Which halogen can be oxidised by concentrated nitric acid?
Which halogen can be oxidised by concentrated nitric acid?
Fluorine
Chlorine
Bromine
lodine
Solution
Reducing properties increase from fluorine to iodine, so it is oxidised by nitric acid.
$
\mathrm{I}_2+10 \mathrm{HNO}_3 \longrightarrow 2 \mathrm{HIO}_3+10 \mathrm{NO}_2+4 \mathrm{H}_2 \mathrm{O}
$
Nitric acid oxidises iodine to iodic acid, $\mathrm{HIO}_3$ and not periodic acid $\mathrm{HIO}_4$, which is of a higher oxidation state.
Hence, option (4) is the correct