Which of the following transitions involves the maximum amount of energy?

Outermost electronic configurations of four elements $A, B, C, D$ are given below:
$A: 3s^{2}$
$B: 3s^{2} 3p^{1}$
$C: 3s^{2} 3p^{3}$
$D: 3s^{2} 3p^{4}$
The correct order of first ionization enthalpy for them is:

The $1^{\text{st}}$,$2^{\text{nd}}$,and $3^{\text{rd}}$ ionization enthalpies $I_1, I_2$,and $I_3$ of four atoms with atomic numbers $n, n+1, n+2$,and $n+3$,where $n < 10$,are tabulated below. What is the value of $n$?

Atomic number	$I_1$ $(kJ/mol)$	$I_2$ $(kJ/mol)$	$I_3$ $(kJ/mol)$
$n$	$I_1$	$I_2$	$I_3$
$n+1$	$1681$	$3374$	$6050$
$n+2$	$2081$	$3952$	$6122$
$n+3$	$496$	$4562$	$6910$
$n+4$	$738$	$1451$	$7733$

The second ionisation potential of an element $M$ is the energy required to

Which of the following statements is incorrect?

The element having the greatest difference between its first and second ionization energies is: