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Secondary IV • 1yr.

Hello,

I have trouble differentiating between exothermic and endothermic reactions according to their enthalpies. Do you have any tips or summaries?

Chemistry
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Explanations (1)

  • Explanation from Alloprof

    Explanation from Alloprof

    This Explanation was submitted by a member of the Alloprof team.

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    Team Alloprof • 1yr. edited September 2021

    Hi mangousteagile51!

    To understand the concept of enthalpy associated with endothermic and exothermic reactions, we must think of enthalpy as energy. The notation is often in the form of enthalpy difference (△ H). During an endothermic reaction, heat is absorbed, which implies that energy is absorbed. Therefore, the difference in energy is positive and the difference in enthalpy is positive as well:

    +△H ⇒ Endothermic


    As regards the exothermic reaction, there may be a loss of energy. So the difference in enthalpy is negative:


    -△H ⇒ Exothermic

    If you need more details, I invite you to consult our fact sheet on the subject! :)


    Let us know if we can help you with anything else!

    -Marilee