Which of the following will not liberate nitrogen gas on treatment with `HNO_(2)` at `0.^(@)C` ?

Options

A. Benzylamine
B. Urea
C. Aniline
D. Benzamide

Answer

C

Explanation

Aniline (and all other primary aromatic monoamines) forms diazonium salt which are stable in cold aqueous solution :
`C_(6)H_(5)NH_(2)+HNO_(2)+HCIrarr underset("Benzenediazonium chloride")(C_(6)H_(5)H_(2)^(+)Cl^(bar)+2H_(2)O)`
Both benzamide and benzylamine react with nitrous acid to evolve `N_(2)` gas quantitatively
`C_(6)H_(5)CONH_(2)underset(HCI)overset(NaNO_(2))rarrN_(2)`
`C_(6)H_(5)CH_(2)NH_(2) underset(HCI)overset(NaNO_(2))rarrN_(2)`
However nitrogen is not evolved quantitatively when nitrous acid reacts with urea
`CO(NH_(2))_(2)+2HNO_(2)rarrCO_(2)+3H_(2)O+2N_(2)`
Nitrogen is also evolved (again not quantitatively) when urea is reacted with excess of alkaline hypobromite
.