COMEDK2018ChemistryPractical Chemistry
The brown ring test for nitrates depends on
Options
- Athe reduction of nitrate to nitric oxide
- Boxidation of nitric oxide to nitrogen dioxide
- Creduction of ferrous sulphate to iron
- Doxidising action of sulphuric acid
Correct answer
A. the reduction of nitrate to nitric oxide
Step-by-step solution
The brown ring is appeared due to formation of a brown complex between nitric oxide and Fe ²⁺ ion. This nitric oxide is formed as a result of reduction of nitrate. Brown ring test for nitrates depends on reduction of nitrate to nitric oxide.