The technique used for purification of steam volatile water immiscible substances is:

To separate different fractions of crude oil in the petroleum industry,the method used is:

What is column chromatography?

In chromatography,what does $R_f$ stand for?

In the given $TLC$ plate,the distances of spots $A$ and $B$ from the base line are $4 \ cm$ and $6 \ cm$,respectively. The distance moved by the solvent front from the base line is $8 \ cm$. If the $R_f$ value of $B$ is $x \times 10^{-1}$ times that of $A$,find the value of $x$.

Match Column-$I$ and Column-$II$ with the correct relation:

Column-$I$	Column-$II$
$(i)$ Aniline + chloroform	$(p)$ Steam distillation
$(ii)$ Aqueous solution of compound	$(q)$ Fractional distillation
$(iii)$ Mixture of liquids with small difference in boiling point	$(r)$ Differential extraction
$(iv)$ Purification of aniline	$(s)$ Simple distillation