Answer: Does not change the position of equilibrium.
- A Shifts equilibrium toward the exothermic direction
- B Shifts equilibrium toward the endothermic direction
- C Increases the value of the equilibrium constant Kc
- D Does not change the position of equilibrium
Correct answer: D. Does not change the position of equilibrium
Explanation: A catalyst speeds up both forward and reverse reactions equally, so Kc and equilibrium position are unchanged.
As the reaction proceeds, reactant concentration falls and product concentration rises until both level off at equilibrium.
Concept context
When forward and reverse reaction rates are equal, equilibrium is reached. Learn about Kc, Kp, Le Chatelier's principle, and acid-base equilibria, including pH, buffer solutions, and solubility product.