Correct for physical adsorption is

To form a complete monolayer of acetic acid on $1 \ g$ of charcoal,$100 \ mL$ of $0.5 \ M$ acetic acid was used. Some of the acetic acid remained unadsorbed. To neutralize the unadsorbed acetic acid,$40 \ mL$ of $1 \ M$ $NaOH$ solution was required. If each molecule of acetic acid occupies $P \times 10^{-23} \ m^2$ surface area on charcoal,the value of $P$ is $\qquad$
[Use given data : Surface area of charcoal $= 1.5 \times 10^2 \ m^2 \ g^{-1}$; Avogadro's number $(N_A) = 6.0 \times 10^{23} \ mol^{-1}$]

Which one of the following characteristics is associated with adsorption?

Which of the following statements is not correct?

The equation which represents the Freundlich adsorption isotherm is ($x = \text{amount of gas}$, $m = \text{mass of solid}$):

According to the Langmuir adsorption isotherm,the amount of gas adsorbed at very high pressures: