The electronic configuration of elements $\mathrm{A}, \mathrm{B} \& \mathrm{C}$ are $\left[\mathrm{H}\mathrm{e}\right] 2{\mathrm{s}}^1,\mathrm{ }\left[\mathrm{N}\mathrm{e}\right] 3{\mathrm{s}}^1$ & $\left[\mathrm{A}\mathrm{r}\right] 4{\mathrm{s}}^1$ respectively. Which one of the following order is correct for the first ionization potentials (in $\mathrm{KJm}\mathrm{o}{\mathrm{l}}^{–1}$) of $\mathrm{A}, \mathrm{B} \& \mathrm{C}$?

Give a reason for the following:

Inert gases do not form ions.

Given below are two statements: One is labelled as Assertion A and the other is labelled as Reason R.

Assertion A: Amongst $\mathrm{He}, \mathrm{Ne}, \mathrm{Ar}$ and $\mathrm{Kr}$; $1 \mathrm{g}$ of activated charcoal adsorbs more of $\mathrm{Kr}$.

Reason R: The critical volume ${\mathrm{V}}_{\mathrm{c}} ({\mathrm{cm}}^3 {\mathrm{mol}}^{–1})$ and critical pressure ${\mathrm{P}}_{\mathrm{c}}$ (atm) is highest for Krypton but the compressibility factor at critical point ${\mathrm{Z}}_{\mathrm{c}}$ is lowest for Krypton.

In the light of the above statements, choose the correct answer from the options given below.

The following table represents the elements and the atomic number. With reference to this, answer the following using only the alphabets given in the table.

Which element has an electron affinity zero?

Account for the following:

Boiling point of noble gases increases from $\mathrm{He}$ to $\mathrm{Rn}$.

Answer the following :

Noble gases have very low boiling points. Why?

Noble gases are named because of their inertness towards reactivity. Identify an incorrect statement about them.