What effect does concentration have on the rate of a chemical reaction?
For most reaction involving liquid and gas, doing so will usually increase the chemical reaction.
As a solution is more concentrated, there are more atoms moving around. Hence, it's atoms have a higher chance of colliding with the reactant particles causing the reaction to occur faster.
Typically, increasing the concentration of one or both of your reagents will increase the rate of reaction.
Rates of reaction is often governed by collision theory. Particles are always moving around with a certain energy. Reagent particles react by colliding with a combined energy which is greater than the activation energy of the reaction. This is called a successful collision.
Concentration in this context is a measure of the number of particles occupying a certain volume. Increasing the concentration means there are more particles in the same volume.
More particles in the same volume means that there is a greater chance of collisions occurring between particles. As there are more collisions, the chances of a successful collision also increase. Therefore, more reactions happen more quickly, so the rate of reaction is greater.