Question

In the brown ring test, the brown color of the ring is due to :

• A. a mixture to $NO$ and $N{O}_2$
• B. nitroso ferrous sulphate
• C. ferrous nitrate
• D. ferric nitrate

Answer 1

The correct option is B nitroso ferrous sulphate

In the brown ring test, the brown colour of the ring is due to nitroso ferrous sulphate ( $FeS{O}_4.NO$ ).

Nitric Acid (nitrate) reduces ferrous to ferric and is reduced to nitrogen monoxide ($NO$). This reacts with $FeS{O}_4$ and forms the brown ring.

So, the correct option is $B$