How does a catalyst increase the rate of a chemical reaction?

• A. It provides additional reactants for the reaction.
• B. It raises the temperature of the reaction mixture.
• C. It increases the equilibrium constant of the reaction.
• D. It lowers the activation energy required for the reaction to occur.

Answer: (D)

Verified step by step guidance

1. Understand that a catalyst is a substance that increases the rate of a chemical reaction without being consumed in the process.
2. Recall that the rate of a chemical reaction depends on the activation energy, which is the minimum energy required for reactants to transform into products.
3. Recognize that a catalyst works by providing an alternative reaction pathway with a lower activation energy compared to the uncatalyzed reaction.
4. Note that lowering the activation energy means more reactant molecules have enough energy to overcome this barrier at a given temperature, thus increasing the reaction rate.
5. Understand that a catalyst does not change the temperature, the equilibrium constant, or the amount of reactants; it only affects the speed at which equilibrium is reached by lowering the activation energy.