When compound (A) is treated with conc. `H_(2)SO_(4)`, a reddish brown colour gas (B) is evol  :
Channel: Doubtnut
Date: 12/04/2020

When compound (A) is treated with conc. `H_(2)SO_(4)`, a reddish brown colour gas (B) is evolved. To this solution, a solution of (C ) is added slowly from the side of the test tube, a blue ring is obtained at the junction of two layers due to formation of (D).   Compound (D) has formula :