Question

Prussian blue is formed when
(a) Ferrous sulphate reacts with FeCl₃
(b) Ferric sulphate reacts with K₄[Fe(CN)₆ ]
(c) Ferrous ammonium sulphate reacts with FeCl₃
(d) Ammonium sulphate reacts with FeCl₃

Answer 1

(b) Ferric sulphate reacts with

$\huge {\bold{ k_{4} [Fe(CN)_{6} ]}}}$

Answer 2

(b) Ferric sulphate reacts with K₄[Fe(CN)₆]

Explanation:

Prussian blue is formed when ferric sulphate reacts with Potassium ferrocyanide as follows:

2Fe2(SO4)3 + 3K₄[Fe(CN)₆] ----> Fe4[Fe(CN)6]3 + 6K2SO4

Fe4[Fe(CN)6]3 is called iron(III) hexacyanoferrate(II). The anion Fe(CN)6 is the Prussian blue.

Option B is the answer.