Lesson eLearning

Which of the following statements correctly describes the effect of raising the temperature on the rate constant of a chemical reaction?

medium MCQ 1 mark Class 12 · Chemistry · Chemical Kinetics
  1. a) decreases because molecules move slower.
  2. b) remains unchanged because activation energy is constant.
  3. c) increases exponentially according to the Arrhenius equation.
  4. d) increases linearly with temperature.
Answer
c) increases exponentially according to the Arrhenius equation.

The correct answer is c) increases exponentially according to the Arrhenius equation. — Option (c) matches this behaviour; the other options contradict the equation.

Step-by-step solution

  1. Recall the Arrhenius equation: .
  2. An increase in temperature reduces the exponent , making larger.
  3. Therefore grows exponentially with , not linearly or inversely.
  4. Option (c) matches this behaviour; the other options contradict the equation.
Common mistake: Choosing the linear‑increase option because of the word ‘increase’ without considering the exponential form.

Concept tested: Temperature dependence of $k$ (Arrhenius)

Published · How this solution was prepared and checked

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