Describe and explain the effect on the rate of reaction of: (a) changing the concentration of solutions (b) changing the pressure of gases (c) changing the surface area of solids (d) changing the temperature (e) adding or removing a catalyst, including enzymes using collision theory

Explain how oxides of nitrogen form in car engines and describe their removal by catalytic converters, e.g. (2CO + 2NO ightarrow 2CO_2 + N_2)