This book describes the importance of chemistry in chemical engineering. People who don t like chemistry; they do not prefer chemical engineering branch as they believe that chemical engineer has to learn chemistry in much detail which is not correct, but yes they have to learn at least basic fundamentals of chemistry to understand the chemical engineering as chemical engineering basically is an applied chemistry. They need not to go into the depth of molecular or atomic level concept of chemistry but they should know at least basic concepts of chemistry which are very useful to solve their practical problems in their technical field. With this book author has tried to build a bridge between these two branches and tried to explain how these two branches are inter linked.