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How is an addition reaction related to the reverse of an elimination reaction?

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dissociation of E–N — reaction mechanism Possible energy diagram for the dissociation of a covalent molecule, E–N, into its ions E⁺ and N⁻ (see text).

An addition reaction and an elimination reaction are formally related as reverse processes of one another.1

In an addition reaction, atoms or groups of atoms are added to a molecule, typically involving the breaking of double or triple bonds to accommodate these new substituents. Conversely, an elimination reaction involves the removal of a pair of atoms or groups from a molecule, which results in the formation of double or triple bonds.23

The relationship between these two processes is governed by the principle of microscopic reversibility. This principle states that at equilibrium, the forward and reverse rates of a reaction are equal, meaning the pathway taken to convert reactants to products is the same as the pathway taken to convert products back to reactants. Consequently, because elimination reactions can be treated as the formal reverse of additions, the mechanisms governing these transformations are fundamentally linked through this dynamic equilibrium.41