question_answer

In order to distinguish between\[{{C}_{2}}{{H}_{5}}N{{H}_{2}}\]and \[{{C}_{6}}{{H}_{5}}N{{H}_{2}}\]which of the following reagents is useful?

A)  Hinsberg reagent           

B) \[\beta -\]naphthol

C) \[CC{{l}_{3}}CHO\]                         

D) \[NaOH\]

Correct Answer: B

Solution :

                 \[{{C}_{5}}{{H}_{5}}N{{H}_{2}}\]gives coupling reaction with\[\beta -\]naphthol. \[{{C}_{6}}{{H}_{5}}N{{H}_{2}}\xrightarrow[ice\,cold]{HCl/NaN{{O}_{2}}}\underset{benzene\text{ }diazonium\text{ }chloride}{\mathop{{{C}_{6}}{{H}_{5}}\overset{+}{\mathop{{{N}_{2}}}}\,Cl}}\,\]