question_answer

Phenol\[\xrightarrow[{}]{NaN{{O}_{2}}+conc.{{H}_{2}}S{{O}_{4}}}\]dark colour\[\xrightarrow[{}]{alkali}\]blue colour This reaction is called

A)  Lederer Mannasse reaction

B)  Libermann nitroso reaction

C)  Coupling reaction

D)  Lucas test

Correct Answer: B

Solution :

  This is Libermann's nitroso reaction.