A catalyst increases the rate of a chemical reaction by:

• A. lowering the activation energy required for the reaction
• B. raising the temperature of the reaction mixture
• C. providing additional reactants to the system
• D. increasing the equilibrium constant of the reaction

Answer: (A)

Verified step by step guidance

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 reaction rate without being consumed in the process.
2. Recall that activation energy is the minimum energy required for reactants to transform into products; lowering this energy barrier allows more molecules to react at a given temperature.
3. Recognize that a catalyst does not change the temperature of the reaction mixture; temperature is an external condition that affects reaction rate independently.
4. Note that a catalyst does not add reactants to the system; it only affects how quickly the existing reactants convert to products.
5. Understand that a catalyst does not change the equilibrium constant of the reaction; it speeds up the rate at which equilibrium is reached but does not alter the position of equilibrium.