Why does a higher concentration increase the rate of reaction?
a
It increases the frequency of collisions.
b
It increases the surface area of the particles
c
It decreases the amount of reactants.
d
It lowers the activation energy.
a
It increases the frequency of collisions.
The correct answer is a.
A higher concentration increases the rate of reaction because it increases the frequency of collisions between the reactant particles. When there are more reactant particles in a given volume, there is a higher chance of collisions occurring. The more collisions that happen, the higher the likelihood of successful collisions, resulting in a higher rate of reaction.
The correct answer is a) It increases the frequency of collisions.
When the concentration of reactant molecules is higher, there are more particles in a given volume, and therefore, the chances of them colliding with each other are increased. Since collisions between reactant particles are necessary for a chemical reaction to occur, increasing the concentration leads to more frequent collisions.
To understand why a higher concentration increases the rate of reaction, you can consider the collision theory. According to this theory, for a reaction to occur, reactant particles must collide with each other with sufficient energy and in the correct orientation. By increasing the concentration, the number of reactant particles per unit volume increases, which means there are more opportunities for collisions to happen.
Higher concentrations also lead to an increased chance of effective collisions. An effective collision is one where the reactant particles have enough energy and collide with the correct orientation to result in a reaction. In a solution with a higher concentration, there is a higher likelihood for reactant particles to encounter each other and have effective collisions.
On the other hand, options b, c, and d are incorrect:
- Increasing the surface area of particles (option b) would increase the rate of reaction only in cases where the reaction occurs at the surface of the particles. It does not generally increase the rate of reaction by itself.
- Decreasing the amount of reactants (option c) would likely slow down the reaction rather than increasing its rate since there would be fewer reactant particles available for collisions.
- Lowering the activation energy (option d) would indeed increase the rate of reaction, but concentration does not directly affect the activation energy. Factors such as temperature and catalysts are more commonly associated with altering the activation energy of a reaction.