In an exothermic chemical reaction the energy gained by the surroundings must be the energy lost by the reaction

The energy gained by the surroundings must be greater than the energy lost by the reactants in an exothermic reaction.

Explanation:

Exothermic reaction is a chemical reaction in which the energy from the reaction is transferred to the surroundings and so the products and the reactants in the reaction have lesser energy compared to the energy gained by the surroundings.

For example, thermal decomposition of compounds in carbonates. So it must be greater than the energy that is lost by the reactants in an exothermic reaction.

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