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Chemical Engineering vocabulary · Reactions and Reactors

Exothermic

Meaning in chemical engineering, with examples

/ˌɛksoʊˈθɜːrmɪk/adjectiveCore term

In chemical engineering, exothermic means: Describes a reaction or process that releases heat to its surroundings, such as combustion, neutralization or most polymerizations.

In Turkish: ekzotermik, ısı veren

How it is used

Used in reactor design and process safety. Strongly exothermic reactions need good cooling, controlled dosing and protection against runaway. Engineers say a reaction is 'highly', 'mildly' or 'strongly' exothermic and talk about the heat of reaction.

Example sentences

  1. The nitration is highly exothermic, so the acid is dosed slowly with full cooling.

  2. Because the reaction is exothermic, the outlet of the catalyst bed is 40 °C hotter than the inlet.

Common collocations

  • highly exothermic
  • exothermic reaction
  • heat of reaction
  • exotherm
  • endothermicDescribes a reaction or process that takes in heat from its surroundings, so heat has to be supplied to keep it going, as in steam reforming or cracking.
  • runaway reactionAn exothermic reaction that gets out of control: heat is produced faster than it can be removed, so temperature, reaction rate and pressure rise faster and faster.
  • enthalpyA measure of the heat content of a substance, used to calculate how much energy is needed to heat, cool, vaporize or react it at constant pressure. Usually given in kJ/kg or kJ/mol.
  • jacketAn outer shell around a reactor or vessel through which steam, hot oil or cooling water flows to heat or cool the contents.

This word in other fields

The same English word can have a different meaning in another field:

More terms: Reactions and Reactors

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