The book 'Thermochemistry' takes the readers through the various aspects related to the areas in which thermodynamics finds its application in the field of chemistry. When the reactions take place, there is definite exchange of heat between the chemicals and the surroundings. Thermochemistry deals with the heat related aspects of the various chemical processes and finds the ways in which these processes can be applied for good and constructive use in the industry. This book makes the readers aware about the basic concepts of thermochemistry.