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According to the Arrhenius equation, which of the following statements is/are correct?

1. A high activation energy usually implies a fast reaction
2. The rate constant increases with increasing temperature because more collisions have energy exceeding the activation energy
3. A higher activation energy means a stronger dependence of the rate constant on temperature
4. The pre-exponential factor measures the rate at which collisions occur, regardless of their energy

Correct answer: The rate constant increases with increasing temperature because more collisions have energy exceeding the activation energy

Solution

Option A is FALSE: high Ea means the exponential factor exp(-Ea/RT) is small, making k small and the reaction slow. Option B is TRUE: higher T raises the fraction of molecules with energy >= Ea. Option C is TRUE: d(ln k)/dT = Ea/(RT²); larger Ea means k changes more steeply with T. Option D is TRUE: A (pre-exponential/frequency factor) = rate of collisions irrespective of energy. Correct statements: B, C, D.

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