Catalyst is a substance that speeds up the rate of a chemical reaction.

Catalyst is a substance that speeds up the rate of a chemical reaction.

• A. A substance that slows down a reaction
• B. A substance that speeds up a chemical reaction
• C. A substance that neutralizes acids
• D. A substance that dries a cement

Answer: (B)

A catalyst speeds up a chemical reaction by providing an alternate pathway with lower activation energy. That means more particles have enough energy to react at the same temperature, so the reaction proceeds faster. The catalyst isn’t consumed in the process, so it can continue to catalyze multiple cycles, and it generally speeds up how fast the system reaches equilibrium without changing the final amount of products. This idea matches the statement that a catalyst is a substance that speeds up a chemical reaction. By contrast, something that slows a reaction would be an inhibitor, not a catalyst. A substance that neutralizes acids relates to acid-base chemistry rather than reaction rate, and something that dries cement refers to the setting process rather than catalytic speed.

A catalyst speeds up a chemical reaction by providing an alternate pathway with lower activation energy. That means more particles have enough energy to react at the same temperature, so the reaction proceeds faster. The catalyst isn’t consumed in the process, so it can continue to catalyze multiple cycles, and it generally speeds up how fast the system reaches equilibrium without changing the final amount of products.

This idea matches the statement that a catalyst is a substance that speeds up a chemical reaction. By contrast, something that slows a reaction would be an inhibitor, not a catalyst. A substance that neutralizes acids relates to acid-base chemistry rather than reaction rate, and something that dries cement refers to the setting process rather than catalytic speed.