The value of activation energy is primarily determined by

Explanation

and rearrangements of atoms involved.(b) Effective collision: Effective collisions provide the minimum energy required for a reaction to proceed, but they don't determine the overall activation energy barrier. The specific energy requirement for a reaction to reach the transition state is dictated by the chemical nature of the reactants and products.(c) Concentration of reactants: Though concentration affects the rate of a reaction, it isn't related to the activation energy's magnitude. Activation energy describes the inherent difficulty of a reaction, independent of the amount of reactants present.Therefore, the activation energy primarily depends on the specific arrangement and properties of the atoms involved in the reactants and products, determining the energy barrier that needs to be overcome for the reaction to occur.