What happens to the rate of a chemical reaction when an appropriate positive catalyst is added?
Answer and explanation
Correct answer: C. It increases
- Step 1: A catalyst speeds up both forward and reverse reaction rates equally.
- Step 2: It achieves this by providing an alternative reaction mechanism with a lower activation energy barrier (E_a).
Answer
It increases.
Why not the others: 'It decreases' describes an endothermic inhibitor; 'It remains unchanged' is false since catalysts do not alter Delta H; 'It stops the reverse reaction entirely' violates the principle of microscopic reversibility.
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