Using the provided information in the following paper chromatogram,calculate the $R_{f}$ value of $A$ .......... $\times 10^{-1}$.

The boiling point of aniline is $457 \ K$. At which temperature does aniline boil in simple distillation and in steam distillation?

Which of the following statements about $TLC$ are correct?
$(i)$ Glycine is identified on $TLC$ plate due to its colour.
$(ii)$ Amino acids can be detected by spraying the $TLC$ plate with $Ninhydrin$ solution.
$(iii)$ The retardation factor $(R_f)$ is the ratio of the distance travelled by the solute to that of the solvent from the base line.
$(iv)$ Sodium chloride is commonly used as an adsorbent.

How do you perform the purification of the following?
$(i)$ The boiling point of liquid $X$ is $450 \ K$ and it decomposes at $400 \ K$ temperature.
$(ii)$ Mixture of $60 \% \ \text{Camphor}$ and $40 \% \ BaSO_4$.

What is chromatography used for?

The principle of column chromatography is