When sodium fusion extract of an organic compound is boiled with iron$(II)$ sulphate solution followed by addition of concentrated $H_2SO_4$,it gives a Prussian blue colour. This confirms the presence of which element?

Given below are two statements :
Statement $I :$ In Lassaigne's test,the covalent organic molecules are transformed into ionic compounds.
Statement $II :$ The sodium fusion extract of an organic compound having $N$ and $S$ gives prussian blue colour with $FeSO_4$ and $FeCl_3$.
In the light of the above statements,choose the correct answer from the options given below.

Match the organic compounds in column $I$ with the Lassaigne's test results in column $II$ appropriately.

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 $FeSO_4$

Discuss the chemistry of Lassaigne's test.

Which of the following nitrogen-containing compounds does not give Lassaigne's test?

Match Column $-I$ with Column $-II$.

Column $-I$	Column $-II$
$(A).$ Dumas method	$(3).$ Nitrogen gas
$(B).$ Kjeldahl's method	$(5).$ Ammonium sulphate
$(C).$ Carius method	$(1).$ $AgNO_3$
$(D).$ Chromatography	$(2).$ Silica gel
$(E).$ Homolytic fission	$(4).$ Free radical