Which is usually associated with a faster reaction rate? a. shaking pepper into the reactants b. removing heat energy from the reactants c. using a highly concentrated solution in the reactants d. using a solid with a low surface area in the reactants

C. Using a highly concentrated solution of the reactants  

Explanation:

If the solutions are more concentrated, there will be more collisions per second between the reactants, so the rate will be faster.

A. is wrong. Pepper might make you sneeze, but it won't make the reaction go any faster.

B is wrong. Removing heat will cause the molecules to slow down, so fewer of them will have energy to get over the activation energy barrier.

D. is wrong. If a reactant has a small surface area, fewer of the other reactant molecules will be able to collide with it, so the reaction will slow down.

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