Assertion (A): A catalyst does not change the equilibrium yield of a reaction. Reason (R): A catalyst speeds up both the forward and backward reactions equally. MCQ with Answer and Explanation

Assertion (A): A catalyst does not change the equilibrium yield of a reaction. Reason (R): A catalyst speeds up both the forward and backward reactions equally.
A. A is true but R is false.
B. A is false but R is true.
C. Both A and R are true but R is NOT the correct explanation of A.
D. Both A and R are true and R is the correct explanation of A.
Answer: Option D
Solution (By JKExamLibrary)
A catalyst lowers the activation energy for both the forward and reverse reactions by the same amount. Therefore, it increases the rates of both reactions equally, allowing the system to reach equilibrium faster, but without changing the final equilibrium concentrations (yield). Both statements are correct and R explains A.

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