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)

Describe the formation of covalent bonds in simple molecules, including ( CH_3OH ), ( C_2H_4 ), ( O_2 ), ( CO_2 ) and ( N_2 ). Use dot-and-cross diagrams to show the electronic configurations in these and similar molecules