Which of the following gases is adsorbed to the maximum extent by activated charcoal?

Froth floatation process for concentration of ores is an illustration of the practical application of:

Arrange the gases $H_2, CH_4, CO_2,$ and $NH_3$ in the order of their volume adsorbed on $1 \ g$ of charcoal at $288 \ K$.

In the adsorption of acetic acid on activated charcoal,the acetic acid is an

Adsorption of a gas on a solid adsorbent follows the Freundlich adsorption isotherm. If $x$ is the mass of the gas adsorbed on mass '$m$' of the adsorbent at pressure $p$, then from the given graph, the extent of adsorption is proportional to:

The mass of gas adsorbed,$x$,per unit mass of adsorbent,$m$,was measured at various pressures,$p$. $A$ graph between $\log(x/m)$ and $\log p$ gives a straight line with slope equal to $2$ and the intercept equal to $0.4771$. The value of $x/m$ at a pressure of $4 \text{ atm}$ is: (Given $\log 3 = 0.4771$)