The Middleton test is used for the detection of which element?

Explain the reason for the fusion of an organic compound with metallic sodium for testing nitrogen,sulphur,and halogens.

Which of the following compounds is not expected to show Lassaigne's test for nitrogen?

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

$A$ solution of $m-$chloroaniline,$m-$chlorophenol and $m-$chlorobenzoic acid in ethyl acetate was extracted initially with a saturated solution of $NaHCO_3$ to give fraction $A$. The left over organic phase was extracted with dilute $NaOH$ solution to give fraction $B$. The final organic layer was labelled as fraction $C$. Fractions $A$,$B$ and $C$ contain respectively

Sodium fusion extract of aniline,when heated with ferrous sulphate solution and then acidified with concentrated $H_2SO_4$,forms which of the following complexes?