Question

Chemistry of liebermann's nitroso reaction

Answer 1

The test is give by only 2 degree amine(both aliphatic and aromatic). 2 degree amine is converted into nitroso amine by treating the amine with HNO2.On warming the phenol and conc. H2SO4 brown red colour is formed at first, which changes to blue then green.colour changes to red on dilution and further to greenish blue or violet on treatment with alkali.

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