Question

Which Of The Following Compound Does Not Liberate Nitrogen Gas On Treatment With Nitrous Acid?

• A. Carbamide
• B. Alkanamide
• C. Primary amines
• D. Secondary amines

Answer 1

The correct option is D

Secondary amines

Explanation for the correct option:

(D) Secondary amines

• Secondary amines do not react with Nitrous Acid $\left({\mathrm{HNO}}_2\right)$ to liberate Nitrogen gas.
• Only primary amines react with Nitrous acid to liberate Nitrogen gas.
• The chemical reaction can be depicted as:

${\mathrm{R}}_2\mathrm{NH}+\mathrm{H}-\mathrm{O}-\mathrm{N}=\mathrm{O}\left(\mathrm{l}\right)\to {\mathrm{R}}_2\mathrm{N}=\mathrm{O}+{\mathrm{H}}_2\mathrm{O}\left(\mathrm{l}\right)$

Explanation for incorrect options:

(A) Carbamide

• Carbamide which is also known as urea is a primary amine that reacts with Nitrous acid to liberate Nitrogen gas.
• The chemical reaction can be depicted as:

(B) Alkanamide

• Alkanamide is a primary amine that reacts with Nitrous acid to liberate Nitrogen gas.
• For example, Methamide reacts with Nitrous acid to produce Nitrogen gas.
• The chemical reaction can be depicted as:

(C) Primary amines

• Primary amines react with Nitrous acid to liberate Nitrogen gas.
• The chemical reaction can be depicted as:

Hence, the correct option is D i.e. Secondary amines.