alleryStart learning →What effect does adding a catalyst have on the equilibrium constant of a reaction?
AIt raises the constant in every case
BIt lowers the constant in every case
CIt leaves the constant entirely unchanged
DIt changes the constant only above 100 C
Answer & Solution
Correct answer: C. It leaves the constant entirely unchanged
1. A catalyst speeds up the forward reaction and the reverse reaction by the same factor.
2. Because both rates rise together, the balance point between them does not move.
3. The equilibrium constant and the equilibrium concentrations are therefore unchanged.
4. What a catalyst does change is how quickly that same equilibrium is reached.
_Source: OpenStax Chemistry (CC BY 4.0), Ch 13 "Fundamental Equilibrium Concepts", section 13.3 Shifting Equilibria: Le Châtelier's Principle_
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