In the test for Mn^2+ with solid NaBiO3, the solution is acidified with nitric acid and not hydrochloric acid because

Cl- would be oxidised to Cl2 by the oxidant, consuming it and destroying the permanganate colour

HCl is too dilute to dissolve NaBiO3 at any concentration

Cl- would be oxidised to Cl2 by the oxidant, consuming it and destroying the permanganate colour

JEE Main levelSingle correct optionDifficulty 2 of 3qc140

In the test for $Mn X^{2 +}$ with solid $NaBiO X_{3}$ , the solution is acidified with nitric acid and not hydrochloric acid because

A $HCl$ reduces $Mn X^{2 +}$ to $Mn$ metal
B $MnCl X_{2}$ is insoluble in water
C $HCl$ is too dilute to dissolve $NaBiO X_{3}$ at any concentration
D $Cl X^{-}$ would be oxidised to $Cl X_{2}$ by the oxidant, consuming it and destroying the permanganate colour

Bismuthate and permanganate are strong oxidants:

2 Mn X^{2 +} + 5 NaBiO X_{3} + 14 H X^{+} 2 MnO X_{4} X^{-} + 5 Bi X^{3 +} + 5 Na X^{+} + 7 H X_{2} O

. In HCl, chloride is oxidised to chlorine and the purple

MnO X_{4} X^{-}

would be reduced back, so the test fails. Nitric acid is not oxidised.