For a chemical reaction to begin, the reacting molecules must approach and collide. The bonds between the interacting molecules are severed as a result of these collisions, and the product is created with new bonds.
To explain the reaction rates in a gaseous state, Arrhenius presented a simple collision theory. Kinetic molecular theory or reaction rate collision theory is the name given to this theory.
Arrhenius equation is given by where represents the fraction of molecules with an energy equal to or greater than Ea where Ea is the activation energy of reaction, T is temperature, and R is gas constant.
Therefore, signifies the fraction of molecules with an energy equal to or more than the activation energy.