Choose the correct statement for chemical adsorption.

Regarding the adsorption of a gas on the surface of a solid,which of the following is $NOT$ true?

$A$ particular adsorption process has the following characteristics: $(i)$ It arises due to van der Waals forces and $(ii)$ it is reversible. Identify the correct statement that describes the above adsorption process.

Adsorption is multilayer in case of

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 $(N_A) = 6.0 \times 10^{23} \ mol^{-1}$]

Adsorption is accompanied by