Why does a higher concentration increase the rate of reaction?
a
It increases the frequency of collisions.
b
It decreases the amount of reactants.
c
It increases the surface area of the particles
d
It lowers the activation energy.
a) It increases the frequency of collisions.
The correct answer is a. Increasing the concentration of reactants in a chemical reaction increases the rate of reaction because it increases the frequency of collisions between the particles. When the concentration is higher, there are more particles per unit volume, leading to a greater chance of collisions between reacting molecules. Increased collisions result in a higher frequency of successful collisions, thereby increasing the rate of reaction.
The correct answer is a: It increases the frequency of collisions.
Explanation: In a chemical reaction, the rate of reaction is determined by how frequently reactant particles collide with each other. When the concentration of reactants is increased, there are more particles present in a given volume. As a result, the chance of these particles colliding with each other also increases. Therefore, a higher concentration of reactants leads to an increased frequency of collisions between the particles, ultimately increasing the rate of reaction.
To independently arrive at this conclusion, one can perform the following steps:
1. Recognize that the concentration of reactants refers to the amount of reactant particles (atoms or molecules) present in a given volume, usually measured in moles per liter (molarity, M).
2. Understand that the collision theory explains the connection between the rate of reaction and the frequency of collisions between reactant particles. According to this theory, a reaction occurs when reactant particles collide with sufficient energy and the correct orientation.
3. Consider the effect of increasing the concentration of reactants. When the concentration is higher, there are more particles available to collide with each other. This increases the likelihood of collisions occurring more frequently.
4. Therefore, by logically connecting the concepts of concentration, collision theory, and the frequency of collisions, you can conclude that a higher concentration increases the rate of reaction.