Predict the reagent or the product in the followig reaction sequence.

Explanation

(i) Since the reagnet (1) reduces `-NO_(2)` to `-NH_(2)`, therefore, reagent (1) is either Sn/HCl or Fe/HCl.
(ii) Since p-methylacetanilide on treatment with a mixture of conc. `HNO_(3)+conc.H_(2)SO_(4)` gives compound (2) therefore, compound (2) must be , 2-nitro-4-methylacetanilide.
(iii) since reagent (3) brings about hydrolysis of `NHCOCH_(3)` to `NH_(2)`, therefore, it must be an aqueous acid, i.e., `H^(+)//H_(2)O`
(iv) Since product (4) is obtained upon treatment of `1^(@)` aromatic amine with `NaNO_(2)//HCl`, therefore, compound (4) must be a diazonium salt, i.e.,
2-Nitro-4-methylbenzenediazonium chloride.
(v) since reagent (5) brings about the substitution of diazo `(N_(2)^(+))` group by H or brings about reduction of diazonium chloride, therefore, it must be aqueous hypophoshorus acid, i.e. `H_(3)PO_(2)//H_(2)O`.