Which of the following phenomena is exhibited by adsorption?

The following statements relate to the adsorption of gases on a solid surface. Identify the incorrect statement among them.

$2.0 \ g$ of activated charcoal is added to $100 \ mL$ of $0.5 \ M$ acetic acid (molar mass $60 \ g \ mol^{-1}$),shaken well and filtered. The concentration of the solution is reduced to $0.4 \ M$. How many grams of acetic acid is adsorbed on charcoal per gram?

The volumes of gases $H_2, CH_4, CO_2$ and $NH_3$ adsorbed by $1 \ g$ of charcoal at $288 \ K$ are in the order:

Which of the following statements is incorrect?

Adsorption of a gas on an adsorbent follows Freundlich adsorption isotherm. The slope and intercept (on $y$-axis) of the isotherm are $0.5$ and $1.0$ respectively. What is the value of $\frac{x}{m}$,when the pressure of the gas $(p)$ is $100 \ atm$?