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How does microscopic reversibility relate the forward and reverse pathways of a 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).

The principle of microscopic reversibility provides a dynamic description of a system at equilibrium. It states that at the atomic or molecular level, a system in equilibrium is not static; rather, there is continuous activity where the forward and reverse rates of a reaction are exactly equal.1

In the context of a chemical reaction, this means that the amount of reactants being converted into products per unit time is precisely matched by the amount of products being converted back into reactants. Because these processes occur at the same rate, there is no net change in the concentration of substances on a macroscopic scale.1

When applied to reactions that proceed through multiple steps, this concept is known as the principle of detailed balancing, which dictates that each individual step must have equal forward and reverse rates at equilibrium. Furthermore, for a single-pathway reaction at equilibrium, the principle implies that the specific course taken by the reverse reaction is statistically identical to the path taken by the forward reaction.12