Collision Theory & Activation Energy

• Collision theory explains how various factors affect rates of reactions
• According to this theory, chemical reactions occur only when reacting particles collide with each other and with sufficient energy
• The minimum amount of energy that particles have to have to react is called activation energy
• Increasing the concentration of reactants in solution, the pressure of reacting gases, and the surface area of solid reactants increases the frequency of collisions and so increases the rate of reaction