Question

Given below are two statements : one is labelled as
Assertion $A$ and the other is labelled as Reason $R$.
Assertion $A:S{O}_2\left(g\right)$ is adsorbed to a larger extent than $H_2\left(g\right)$ on activated charcoal.
Reason $R:S{O}_2\left(g\right)$ has a higher critical temperature than $H_2\left(g\right)$.
In the light of the above statements, choose the most appropriate answer from the options given below.

• A. $A$ is not correct but $R$ is correct
• B. $A$ is correct but $R$ is not correct
• C. Both $AandR$ are correct but $R$ is not the correct explanation of $A$
• D. Both $A$ and $R$ are correct and $R$ is the correct explanation of $A$

Answer 1

The correct option is D Both $A$ and $R$ are correct and $R$ is the correct explanation of $A$

$S{O}_2$ has higher mass and larger surface area. It has higher critical temperature than $H_2$ and that's why it adsorbed to a larger extent.

Adsorption of gas by charcoal:

Finely divided activated charcoal tends to adsorb several gases like ammonia, sulphur dioxide, chlorine, phosgene, etc. In this case, charcoal acts as an adsorbent while gas molecules act as the adsorbate.
In general, easily liquifable gases such as $C{O}_2,N{H}_3,C{l}_2$ and $S{O}_2$ are adsorbed to a greater extent than the elemental gases like $H_2,O_2,N_2,He$ etc.