What happens to the speed of a reaction when a catalyst is used?

When a catalyst is introduced into a chemical reaction, it provides an alternative pathway for the reaction to occur, which has a lower activation energy compared to the uncatalyzed pathway. This lower activation energy allows more reactant molecules to have sufficient energy to successfully collide and form products within a given time frame. As a result, the overall speed of the reaction increases.

Importantly, a catalyst is not consumed during the reaction; it can participate in the reaction mechanism but is regenerated by the end of the process. Therefore, it can facilitate the reaction without decreasing in quantity, allowing it to speed up ongoing reactions and any future reactions it is involved in. This characteristic makes catalysts valuable in many industrial applications and biological processes.

Additionally, while catalysts can significantly enhance the rate of both endothermic and exothermic reactions, the focus here is primarily on how they affect the reaction speed, not the type of reaction. Thus, the correct understanding of a catalyst’s role is that it increases the rate of reaction, confirming that the speed of the reaction accelerates when a catalyst is applied.