exotermie
Exotermie refers to a process that releases energy, usually in the form of heat, into its surroundings. This is in contrast to endothermic processes, which absorb energy. When a chemical reaction is exothermic, the total energy of the products is lower than the total energy of the reactants. This difference in energy is released as heat. Common examples of exothermic reactions include the combustion of fuels like wood or natural gas, where significant heat is generated. The burning of a match or the explosion of fireworks are also exothermic events. The formation of strong chemical bonds in the products contributes to the energy release. The term can also be applied to physical processes. For instance, when water freezes, it releases latent heat, making it an exothermic phase change. Conversely, melting ice is an endothermic process, requiring heat input. Measuring the heat released or absorbed in a process is often done using calorimetry. Understanding exotermie is fundamental in many scientific and engineering fields, from chemistry and physics to environmental science and materials science. It plays a role in everything from biological metabolism to industrial chemical synthesis.