Calorimetry, or heat measurement, is a branch of physics that deals with the measurement of heat quantities. The specific heat of substances, heat of transfer, thermal effects of chemical reactions, calorific value of fuels etc. are determined calorimetrically. Calorimeters are used to measure amounts of heat. The amount of heat is found from the change in temperature of a certain amount of water or other liquid in the calorimeter, caused by the heat effect of the process being studied.