Explain Collision Theory Practice Test

A solid reactant is tested in two forms: a single large chunk and a fine powder. The powder reacts noticeably faster when placed into the same liquid reactant. Using collision theory, what is the best particle-level reason for the faster reaction with the powder?

A reaction between dissolved ions begins immediately after two solutions are mixed, but the reaction is still noticeably faster when the mixture is stirred continuously. Which collision-theory explanation best accounts for stirring increasing the reaction rate?