`K_(3)[Fe(CN)_(6)]` is used for the detection of

Options

A. `Fe^(2+)`
B. `Fe^(3+)`
C. `Cd^(2+)`
D. `Cu^(2+)`

Answer

A, B

Explanation

`K_(3)[Fe(CN)_(6)]` or potassium ferricyanide gives dark blue colouration (or ppt.) with `Fe^(2+)` and brown colouration with `Fe^(3+)` . No colour is developed with `Cd^(2+) or Cu^(2+)` ions.