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Endothermic and exothermic reactions

In this post, we’ll look at endothermic and exothermic reactions.

Endothermic reactions

  • An endothermic reaction is one in which heat is absorbed from the surrounding.
  • As such, there is a decrease in temperature.
  • The enthalpy change (∆H) is positive.
  • Bond breaking is endothermic.
  • An endothermic reaction is one in which the bonds broken are stronger than the bonds formed.

Exothermic reactions

  • An exothermic reaction is one in which heat is given out to the surrounding.
  • As such, there is an increase in temperature.
  • The enthalpy change (∆H) is negative.
  • Bond forming is exothermic.
  • An exothermic reaction is one in which the bonds formed are stronger than the bonds broken.

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