Concept:The rate of a chemical reaction is determined by factors that influence how often and how effectively reactant particles collide.
Explanation:Concentration of reactants, temperature, and a catalyst all directly affect the frequency or energy of collisions between reacting particles.
Increasing concentration or temperature raises collision frequency or energy, while a catalyst provides an alternative pathway with lower activation energy.
The molecular weight of products, however, is a property of the substances formed after the reaction and does not influence the speed at which the reaction proceeds.
Therefore, molecular weight of products is not a factor that affects reaction rate.
Answer:C. Molecular weight of products