Question

Adding a catalyst to a reaction at equilibrium
A. changes Q
B. changes `K_(eq)`
C. changes both `Q` and `K_(eq)`
D. changes neither `Q` nor `K_(eq)`

Answer 1

Correct Answer - D
Adding a catalyst to a reaction at equilibrium has no effect on the value of Q and `K_(aq)` because a catalyst affects the activation energy of both forward and reverse reactions equally. It changes both rate constants `(K_(f)` and `K_(b))` by the same factor. So their ratio, `K_(aq)`, does not change.