What is required for reactants to form bonds?

energy input

Explanation:

Chemical reactions are the result of the transformation that takes place in substances (the reactants), where atoms rearrange themselves to their initial state, transforming them into what we call "resultants." Thus, chemical compounds undergo changes generating new molecules. For the reaction to occur it is necessary that there is already an energy input during the handling of the reagents. This energy will be used to rearrange the reagent atoms.

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