Which of the following will increase the rate of a chemical reaction?

• A. Decreasing the temperature
• B. Increasing the concentration of reactants
• C. Lowering the surface area of a solid reactant
• D. Adding an inert gas at constant volume

Answer: (B)

Verified step by step guidance

1. Understand that the rate of a chemical reaction depends on factors that affect how often and how effectively reactant particles collide.
2. Recall that increasing the concentration of reactants increases the number of particles per unit volume, leading to more frequent collisions and thus a higher reaction rate.
3. Recognize that decreasing the temperature generally slows down the reaction because particles have less kinetic energy, resulting in fewer effective collisions.
4. Know that lowering the surface area of a solid reactant reduces the area available for collisions, which decreases the reaction rate.
5. Understand that adding an inert gas at constant volume does not change the concentration of reactants, so it does not affect the reaction rate.