(i) Rate of a reaction increases with increase in temperature.

(ii) Rate of a reaction increases with a decrease in activation energy.

(iii) Rate constant decreases exponentially with an increase in temperature.

(iv) Rate of reaction decreases with a decrease in activation energy.

Correct Answers:

(i) Rate of a reaction increases with increase in temperature

(ii) Rate of a reaction increases with a decrease in activation energy

Explanation: In accordance with the Arrhenius equation, the rate of the reaction increases with an increase in temperature and a decrease in the activation energy.