What role does a catalyst play in a chemical reaction?

A catalyst is a substance that increases the rate of a chemical reaction by lowering the activation energy required for the reaction to proceed. Activation energy is the energy barrier that must be overcome for reactants to transform into products. By providing an alternative reaction pathway with a lower activation energy, catalysts facilitate the conversion of reactants into products more efficiently, without being consumed in the process.

This does not alter the overall energetics of the reaction or change the products formed. Instead, it simply makes it easier for the reaction to occur, allowing it to proceed more readily under a given set of conditions. Therefore, the role of a catalyst is fundamental in various biological and industrial processes, where enhancing reaction rates is crucial for efficiency.