When an electron is added to elements of group $16$ and $17$ in $n = 2$ and $n = 3$ shells,which case experiences less electron-electron repulsion and why?

Which element has maximum electron affinity?

Nitrogen has lower electron affinity than its preceding element carbon because

The correct order of the electron gain enthalpy of the given elements is

Given below are two statements:
Statement $I$: Fluorine has most negative electron gain enthalpy in its group.
Statement $II$: Oxygen has least negative electron gain enthalpy in its group.
In the light of the above statements,choose the most appropriate from the options given below.

The electron gain enthalpy $\Delta_{eg}H$ of $Cl_{(g)}$ is $-349 \ kJ \ mol^{-1}$. If the ground state energy of $Cl_{(g)}$ is $x \ kJ \ mol^{-1}$,the ground state energy (in $kJ \ mol^{-1}$) of $Cl^{-}_{(g)}$ is