Reaction inhibitor

A reaction inhibitor is a substance that decreases the rate of, or prevents, a chemical reaction.A catalyst, in contrast, is a substance that increases the rate of a chemical reaction. A reaction inhibitor is a substance that decreases the rate of, or prevents, a chemical reaction.A catalyst, in contrast, is a substance that increases the rate of a chemical reaction. 2H2O2 → 2H2O + O2, which is catalyzed by heat, light, and impurities. An inhibitor can reduce the effectiveness of a catalyst in a catalysed reaction (either a non-biological catalyst or an enzyme). E.g., if a compound is so similar to (one of) the reactants that it can bind to the active site of a catalyst but does not undergo a catalytic reaction then that catalyst molecule cannot perform its job because the active site is occupied. When the inhibitor is released, the catalyst is again available for reaction.