Activation energy

Minimum energy required for a chemical reaction

In the Arrhenius model of reaction rates, activation energy is the minimum amount of energy that must be available to reactants for a chemical reaction to occur. The activation energy (Ea) of a reaction is measured in kilojoules per mole (kJ/mol) or kilocalories per mole (kcal/mol). Simplified: Activation energy is the minimum energy barrier that reactant molecules must overcome to transform into products.

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