Freundlich adsorption isotherm gives a straight line on plotting :-

In chromatography,which of the following statements is incorrect for $R_f$?

Adsorption of a gas follows Freundlich adsorption isotherm. If $x$ is the mass of the gas adsorbed on mass $m$ of the adsorbent,the correct plot of $\frac{x}{m}$ versus $p$ is:

The adsorption of a gas on a solid surface follows the Freundlich adsorption isotherm. At $T(K)$,the gas pressure is $2 \ atm$. What is the value of $\frac{x}{m}$? (Given: $n=2$ and $k=$ constant)

Which one of the following graphs represents the Freundlich adsorption isotherm?

Activated charcoal is used to remove colouring matter from pure substances. It works by