question_answer

The prussian blue colour obtained in the Lassaigne's test for nitrogen is due to the formation of

A) Iron (II) hexacyanoferrate (III)

B) Iron (III) hexacyanoferrate (II)

C) Iron (III) hexacyanoferrate (III)

D) Iron (II) hexacyanoferrate (II)

Correct Answer: B

Solution :

The chemistry of the Lassaigne's test of nitrogen is \[2NaCN + FeS{{O}_{4}} \xrightarrow{{}}\,\,Fe{{\left( CN \right)}_{2}} + N{{a}_{2}}S{{O}_{4}}\]