t gives me enormous pleasure to present the thoroughly revised, restructured, and enlarged Thirteenth Edition of the book ‘Nootan ISC Chemistry’ for Class XI. The warm welcome extended by the learned teachers and students to the earlier editions of this book is an asset to me and I am grateful to all those learned teachers and students who not only appreciated the subject matter and style of presentation but also took trouble in giving their suggestions for the further improvement of the book.
The book has been thoroughly revised and restructured in the light of the syllabus and the detailed scope of the syllabus issued by the Council for Indian School Certificate Examination, New Delhi. Several chapters have been rewritten and extra study material and new exercises have been added in most of the chapters. During the revision of the book, typographical errors, to the best of our efforts, have been rectified and every care has been taken to make the more difficult portions of the text easily understandable even by the average students. As suggested by some ISC teachers, a few topics not mentioned in ISC syllabus have been removed. In order to facilitate the Biology students, necessary hints to the mathematical treatments have been incorporated as footnotes. The Assertion-Reason Type Questions have been added in each unit. Since, the latest ISC syllabus is very much similar to NCERT syllabus, the NCERT Text-Book Exercises with necessary hints/solutions have also been added at the end of each unit. ‘The Self Assessment and Competition File’ containing a large number of different types of questions given at the end of each chapter is expected to help immensely the students to have an edge over others in assessing themselves and preparing for competitive examinations. The book is written in accordance to the latest trends in the subject and SI units have been used all over the text. Where ever necessary, conventional units have also been used.