Which of the following statements is true regarding chemisorption?

Which one of the following gives a straight line for Freundlich adsorption isotherm?

In an adsorption experiment,a graph between $\log (x/m)$ versus $\log P$ was found to be linear with a slope of $45^\circ$. The intercept on $\log (x/m)$ axis was found to be $0.3010$. The amount of gas adsorbed per gram of charcoal under a pressure of $0.5 \ atm$ is (in $g$)

Given below are the critical temperatures of some of the gases:

Gas	Critical temperature $(K)$
$He$	$5.2$
$CH_{4}$	$190$
$CO_{2}$	$304.2$
$NH_{3}$	$405.5$

The gas showing least adsorption on a definite amount of charcoal is:

For a gas-solid adsorbent system,the adsorption isotherm $\frac{x}{m}=k p^{1/n}$ is applicable,where $n=5$ in the specified case. Point out the correct statement:

Which of the following statements regarding adsorption is incorrect?