Type [A], Long-Answer Type [B], Numericals and For Different Competitive Examinations. The order of questions and numericals in each category is strictly the same as the order of topics in the text matter. Except Long-Answer Type Questions, all other questions have been supported with answers or hints as necessary. Under the heading ‘For Different Competitive Examinations’, Objective and Multiple-Choice Type questions have been divided into two categories : [A] Multichoice Questions (Having Only One Correct Option) and [B] Multichoice Questions (Having One or More than One Correct Option). These questions have been supported by hints and solutions. Entire book has been thoroughly revised to make it free from errors.