Correct Answer - 3
Both dissolves inacids.` Cr(OH)_(3)` is partially soluble whiel `Fe(OH)_(3)` is not soluble in aqueous `NH_(3)`. Only `Cr(OH)_(3)` not `Fe(OH)_(3)` in soluble by `NaOH//H_(2)O_(2)` according to the reaction.
`Cr(OH)_(3)darr("green")overset(NaOH//H_(2)O_(2))rarrCrO_(4)^(2-)("yellow solution")+H_(2)O`.
