endotermisk

Endotermisk is the adjective used to describe processes or reactions that absorb heat from their surroundings. The term, related to the English endothermic, is formed from Greek roots meaning within (endo) and heat (therm). In chemistry and physics, endotermiska processer have a positive enthalpy change (ΔH > 0), meaning they require heat input to proceed. In biology, the related concept of endothermy refers to organisms that regulate body temperature through internal metabolic heat production.

In thermodynamics, an endothermic process draws energy into the system, which can cause the surroundings to cool if not supplied from an external source. The rate and extent of such processes often depend on temperature and heat transfer. Endothermic reactions are commonly associated with phase changes, such as melting and vaporization, where energy is used to break intermolecular bonds rather than to raise the temperature of the substance.

Common examples of endothermic phenomena include photosynthesis in plants, which uses light energy to convert carbon dioxide and water into glucose and oxygen; melting ice, where solid water absorbs heat to become liquid; and evaporation, where liquid absorbs heat to become vapor. Some chemical reactions, such as the decomposition of certain salts or the dissolution of ammonium nitrate in water, are also endothermic.

In biology, endothermy describes warm-blooded organisms that maintain a relatively constant internal temperature through metabolic heat production and insulation. This capability supports activity across varied environments but increases energy requirements. Endotermisk concepts are contrasted with exothermic processes, where heat is released to the surroundings. See also endothermy, exothermic reactions, and phase transitions.