exothermic

American  

[ek-soh-thur-mik] / ˌɛk soʊˈθɜr mɪk /

Or exothermal

adjective

Chemistry.

1. noting or pertaining to a chemical change that is accompanied by a liberation of heat (endothermic ).

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exothermic British  

/ ˌɛksəʊˈθɜːmɪk /

adjective

1. (of a chemical reaction or compound) occurring or formed with the evolution of heat Compare endothermic exoergic

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exothermic Scientific  

/ ĕk′sō-thûr′mĭk /

1. Relating to a chemical reaction that releases heat.

2. Compare endothermic

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Other Word Forms

• exothermally adverb
• exothermically adverb
• exothermicity noun

Etymology

Origin of exothermic

First recorded in 1880–85; exo- + thermic

Compare meaning

How does exothermic compare to similar and commonly confused words? Explore the most common comparisons:

• endothermic vs. exothermic

Example Sentences

On the other hand, if the solvation forces are much stronger than the compound’s electrostatic forces, the dissolution is significantly exothermic and the compound may be highly soluble.

From Textbooks • Feb. 14, 2019

Among other things, an ideal fuel for the control thrusters of a space vehicle should decompose in a spontaneous exothermic reaction when exposed to the appropriate catalyst.

From Textbooks • Feb. 14, 2019

The reaction of hydrogen with oxygen is a very exothermic reaction, releasing 286 kJ of energy per mole of water formed.

From Textbooks • Feb. 14, 2019

Both diagrams describe two-step, exothermic reactions, but with different changes in enthalpy, suggesting the diagrams depict two different overall reactions.

From Textbooks • Feb. 14, 2019

“The water creates an exothermic reaction—do you feel it warming up?”

From "The Running Dream" by Wendelin Van Draanen