Noble gases are adsorbed by

Adsorption is multilayer in case of

Match List-$I$ with List-$II$.

List-$I$	List-$II$
$A$. Physisorption	$I$. Single layer adsorption
$B$. Chemisorption	$II$. $20-40 \, kJ \, mol^{-1}$
$C$. $N_{2(g)} + 3H_{2(g)} \xrightarrow{Fe(s)} 2NH_{3(g)}$	$III$. Chromatography
$D$. Analytical Application of Adsorption	$IV$. Heterogeneous catalysis

Choose the correct answer from the options given below:

What do you understand by activation of adsorbent? How is it achieved?

Assertion : The relation $\frac{x}{m} = k \cdot p^{1/n}$ is known as Freundlich adsorption isotherm,where $x$ is the mass of gas adsorbed by $m$ grams of adsorbent,$p$ is the equilibrium pressure,$k$ and $n$ are constants for a given system and temperature.
Reason : When several substances have the same value of $\frac{1}{n}$,the lines by which their adsorption isotherms can be represented will meet at a point.

What is an adsorption isotherm? Describe Freundlich adsorption isotherm.