Exothermic Reaction - GCSE Biology Definition

Reviewed by: Lára Marie McIvor

Published

An exothermic reaction is a type of chemical reaction that releases energy into the surroundings, usually in the form of heat or light. In these reactions, the total energy of the products is less than the total energy of the reactants, causing the extra energy to be given off. This is why you might feel heat coming from an exothermic reaction. A common example is when you burn wood or fuel, as the reaction releases energy that you can feel as heat or see as flames. Exothermic reactions are important in everyday processes and even in biological systems, like when our bodies break down food to release energy.

Examiner-written GCSE Biology revision resources that improve your grades 2x

  • Written by expert teachers and examiners
  • Aligned to exam specifications
  • Everything you need to know, and nothing you don’t
GCSE Biology revision resources

Share this article

Lára Marie McIvor

Reviewer: Lára Marie McIvor

Expertise: Biology, Psychology & Sociology Subject Lead

Lára graduated from Oxford University in Biological Sciences and has now been a science tutor working in the UK for several years. Lára has a particular interest in the area of infectious disease and epidemiology, and enjoys creating original educational materials that develop confidence and facilitate learning.

The examiner written revision resources that improve your grades 2x.

Join now