Question

Which of the following statement (s) is (are) correct with reference to the ferrous and ferric ions?

(a) Fe³⁺ gives brown colour with potassium ferricyanide 

(b) Fe²⁺ gives blue precipitate with potassium ferricyanide 

(c) Fe³⁺ gives red colour with potassium thiocyanate 

(d) Fe²⁺ gives brown colour with ammonium thiocyanate

Answer 1

The correct option (b) Fe²⁺ gives blue precipitate with potassium ferricyanide 

(c) Fe³⁺ gives red colour with potassium thiocyanate 

Explanation:

The blue, precipitate of Fe²⁺ ions with potassium ferricyanide is due to formation of Turnbull's blue KFe^II [Fe^III (CN)₆].

The red colouration of Fe³⁺ ions with potassium thiocyanate is due to the formation of [Fe(CNS)₃]