What type of reactions have no activation energy?
Known as the “collisional model”, there are three necessary requirements in order for a reaction to take place: 1. the molecules must collide to react. If two molecules simply collide, however, they will not always react; therefore, the occurrence of a collision is not enough. The second requirement is that: 2. there must be enough energy (energy of activation) for the two molecules to react. This is the idea of a transition state; if two slow molecules collide, they might bounce off one another because they do not contain enough energy to reach the energy of activation and overcome the transition state (the highest energy point). Lastly, the third requirement is: 3. the molecules must be orientated with respect to each other correctly. For the reaction to occur between two colliding molecules, they must collide in the correct orientation, and possess a certain, minimum, amount of energy. As the molecules approach each other, their electron clouds repel each other. Overcoming this repu
