What is the main function of a catalyst in a chemical reaction?

The main function of a catalyst in a chemical reaction is to speed up the reaction rate by lowering the activation energy. A catalyst achieves this by providing an alternative reaction pathway that has a lower activation energy barrier compared to the uncatalyzed reaction. This allows more reactant molecules to have enough energy to overcome the energy barrier, thus increasing the rate at which products are formed.

Unlike other factors such as temperature or concentration, a catalyst does not alter the products of the reaction or change the amounts of the reactants involved. It remains unchanged after the reaction, making it reusable for subsequent reactions. This characteristic is fundamental to the role of catalysts in both biological systems, where enzymes act as biological catalysts, and in industrial processes to enhance yield and efficiency.