Given the task definition and input, reply with output. In this task, we ask you to elaborate the sentence without changing its general meaning. You can do so by explaining further the input sentence, using more precise wording, adding qualifiers and auxiliary information etc.

The activation energy of a chemical reaction is the minimum energy that is needed to make the reaction happen .

In chemistry and physics , activation energy is the energy which must be provided to a chemical or nuclear system with potential reactants to result in : a chemical reaction , nuclear reaction , or various other physical phenomena .