A coloured solution known to contain two metal ions of different groups, was treated with excess cold sodium hydroxide solution. When filtered a whitish solid, slowly changing to brown, was retained on the filter paper and a colourless solution collected as the filtrate. Drop wise adition of hydrochloric acid to the filtrate produced a white precipitate which dissolved in excess acid. Treatment of the residue from the filter paper with a strong oxidiser, PbO_(2) and concentratedHNO_(3) on boiling produced a reddish-violet (purple) solution. Reddish-violet (purple) solution is decolourised by:

A coloured solution known to contain two metal ions of different group

1.	A coloured solution known to contain two metal ions of different groups, was treated with excess cold sodium hydroxide solution. When filtered a whitish solid, slowly changing to brown, was retained on the filter paper and a colourless solution collected as the filtrate. Drop wise adition of hydrochloric acid to the filtrate produced a white precipitate which dissolved in excess acid. Treatment of the residue from the filter paper with a strong oxidiser, PbO_(2) and concentratedHNO_(3) on boiling produced a reddish-violet (purple) solution. Reddish-violet (purple) solution is decolourised by:
Answer» both `SO_(3)^(2-),FE^(2+)` both `SO_(4)^(2-),Fe^(3+)` both `NO_(3)^(-),Fe^(2+)` both `H_(2)O_(2),HCO_(3)^(2-)` Answer :A