Activation energy is the minimum energy needed for ‘successful collisions’ where atoms within the reactants rearrange to form products. It can be represented on an energy level diagram.

In the course of work on the kinetics of this solid state reaction, the problem arose of deducing the reaction constant and the activation energy without exact knowledge of the reaction mechanism ...

A reaction profile includes the activation energy, which is the minimum energy needed by particles when they collide for a reaction to occur. The activation energy is shown as a 'hump' in the line ...