Final answer:
A catalyst speeds up the rate at which a chemical reaction reaches equilibrium but does not change the amounts of products and reactants at equilibrium. It indicating that only the time to reach equilibrium is affected. Therefore, the correct option is B.
Step-by-step explanation:
The impact of a catalyst on equilibrium is an important concept in chemical kinetics. A catalyst is a substance that increases the speed of a chemical reaction without itself being consumed or altered in the process. When it comes to an equilibrium reaction, the role of a catalyst is to decrease the time it takes for the system to reach equilibrium. However, a catalyst does not alter the position of the equilibrium or the amounts of products and reactants present when equilibrium is attained. Therefore, the correct answer to the question is that a catalyst decreases the time it takes to reach equilibrium but doesn't affect the amounts of products and reactants. This means option b) is accurate: A catalyst does not change the composition of the equilibrium mixture, the equilibrium constant (K), or the concentrations of the reactants and products at equilibrium. Adding a catalyst will equally speed up both the forward and reverse reactions, thus not disturbing the equilibrium state once it is achieved. This principle applies to many industrial and biological processes, such as the synthesis of ammonia, where catalysts play a significant role in increasing production efficiency.