How does increasing the surface area of one or more reactants affect the rate of a chemical reaction?

• A. It increases the reaction rate by allowing more collisions between reactant particles.
• B. It decreases the reaction rate by reducing the energy of collisions.
• C. It has no effect on the reaction rate.
• D. It slows down the reaction by limiting the availability of reactants.

Answer: (A)

Verified step by step guidance

1. Understand that the rate of a chemical reaction depends on how often reactant particles collide with enough energy to react.
2. Recognize that increasing the surface area of a reactant means breaking it into smaller pieces or spreading it out, which exposes more particles to the other reactants.
3. More exposed particles lead to a higher frequency of collisions between reactant particles per unit time.
4. Since reaction rate is proportional to the number of effective collisions, increasing surface area increases the reaction rate.
5. Therefore, increasing surface area does not reduce collision energy or limit reactant availability; instead, it enhances the chance of collisions, speeding up the reaction.