If a liquid compound decomposes at its boiling point,which method$(s)$ can you choose for its purification? It is known that the compound is stable at low pressure,steam volatile,and insoluble in water.

Match List-$I$ with List-$II$.

List-$I$ (Purification technique)	List-$II$ (Used to separate)
$A$. Simple distillation	$I$. Steam volatile compound
$B$. Fractional distillation	$II$. Two liquids with large difference in boiling points
$C$. Steam distillation	$III$. Liquid decomposing at its boiling point
$D$. Distillation under reduced pressure	$IV$. Two liquids with close boiling points

Explain why an organic liquid vaporizes at a temperature below its boiling point during steam distillation.

What is an eluant?

The method used for the separation of the mixture of products ($B$ and $C$) obtained in the following reaction is:

Give the answer of the following questions in short:
$(i)$ When is simple distillation used?
$(ii)$ When is fractional distillation used?
$(iii)$ Which liquid is obtained first in fractional distillation?
$(iv)$ Which liquid is cooled first in fractional distillation?
$(v)$ What happens in the fractional column?