|Definition:|| form of energy related to chaotic microscopic behaviour of a system, given by the difference between the increase of the total energy of a closed system and the work done on the system, during a process of energy transfer|
NOTE 1 Amount of heat is a process quantity, not a state quantity. It depends on how the change from one state to another has been obtained and is only partly transformable into work.
NOTE 2 A supply of heat may correspond to an increase of thermodynamic temperature or to other effects, such as phase transition or chemical processes.
NOTE 3 The coherent SI unit of amount of heat is joule, J.