Which of the following statements is true about catalysts?

• A. A catalyst is always required in stoichiometric amounts.
• B. A catalyst increases the rate of a chemical reaction without being consumed in the process.
• C. A catalyst alters the equilibrium position of a chemical reaction.
• D. A catalyst decreases the activation energy by changing the reactants into different products.

Answer: (B)

Verified step by step guidance

1. Understand the definition of a catalyst: A catalyst is a substance that increases the rate of a chemical reaction without being consumed or permanently altered in the process.
2. Recall that catalysts are not required in stoichiometric amounts because they are not used up; they participate in the reaction mechanism but are regenerated at the end.
3. Recognize that catalysts do not change the equilibrium position of a reaction; they only help the system reach equilibrium faster by lowering the activation energy.
4. Know that catalysts lower the activation energy by providing an alternative reaction pathway, but they do not change the reactants into different products; the products remain the same.
5. Based on these points, identify the true statement: 'A catalyst increases the rate of a chemical reaction without being consumed in the process.'