`Fe^(2+)` does not give blue colour with `K_(4)[Fe(CN)_(6)]` but on its reaction with (X) ,blue colour oppears (X) can be

Options

A. `MnO_4^(-)//H^+`
B. `H_2SO_4`
C. `NH_3`
D. All true

Answer

A

Explanation

`MnO_4 H^(+) to[O] : Fe^(2+)overset([O])toFe^(3+)+[Fe(CN)_6]^(4-)to Fe_4[Fe(CN)_6]_3`