Which of the following best describes the effect of increasing temperature on the rate of a chemical reaction?

• A. It decreases the reaction rate by slowing down molecular collisions.
• B. It increases the reaction rate by providing more kinetic energy to the reactant molecules.
• C. It causes the reaction rate to decrease because fewer molecules have enough energy to react.
• D. It has no effect on the reaction rate.

Answer: (B)

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 the Arrhenius equation, which relates the reaction rate constant \(k\) to temperature \(T\): \[k = A e^{-\frac{E_a}{RT}}\] where \(A\) is the frequency factor, \(E_a\) is the activation energy, \(R\) is the gas constant, and \(T\) is the temperature in Kelvin.
3. Recognize that increasing temperature \(T\) decreases the exponential term's denominator, making \(e^{-\frac{E_a}{RT}}\) larger, which increases the rate constant \(k\) and thus the reaction rate.
4. Understand that higher temperature means molecules have more kinetic energy, leading to more frequent and more energetic collisions, increasing the chance that molecules overcome the activation energy barrier.
5. Conclude that increasing temperature increases the reaction rate by providing more kinetic energy to the reactant molecules, making the correct description the one that states this effect.