$X$ and $Y$ have $R_f$ values of $0.75$ and $0.25$ respectively. In column chromatography,which component is obtained first?

Which substance is used in the purification of bone charcoal?

$A$ chromatography column,packed with silica gel as the stationary phase,was used to separate a mixture of compounds consisting of $(A)$ benzanilide,$(B)$ aniline,and $(C)$ acetophenone. When the column is eluted with a mixture of solvents,hexane: ethyl acetate $(20: 80)$,the sequence of obtained compounds is:

By the crystallisation of an impure compound,if the mother liquor becomes coloured,what shall be done to remove the colour?

Three organic compounds $A$,$B$ and $C$ were allowed to run in thin layer chromatography using hexane and gave the following result (see figure). The $R_f$ value of the most polar compound is $............\, \times 10^{-2}$

Which among the following purification methods is based on the principle of "Solubility" in two different solvents?