Identify the gas which is readily adsorbed by activated charcoal.

Wood charcoal is used in gas masks because...

Give a reason why a finely divided substance is more effective as an adsorbent.

Assertion : The relation $\frac{x}{m} = k \cdot p^{1/n}$ is known as Freundlich adsorption isotherm,where $x$ is the mass of gas adsorbed by $m$ grams of adsorbent,$p$ is the equilibrium pressure,$k$ and $n$ are constants for a given system and temperature.
Reason : When several substances have the same value of $\frac{1}{n}$,the lines by which their adsorption isotherms can be represented will meet at a point.

Write any two characteristics of Chemisorption.

Assertion $(A)$: Finely divided charcoal can act as an adsorbent.
Reason $(R)$: Finely divided material has a small surface area.