Step-by-step explanation:
According to collision theory, more is the number of collisions occurring between the combining substances more will be the rate of reaction.
Factors that affect rate of a reaction are as follows.
Temperature - Increase in temperature leads to increase in kinetic energy of particles due to which there occurs more number of collisions between them. As a result, rate of reaction will increase leading to increase in rapid formation of products.
Surface area - More is the surface area of a substance, less will be the interaction between solute and solvent particles. And, when there occurs decrease in surface area then interaction between solute and solvent particles increases. This leads to increase in rate of reaction.
Concentration of reactants - More is the concentration of reactant molecules more is the availability of molecule interaction. As a result, more number of collisions occur leading to increase in rate of a reaction.