Question

The volume of gases ${{H}_{2}},C{{H}_{4}},C{{O}_{2}}$ and $N{{H}_{3}}$ adsorbed by 1g of charcoal at 288K are in the order:
A.${{H}_{2}} > C{{H}_{4}} > C{{O}_{2}} > N{{H}_{3}}$
B.$C{{H}_{4} }> C{{O}_{2}} > N{{H}_{3}} > {{H}_{2}}$
C.$C{{O}_{2}} > N{{H}_{3}} > {{H}_{2}} > C{{H}_{4}}$
D.$N{{H}_{3}} > C{{O}_{2}} > C{{H}_{4}} > {{H}_{2}}$

Answer 1

Hint: Adsorption is the phenomena where the particles of any gas or liquid accumulate at the surface of any substance rather than at its bulk. The surface on which the species attach is called adsorbate. Charcoal is an adsorbate that is used to keep various gases. The adsorption of gas on a solid depends on the nature of the adsorbate and adsorbent.

Complete answer:
Adsorption is a surface phenomenon when a particle of a gas or a liquid gets attached on the surface of the adsorbent. These particles are called adsorbate. The adsorption depends on many factors one of the factors is the nature of the adsorbent and the adsorbate.
The adsorption of gases on a solid charcoal surface depends on this factor. The nature of the gas affects the intensity of adsorption. A gas that has higher forces of attraction is easily liquefiable. That is converted to a liquid under high pressure.
Among the given gases, ammonia has the highest intermolecular forces of attraction due to hydrogen bonding, so it is easily liquefied and will be adsorbed in more volume on the charcoal.
Also the density of gases define their adsorption, those having higher density per gm will have more adsorption, as $N{{H}_{3}}$ = 181 cc/gm, $C{{O}_{2}}$= 48 cc/gm, $C{{H}_{4}}$= 16 cc/gm and${{H}_{2}}$= 4 cc/gm. Therefore the order of the adsorption of volume in increasing order is $N{{H}_{3}} > C{{O}_{2}} > C{{H}_{4}} > {{H}_{2}}$.

The order of gases adsorbed on the charcoal surface is $N{{H}_{3}} > C{{O}_{2}} > C{{H}_{4}} > {{H}_{2}}$, so option D is correct.

Note:
The unit of density is given in the CGS system that is cubic centimeter per gram. The adsorption of various gases on charcoal is applied in gas masks for workers in industries that are exposed to harmful gases. The masks are lined with charcoal that adsorb the gases like ammonia, methane, etc, but are able to pass oxygen.