A student grinds a coarse crystalline solid into a fine powder before mixing it with…
CHEMISTRY · Single correct · A Level · Chemistry · Kinetics · Kinetics
Problem
A student grinds a coarse crystalline solid into a fine powder before mixing it with an aqueous reagent under otherwise identical conditions. Which of the following best describes the expected effect on the initial rate of the reaction?
(a) The rate increases because the activation energy is lowered by grinding the solid, making it easier for the reaction to occur.
(b) The rate increases because the larger total surface area allows more collisions per unit time.
(c) The rate is unchanged because surface area does not affect reactions that occur in solution.
(d) The rate increases because grinding produces a greater molar concentration of the reactant in the mixture.