Collision Theory
From Arrhenius equation, it is seen that the rate constant k of a reaction increases with temperature and therefore, the rate of reaction also increases. Why does k depend on temperature? This can be explained, to a certain extent, by collision theory.
According to this theory, a chemical reaction can occur only when reactant molecules collide with energy greater than some minimum value and the collision must occur with proper orientation. This minimum value energy of collision required for two molecules to react is called threshold energy. Collisions with energy greater than this can result in reaction.From collision theory, it is obvious that there are two important barriers to a reaction:
(i) Energy barrier(ii) Orientation barrier.
