The violet colour obtained during the test of sulphur by lassaigne's test is due to the formation of
1) \(Na_{2}[Fe(CN)_{5}S]\)
2) \(Na_{2}[Fe(CN)_{6}\)]
3) \(Na_{2}[Fe(CN)_{5}\)NO
4) \(Na_{4}[Fe(CN)_{5}NOS]\)

During detection of sulphur is lassign's test a violet compound with formula Na_(x)[Fe(CN)_(5)NOS is formed. What is "x"?

In the Lassaigne’s test for nitrogen in an organic compound, the Prussian blue colour is obtained due to the formation of: (a) Na_(4)[Fe(CN)_(6)] (b) Fe_(4)[Fe(CN)_(6)]_(3) (c) Fe_(2)[Fe(CN)_(6)] (d) Fe_(3)[Fe(CN)_(6)]_(4)

Fe(CN)_(2)darr+4KCN to K_(4)[Fe(CN)_(6)]

The violet-red colour in the Lassaigne’s test of sulphur is due to S^(2-) + underset("Sodium nitro prusside")([Fe(CN)_(5)(NO)]^(2+)) to (3)

In K_4[Fe(CN)_6]Fe is in the form of