How does increasing temperature affect the rate of a chemical reaction?

How does increasing temperature affect the rate of a chemical reaction?

• A. It decreases the reaction rate.
• B. It has no effect on the reaction rate.
• C. It only affects the rate if a catalyst is present.
• D. It increases the reaction rate.

Answer: (D)

Rising temperature boosts reaction rate because it increases the average kinetic energy of the molecules. With higher temperature, more collisions have enough energy to overcome the activation barrier, so a larger fraction of collisions are productive. This raises the rate constant (as described by the Arrhenius relationship), making reactions go faster even without a catalyst. While catalysts lower the activation energy and can significantly speed up reactions, temperature itself also independently accelerates the process, so the overall effect is an increase in rate. The other statements—that temperature decreases the rate, or has no effect, or only affects the rate if a catalyst is present—don’t match how energy and collision frequency drive reaction kinetics.

Rising temperature boosts reaction rate because it increases the average kinetic energy of the molecules. With higher temperature, more collisions have enough energy to overcome the activation barrier, so a larger fraction of collisions are productive. This raises the rate constant (as described by the Arrhenius relationship), making reactions go faster even without a catalyst. While catalysts lower the activation energy and can significantly speed up reactions, temperature itself also independently accelerates the process, so the overall effect is an increase in rate. The other statements—that temperature decreases the rate, or has no effect, or only affects the rate if a catalyst is present—don’t match how energy and collision frequency drive reaction kinetics.