The order of ionisation potential between $He^{+}$ ion and $H$ atom (both species are in gaseous state) is

Which of the following configurations represents atoms of the elements having the highest second ionization energy?

Identify the elements $X$ and $Y$ using the ionisation energy values given below :

Element	Ionization energy $1^{st}$ $(kJ/mol)$	Ionization energy $2^{nd}$ $(kJ/mol)$
$X$	$495$	$4563$
$Y$	$731$	$1450$

Given below are two statements:
Statement $I$: The second ionization enthalpy of $B$, $Al$ and $Ga$ is in the order of $B > Al > Ga$.
Statement $II$: The correct order in terms of first ionization enthalpy is $Si < Ge < Pb < Sn$.

$A \to A^{+} + e, E_{1}$ and $A^{+} \to A^{2+} + e, E_{2}$. The energy required to pull out the two electrons are $E_{1}$ and $E_{2}$ respectively. The correct relationship between the two energies is:

The first ionization energy (in $kJ / mol$) of $Na, Mg, Al$ and $Si$ respectively,are