Question

how does a catalyst work?
○ by increasing the temperature of a chemical reaction
○ by decreasing the pressure of a chemical reaction
○ by increasing the concentration of reactants in a reaction
○ by decreasing the activation energy of a reaction

Explanation:

A catalyst is a substance that speeds up a chemical reaction without being consumed in the process. The key mechanism of a catalyst is to lower (decrease) the activation energy required for the reaction to occur. Increasing temperature, decreasing pressure, or increasing reactant concentration are other factors that can affect reaction rates but are not how a catalyst functions.

Answer:

D. by decreasing the activation energy of a reaction