In group separation

CHEMISTRY · Single correct · A Level · Chemistry · Reactions of ions in aqueous solution · ICSE

Problem

In group separation, before precipitating out group III metal ions as hydroxides, it is necessary to boil then solution of the salt mixture with a few drops of concentrated HNO3\text{HNO}_3 is treated. This is done to convert: (1) Co2+\text{Co}^{2+} to Co3+\text{Co}^{3+} (2) Fe2+\text{Fe}^{2+} to Fe3+\text{Fe}^{3+} (3) Mn2+\text{Mn}^{2+} to MnO4−\text{MnO}_4^- (4) Cr3+\text{Cr}^{3+} to CrO42−\text{CrO}_4^{2-}

Related theory

Browse the problem library