Starting from the $1^{st}$,the successive ionization potentials of an element are respectively $5.98, 18.8, 28.4, 120.1, 154 \ eV$. The element is

The set representing the correct order of first ionisation potential is

The first ionization enthalpy of the following elements are in the order:

What is the correct order of the first ionization energy for $Li, Be, B,$ and $Na$?

From the ground state electronic configuration of the elements given below,pick up the one with the highest value of second ionization energy.

Electronic configurations of four elements $A$,$B$,$C$,$D$ are given below:
$A$) $1s^2 2s^2 2p^6 3s^1$
$B$) $1s^2 2s^2 2p^6 3s^2 3p^1$
$C$) $1s^2 2s^2 2p^6 3s^2$
$D$) $1s^2 2s^2 2p^6 3s^2 3p^2$
The correct order of first ionization enthalpy of these elements is: