In brown ring test, which compound is responsible for ring formation?
In brown ring test, which compound is responsible for ring formation?
The correct option is B FeSO4.NO
As ferrous sulphate reacts with nitrous oxide, a compound called nitroso ferrous sulphate FeSO4.NO is formed, which is responsible for brown ring formation.
Brown ring test can be performed by adding Iron(II) sulfate to a solution of a nitrate, then slowly adding concentrated sulfuric acid from the sides of the test tube. The ferrous sulphate layer - being lighter - is at the top whereas sulphuric acid, being heavier, is at the bottom. At the interface of the two liquid layers - there is a temporary brown ring. We have to be careful to add the sulphuric acid slowly as it mixes with water exothermically. The heat released can cause the brown ring to disappear. Also, any disturbance or shake-up can affect the ring formation as well.
FeSO4.NO
As ferrous sulphate reacts with nitrous oxide, a compound called nitroso ferrous sulphate FeSO4.NO is formed, which is responsible for brown ring formation.
Brown ring test can be performed by adding Iron(II) sulfate to a solution of a nitrate, then slowly adding concentrated sulfuric acid from the sides of the test tube. The ferrous sulphate layer - being lighter - is at the top whereas sulphuric acid, being heavier, is at the bottom. At the interface of the two liquid layers - there is a temporary brown ring. We have to be careful to add the sulphuric acid slowly as it mixes with water exothermically. The heat released can cause the brown ring to disappear. Also, any disturbance or shake-up can affect the ring formation as well.
