(a) What factors determine whether a collision between two molecules will lead to a chemical reaction? (b) Does the rate constant for a reaction generally increase or decrease with an increase in reaction temperature? (c) Which factor is most sensitive to changes in temperature-the frequency of collisions, the orientation factor, or the fraction of molecules with energy greater than the activation energy?

(a) The factors determining if a collision between two molecules leads to a chemical reaction are: 1. Energy – the molecules must have enough kinetic energy to overcome the activation energy. 2. Orientation – the molecules must collide in the correct geometry. 3. Steric factors – the molecular structure and size can affect the availability of reactive sites during collision. (b) The rate constant for a reaction, denoted by \(k\), generally increases with an increase in reaction temperature, as described by the Arrhenius equation: \(k = Ae^{(-E_a/RT)}\). (c) Among the three factors, the fraction of molecules with energy greater than the activation energy is the most sensitive to changes in temperature, as higher temperatures significantly increase the number of molecules with sufficient energy to overcome the activation energy barrier.