The central idea of the collision model is that molecules must collide in order to react. Give two reasons why not all collisions of reactant molecules result in product formation.

One reason why not all collisions of reactant molecules result in product formation is due to insufficient collision energy. When two molecules collide, they need to possess a minimum amount of energy, known as the activation energy, to break the existing chemical bonds and form new ones. If the colliding molecules do not have enough energy to overcome this activation energy barrier, the reaction will not occur, and the molecules will simply bounce off each other without any chemical change.

Another reason why not all collisions result in product formation is the inappropriate collision geometry. For a chemical reaction to occur, the reactant molecules must collide with the correct orientation, allowing the reacting atoms to come into contact upon colliding. If the molecules collide with an incorrect orientation, the reaction will not take place, even if the collision energy is greater than the activation energy. This is because the necessary bonds cannot be broken and new bonds cannot be formed due to the misalignment of the reacting atoms. In conclusion, not all collisions between reactant molecules result in product formation due to two primary reasons: insufficient collision energy and inappropriate collision geometry. Understanding these factors is essential for comprehending the collision model as well as predicting and controlling the rates of chemical reactions.