Lassaigne's test for nitrogen is negative for | vedclass

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Question

(A) Lassaigne's test is used to detect nitrogen,sulfur,and halogens in organic compounds. In this test,the organic compound is fused with metallic sod

Vedclass · Accepted Answer

$NH_2OH$ (Hydroxylamine)

Vedclass · Answer

(A) Lassaigne's test is used to detect nitrogen,sulfur,and halogens in organic compounds. In this test,the organic compound is fused with metallic sodium $(Na)$. If nitrogen is present,it reacts with sodium to form sodium cyanide $(NaCN)$. However,compounds that do not contain carbon along with nitrogen,or compounds where nitrogen is present in a form that does not easily form $NaCN$ upon fusion,may give a negative result. $NH_2OH$ (Hydroxylamine) does not contain carbon. Since Lassaigne's test requires the formation of $NaCN$ (which requires both $Na$ and $C$),compounds lacking carbon cannot form cyanide ions. Therefore,$NH_2OH$ gives a negative Lassaigne's test for nitrogen.

Column $I$	Column $II$
$A$. Aniline	$i$. Red colour with $FeCl_3$
$B$. Benzene sulfonic acid	$ii$. Violet colour with sodium nitroprusside
$C$. Thiourea	$iii$. Blue colour with hot and acidic solution of $FeSO_4$

Lassaigne's test for nitrogen is negative for which compound?

Similar Questions

Discuss the chemistry of Lassaigne's test.

Assertion : During the test for nitrogen with Lassaigne's extract,on adding $FeCl_3$ solution,sometimes a blood-red coloration is obtained.
Reason : Sulphur is also present along with nitrogen in the organic compound.

Name the methods used for determining the molecular mass of organic compounds.

If on adding $FeCl_3$ solution to acidified Lassaigne solution of an organic compound a blood red colouration is produced,it indicates the presence of

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