Final answer:
Increasing the concentration of reactants in a chemical reaction generally decreases the time required for the reaction to occur by increasing the rate of collision between reactant particles and enhancing enzyme activity.
Step-by-step explanation:
Increasing the concentration of a substance needed for a chemical reaction will decrease the time of the reaction.
Concentration plays a pivotal role in the rate of a chemical reaction. An increase in the concentration of reactants leads to more frequent collisions between reacting particles, resulting in an increased reaction rate. This is supported by collision theory, which explains how an increase in the number of reactive particles in a given space elevates the probability of collisions, thereby accelerating the reaction.
Furthermore, in the presence of an increased concentration, provided there is sufficient substrate or reactant, the activity of enzymes, which act as biological catalysts, is also elevated. This is because there are more substrate molecules available for the enzymes to convert into products, speeding up biochemical reactions as well.