A catalyst is a substance that: MCQ with Answer and Explanation

A catalyst is a substance that:
A. Changes the equilibrium constant of a reaction.
B. Is completely consumed in the reaction.
C. Increases the activation energy of a reaction.
D. Alters the rate of a chemical reaction without being consumed.
Answer: Option D
Solution (By JKExamLibrary)
A catalyst speeds up (positive catalyst) or slows down (negative catalyst) a chemical reaction by providing an alternative pathway with a lower (or higher) activation energy. It remains chemically unchanged and in the same amount at the end of the reaction, and does not alter the equilibrium position.

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