Question

An organic compound (A) with molecular formula C₆H₇N gives (B) with HNO₂ / HCl at 273K. The aqueous solution of (B) on heating gives compound (C) which gives violet colour with neutral FeCl₃. Identify the compounds A, B and C. Write the equations.

Answer 1

A = C₆H₅NH₂ (aniline);
B = C₆H₂N₂Cl (benzene diazonium chloride)
C = C₆H₅OH (phenol)

(i) Since ‘C’ gives a violet colouration with neutral FeCl₃ it should be phenol.

(ii) Since phenol is obtained by boiling aqueous solution of (B), it should be benzene diazonium chloride.

(iii) Hence, A should be aniline.

Equation: