First premise: Reactants must collide in order to react and form products. A 2 + B 2 2 AB Collision Theory

First premise: Reactants must collide in order to react and form products. A 2 + B 2 2 AB Second premise: Reactants must have the correct orientation to form the products upon collision

Collision Theory First premise: Reactants must collide in order to react and form products. A 2 + B 2 2 AB Second premise: Reactants must have the correct orientation to form the products upon collision Third premise: Reactants must have sufficient energy for the collision to result in formation of products E < E a

Collision Theory First premise: Reactants must collide in order to react and form products. A 2 + B 2 2 AB Second premise: Reactants must have the correct orientation to form the products upon collision Third premise: Reactants must have sufficient energy for the collision to result in formation of products E > E a

Reaction progress Energy EaEa Activated complex: an unstable transition state between reactants and products. It can either fall back down on the reactant side or go on to the product side.  H rxn

Reaction progress Energy EaEa  H rxn EaEa A catalyst speeds up the rate of a reaction by lowering the activation barrier

Reaction progress Energy  H rxn EaEa A catalyst speeds up the rate of a reaction by lowering the activation barrier