This book College Chemistry, Grade XII is an outcome of overwhelming response that we had from our valued readers, teachers and students from different colleges, guardians and well wishers. At this juncture, we extend our heartfelt gratitude to all.

The contents of the book have been revised and improved in accordance with the need of the new syllabus prescribed by Curricuclum Development Center (CDC), Sanothimi, Bhaktapur, Nepal. We hope this edition fulfills the requirement of complete syllabus. The authors have ceaselessly worked hard to make this book a complete text book of biology for grade XII. Each lesson has been properly scrutinized and its classroom implication has seen well assessed. We believe this endeavour will further ensure students’ success in competitive examinations of different kinds along with qualifying themselves for college/university degrees.

We are very grateful to the students and teachers for the utmost response they have provided with zeal to our text book of Grade XII entitled as “College Chemistry – Grade XII”.

An attempt has been made to keep the language simple and lucid to help the students (as well as readers and teachers) understand the subject matter clearly.

The salient features of this text book are as follows:

1. A large number of numerical problems illustrate the applications of various concepts described as well as the unsolved numerical problems.
2. Solved questions

iii.     Exercises

• Very Short Answer Questions
• Short Answer Questions
• Long Answer Questions

The above mentioned features on the whole provide the students with the following performances.

1. to get familiar with the subject matter well
2. to meet the educational role of science students of Grade XII for competitive examinations in medicines, engineering and others

iii.     to seek the knowledge.

It is hoped that those features will make the book more useful and interesting as well to the students. We are highly oblized to various personalities who gave invaluable support and encouragement directly or indirectly or indirectly to make this book produce.

The authors sincerely hope that the book will immensely benefit the readers. Despite our best efforts, there may be some errors are brought to our notice.

We are thankful to Mr. Basant Raj Pokherel, Mr. Buddhi Tiwari and Mr. Resham shrestha of the Ayam Publications for the great efforts to get this book published.

Any suggestions from the readers for the improvement of the book will be gratefully acknowledged to improve this College Chemistry – Grade XII further.