TS EAMCET 19-July-2022 Shift 1 Solved Paper

The test for nitrate ion is called "brown ring test". It can be performed by adding FeSO4 to a solution of nitrate followed by careful addition of conc. H2SO4 along the sides of test tube. In this reaction, NO (nitric oxide) is formed in situ which then reacts with the iron (II) complex to give brown ring along the sides of test tube.
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