Question

Lassigne's test is used in qualitative analysis to detect

• A. Nitrogen
• B. Sulphur
• C. Chlorine
• D. All of these

Answer 1

Answer: (D)

Nitrogen, sulphur and halogens are tested in an organic compound by Lassaigne's test.
The organic compound is fused with sodium metal as to convert these elements into ionisable inorganic substances,
$Na+C+N\to NaCN$
$2Na+S\to N{a}_{2}S$
$2Na+X_2\to 2NaX$
The cyanide, sulphide or halide ions can be confirmed in aqueous solution by usual test.