Destroyed or altered by heat.
- Heat of formation
noun 1. (chem) the heat evolved or absorbed when one mole of a compound is formed from its constituent atoms
noun, Physics. 1. the heat absorbed by a unit mass of a given solid at its melting point that completely converts the solid to a liquid at the same temperature: equal to the heat of solidification. heat of fusion The amount of heat required to convert a solid at its melting point into a liquid […]
- Heat of reaction
noun 1. (chem) the heat evolved or absorbed when one mole of a product is formed at constant pressure
noun, Physics. 1. the heat liberated by a unit mass of liquid at its freezing point as it solidifies: equal to the heat of fusion.