You may also want to take a look at one of the sites on smog. After you look at the web start in you text on pages 308-311.
Reactions involve energy changes as chemical bonds are broken and new chemical bonds are formed.
During a reaction the reactants must come in contact with sufficient force and in the correct orientation for reactant bonds to be broken and product bonds to be formed. A rise in temperature can increase the frequency of these collisions and can also increase the force of the collisions. Both will increase the reaction rate. Certain chemicals called catalysts may effect the orientation of molecules and also facilitate the reaction. You will have day 1b to complete this assignment.