Q. Which one of the following reactions does NOT belong to “Lassaigne’s test”?
A) Na + C + N $\xrightarrow{\Delta}$ NaCN
B) 2Na + S $\xrightarrow{\Delta}$ Na$_2$S
C) Na + X $\xrightarrow{\Delta}$ NaX
D) 2CuO + C $\xrightarrow{\Delta}$ 2Cu + CO$_2$
Explanation
[Solution by Claude - not from source] Lassaigne's fusion forms NaCN, $Na_2S$ and NaX. Reduction of CuO by carbon is not part of it. Answer (4).
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.