How would you detect sulphur?

1.	How would you detect sulphur?
Answer» Solution :(i) To a portion of the Lassaigne.s extract, freshly prepared sodium nitroprusside solution is added. If deep violet or purple colour is formed, the presence of sulphur is confirmed. `UNDERSET("Lassaigne.s extract")(Na_(2)S) + underset("Sodium nitro-prusside")(Na_(2)[Fe(CN)_(5) NO]) rarr underset("Purple colour")(Na_(4)[Fe(CN)_(5)NOS])` (ii) To another portion of Lassaigne.s extract, acetic acid and lead acetate solution are added. If black PRECIPITATE is formed, sulphur presence is confirmed. `underset("Leadacetate")((CH_(3)COO)_(2)Pb) + Na_(2)S rarr underset("Black precipitate")(PbSdarr) + 2CH_(3)COONa`

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