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exothermic Syllabification: ex·o·ther·mic
Pronunciation: /ˌeksōˈTHərmik/

Definition of exothermic in English:


1(Of a reaction or process) accompanied by the release of heat. The opposite of endothermic (sense 1).
Example sentences
  • Sodium hydroxide dissolved into water is an exothermic process, ammonium nitrate dissolved in water is an endothermic process.
  • The rusting of iron is an exothermic reaction and this process is used in hand warmers which are utilized in cold regions.
  • When fireworks are ignited, the chemical compounds react with each other in an exothermic reaction - releasing energy.
1.1(Of a compound) formed from its constituent elements with a net release of heat.
Example sentences
  • Little heat is needed in the roasting of sulfide ores because the oxidation of the sulfide ion to sulfur dioxide is exothermic.


Late 19th century: from French exothermique.



Pronunciation: /-(ə)lē/
Example sentences
  • This is because fluorine generally reacts exothermically to form products with stable C-F bonds.

Definition of exothermic in:

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