Which term best describes a substance that influences the rate of a chemical reaction but is not consumed or permanently changed by the reaction?

• A. Solvent
• B. Catalyst
• C. Product
• D. Reactant

Answer: (B)

Verified step by step guidance

1. Understand the role of each term in a chemical reaction: Reactants are substances that start a reaction, Products are substances formed by the reaction, Solvents are mediums in which reactions occur but do not directly influence the reaction rate.
2. Focus on the definition of a substance that influences the rate of a chemical reaction without being consumed or permanently changed.
3. Recall that a Catalyst is a substance that increases or decreases the rate of a chemical reaction without undergoing permanent chemical change itself.
4. Compare the given options with the definition: Reactants and Products are consumed or formed, Solvents do not typically influence reaction rates, but Catalysts do and remain unchanged.
5. Conclude that the term 'Catalyst' best fits the description of a substance that influences the rate of a chemical reaction without being consumed or permanently changed.