How the following conversions can be carried out?
(i)Propene to propan-1-ol
(ii)Ethanol to but-1-yne
(iii)1-Bromopropane to 2-bromopropane
(iv)Toluene to benzyl alcohol
(v)Benzene to 4-bromonitrobenzene
(vi)Benzyl alcohol to 2-phenylethanoic acid
(vii)Ethanol to propanenitrile
(viii)Aniline to chlorobenzene
(ix)2-Chlorobutane to 3, 4-dimethylhexane
(x)2-Methyl-1-propene to 2-chloro-2-methylpropane
(xi)Ethyl chloride to propanoic acid
(xii)But-1-ene to n-butyliodide
(xiii)2-Chloropropane to 1-propanol
(xiv)Isopropyl alcohol to iodoform
(xv) Chlorobenzene to p-nitrophenol
(xvi)2-Bromopropane to 1-bromopropane
(xvii)Chloroethane to butane
(xviii)Benzene to diphenyl
(xix)tert-Butyl bromide to isobutyl bromide
(xx) Aniline to phenylisocyanide
(i)
(ii)
(iii)
(iv)
(v)
(vi)
(vii)
(viii)
(ix)
(x)
(xi)
(xii)
(xiii)
(xiv)
(xv)
(xvi)
(xvii)
(xviii)
(xix)
(xx)
A compound (A) with molecular formula $C_4H_9I$ which is a primary alkyl halide, reacts with alcoholic KOH to give compound (B). Compound (B) reacts with HI to give (C) which is an isomer of (A). When (A) reacts with Na metal in the presence of dry ether, it gives a compound (D), C8H18, which is different from the compound formed when n-butyl iodide reacts with sodium. Write the structures of A, (B), (C) and (D) when (A) reacts with alcoholic KOH.