In the detection of nitrogen in an organic compound The appearance of Prussian blue colouration is due to the formation of:
Correct answer: A. Fe4[Fe(CN6)]3
- A. Fe4[Fe(CN6)]3
- B. Na3[Fe(CN)6]
- C. K3[Fe(CN)6]
- D. None
Explanation
In the Lassaigne's test, nitrogen in an organic compound forms sodium cyanide (NaCN) when fused with Na. On adding Fe²⁺ ions, it reacts with CN⁻ to form ferric ferrocyanide (Fe₄[Fe(CN)₆]₃). This compound is Prussian blue, giving the characteristic blue coloration.
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