Primary alkyl halide `C_(4)H_(9)Br` (a) reacted with alcoholic KOH to give compound (b). Compound (b) is reacted with HBr to give (c ) which is an isomer of (a). When (a) is reacted with sodium metal it gives compound (d), `C_(8)H_(18)` which is different from the compound formed when n-butyl bromide is reacted with sodium. Give the structural formula of (a) and write the equations for all the reactions.

Explanation

The possible structure of (A) are :
`underset((i))(CH_(3)-underset(CH_(3))underset("| ")("C "H-CH_(2)-Br` and `underset((ii))(CH_(3)CH_(2)CH_(2)Br)`
When (A) is reacted with Na, the wurtz reaction takes place.
However it is given that (A) on reaction with Na metal, gives alkane `C_(8)H_(18)` which is not the same as the one obtained from the wurtz reaction of n-butyl bromide. Thus, (A) is not (ii)