Question

Catalysts increase reaction rates by ________?

1) Decreasing the activation energy
2) Increasing the concentration of reactants
3) Decreasing the concentration of reactants
4) Increasing the temperature

Answer 1

Catalysts increase reaction rates by decreasing the activation energy, enabling more effective collisions between reactant molecules without changing their concentration or the reaction temperature.

Step-by-step explanation:

Catalysts increase reaction rates by decreasing the activation energy required for a reaction. This is achieved by providing an alternative pathway with a lower activation energy, which allows more reactant molecules to have effective collisions necessary to form products. Catalysts do not affect the concentration of reactants, nor do they change the temperature of the reaction system. Unlike other methods of increasing reaction rates, such as increasing the concentration or temperature which enhance the frequency of molecular collisions, catalysts modify the reaction mechanism and lower the energy barrier without being consumed by the reaction.