Chemistry · Practical Organic Chemistry

NEET (UG) 2025 — Question 83

Which one of the following reactions does NOT belong to "Lassaigne's test" ?

Option A:
$\mathrm{Na}+\mathrm{C}+\mathrm{N} \xrightarrow[\Delta]{ } \mathrm{NaCN}$
Option B:
$2 \mathrm{Na}+\mathrm{S} \longrightarrow \mathrm{Na}_{2} \mathrm{~S}$
Option C:
$\mathrm{Na}+\mathrm{X} \longrightarrow+\mathrm{NaX}$
Option D:
$2 \mathrm{CuO}+\mathrm{C} \xrightarrow[\Delta]{ } 2 \mathrm{Cu}+\mathrm{CO}_{2}$
Correct

Answer: D

$2 \mathrm{CuO}+\mathrm{C} \xrightarrow[\Delta]{ } 2 \mathrm{Cu}+\mathrm{CO}_{2}$

"Lassaigne's test" is used to detect Nitrogen, Halogen, Sulphur, Phosphorus.

$4^{\text {th }}$ option is detection of carbon, it is not "Lassaigne's test".

Answer key and solution verified before publishing.

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