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. Indicate any pairs of ions which on testing as above leads to the observed changes.

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. Indicate any pairs of ions which on testing as above leads to the observed changes.
Answer» `AI^(3+)` and `MN^(2+)` ions `MG^(2+)` and `ZN^(2+)` ions `Mn^(2+)` and `Mg^(2+)` ions `Zn^(2+)` and `Mn^(2+)` ions Answer :A