describe the following nucleophilic substitution reactions: (a) the reaction with NaOH(aq) and heat to produce an alcohol (b) the reaction with KCN in ethanol and heat to produce a nitrile (c) the reaction with \( NH_3 \) in ethanol heated under pressure to produce an amine (d) the reaction with aqueous silver nitrate in ethanol as a method of identifying the halogen present as exemplified by bromoethane

describe: (a) the complete and incomplete combustion of alkanes (b) the free-radical substitution of alkanes by \( Cl_2 \) or \( Br_2 \) in the presence of ultraviolet light, as exemplified by the reactions of ethane