Which of the following best describes how temperature affects the rate of a chemical reaction?

• A. Increasing temperature generally increases the rate of reaction by providing more kinetic energy to the reactant molecules.
• B. Temperature has no effect on the rate of a chemical reaction.
• C. Decreasing temperature always increases the rate of reaction.
• D. Increasing temperature generally decreases the rate of reaction by slowing down molecular motion.

Answer: (A)

Verified step by step guidance

1. Understand that the rate of a chemical reaction depends on how often and how energetically reactant molecules collide.
2. Recall the collision theory, which states that molecules must collide with sufficient energy (activation energy) and proper orientation for a reaction to occur.
3. Recognize that increasing temperature increases the average kinetic energy of molecules, causing them to move faster and collide more frequently and with greater energy.
4. Conclude that because more molecules have enough energy to overcome the activation energy barrier at higher temperatures, the reaction rate generally increases.
5. Note that decreasing temperature reduces molecular kinetic energy, leading to fewer effective collisions and a slower reaction rate.