Which of two : Na or Mg has higher second ionisation enthalpy?

Which of the following has highest ionisation enthalpy? P , N , As , Sb .

The first ionisation enthalpy of nitrogen is higher than that of oxygen but the second ionisation enthalpy is higher in oxygen than that of nitrogen. Explain

The correct order of decreasing second ionisation enthalpy of Ti (22), V (23), Cr (24) and Mn (25)

Which has higher ionisation enthalpy and why, Mg or Al.

Among Be, B and C, which element has the highest first ionisation enthalpy and why ?

In a period from Li to F ionisation enthalpy

How would you explain the fact that the first ionization enthalpy of sodium is lower than that of magnesium but its second ionization enthalpy is higher than that of magnesium ?

Give reasons for the following: Chlorine has higher electron gain enthalpy than fluorine.