When the $TLC$ solvent reaches a height of $10 \, cm$,compound $(A)$ reaches $8 \, cm$ and compound $(B)$ reaches $6 \, cm$. Calculate the $R_f$ values of $(A)$ and $(B)$.

In thin layer chromatography,a substance moved by a distance of $4 \ cm$,whereas the solvent moved by a distance of $5 \ cm$. Then the value of retardation factor $(R_f)$ is

Match List-$I$ with List-$II$:

List-$I$ (Separation of)	List-$II$ (Separation Technique)
$A$. Aniline from aniline$-water$ mixture	$I$. Simple distillation
$B$. Glycerol from spent$-lye$ in soap industry	$II$. Fractional distillation
$C$. Different fractions of crude oil in petroleum industry	$III$. Distillation at reduced pressure
$D$. Chloroform$-Aniline$ mixture	$IV$. Steam distillation

Choose the correct answer from the options given below:

$A$ liquid with a high boiling point decomposes on simple distillation,but it can be steam distilled for its purification. Explain how this is possible.

Fill in the blanks:
$1$. In differential extraction from two layers,the .......... layer is above because .............
$2$. The organic solvent used in differential extraction is .......... in water.
$3$. If an organic compound is ......... soluble in an organic solvent,then the continuous extraction technique is used.
$4$. ........ solution is added to produce the precipitate of halide for the estimation of halogen.

Which technique is used for the separation of a compound present in an aqueous solution?