Which one of the following is present in gas mask?

Freundlich adsorption isotherms for the physical adsorption of a gas at temperatures $T_1$,$T_2$ and $T_3$ are shown in the graph given below. The correct relationship between $T_1$,$T_2$ and $T_3$ is:

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

Adsorption is multilayer in case of

The spontaneous adsorption of a gas on the surface of a solid adsorbent is an exothermic process because...

$2.0 \, g$ of $H_2$ gas is adsorbed on $2.5 \, g$ of platinum powder at $300 \, K$ and $1 \, bar$ pressure. The volume of the gas adsorbed per gram of the adsorbent is $..... \, mL$.
(Given: $R = 0.083 \, L \, bar \, K^{-1} \, mol^{-1}$)