Organic Chemistry Some Basic Principles And Techniques Ques 67
67. Lassaigne’s test is used in qualitative analysis to detect
[1989]
(a) Nitrogen
(b) Sulphur
(c) Chlorine
(d) All of these
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Answer:
Correct Answer: 67.(d)
Solution:
- (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,
$ \begin{aligned} & Na+C+N \longrightarrow NaCN \\ & 2 Na+S \longrightarrow Na_2 S \\ & 2 Na+X_2 \longrightarrow 2 NaX \end{aligned} $
The cyanide, sulphide or halide ions can be confirmed in aqueous solution by usual test.