Which of the following statements about catalysts and inhibitors is correct?

• A. Both a catalyst and an inhibitor increase the amount of product formed.
• B. Neither a catalyst nor an inhibitor changes the amount of product formed; they only affect the rate of the reaction.
• C. A catalyst or an inhibitor changes the amount of product formed in a chemical reaction.
• D. A catalyst increases the amount of product formed, while an inhibitor decreases it.

Answer: (B)

Verified step by step guidance

1. Step 1: Understand the role of a catalyst in a chemical reaction. A catalyst provides an alternative reaction pathway with a lower activation energy, which increases the rate at which the reaction reaches equilibrium, but it does not change the equilibrium position or the total amount of product formed.
2. Step 2: Understand the role of an inhibitor. An inhibitor slows down the reaction rate by interfering with the catalyst or the reaction mechanism, but like a catalyst, it does not affect the final amount of product formed once the reaction reaches equilibrium.
3. Step 3: Recall the concept of chemical equilibrium. The amount of product formed in a reaction is determined by the equilibrium constant, which depends on the thermodynamics of the reaction, not on the presence of catalysts or inhibitors.
4. Step 4: Analyze the given statements in light of these concepts. Since catalysts and inhibitors only affect the rate (how fast equilibrium is reached) and not the equilibrium position (how much product is formed), statements claiming changes in product amount are incorrect.
5. Step 5: Conclude that the correct statement is: Neither a catalyst nor an inhibitor changes the amount of product formed; they only affect the rate of the reaction.