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

How would you explain the fact that the first ionization enthpy of sod

1.	How would you explain the fact that the first ionization enthpy of sodium is lower than that of magnesium but its second ionization enthalpy is higher?
Answer» As Na has 11 electrons , and its valence shell has 1 electron in 3s orbital. So that 1 electron can be easily removed as it is unpaired. Then it attains a noble gas state. Next , if we want to remove another electron , we should give more energy to remove an electron as they are in noble gas state. Hence, the SECOND IE is GREATER. Whereas in case of MG , 2 electrons are there in its valence shell. So it’s IE is LOWER.