Why does increasing the temperature generally alter the rate of a chemical reaction?

• A. It increases the kinetic energy of molecules, leading to more frequent and energetic collisions.
• B. It changes the chemical identity of the reactants.
• C. It increases the concentration of reactants in the reaction mixture.
• D. It decreases the activation energy required for the reaction to occur.

Answer: (A)

Verified step by step guidance

1. Understand that the rate of a chemical reaction depends on how often and how effectively reactant molecules collide with each other.
2. Recall that temperature is a measure of the average kinetic energy of molecules in a substance; increasing temperature means molecules move faster.
3. Recognize that faster-moving molecules collide more frequently and with greater energy, increasing the chances that collisions overcome the activation energy barrier.
4. Know that activation energy is the minimum energy required for a reaction to proceed, but temperature does not change this energy barrier itself.
5. Conclude that increasing temperature increases reaction rate primarily by increasing molecular kinetic energy, leading to more frequent and energetic collisions.