In Lassaigne's test, the sodium extract of an organic compound containing nitrogen (but no sulphur) is boiled with $FeSO X_{4}$ and then acidified with concentrated $H X_{2} SO X_{4}$ . The colour obtained is

Ablood red
BPrussian blue
Cwhite precipitate
Dviolet

Answer: B

Sodium fusion converts C and N to

NaCN

. With

FeSO X_{4}

this gives hexacyanoferrate(II), which on acidification (Fe(III) formed) gives ferric ferrocyanide, Prussian blue. Blood red colour would need both N and S to be present.

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In Lassaigne's test, the sodium extract of an organic compound containing nitrogen (but no sulphur) is boiled with FeSOX4​ and then acidified with concentrated HX2​SOX4​. The colour obtained is

Answer: B

More questions on Distinguishing tests for functional groups

In Lassaigne's test, the sodium extract of an organic compound containing nitrogen (but no sulphur) is boiled with $FeSO X_{4}$ and then acidified with concentrated $H X_{2} SO X_{4}$ . The colour obtained is