Name: ________________________
Periodic Trends Thinking Question
The 1st and 2nd ionization energies (IE) of sodium and magnesium are shown in the table
below. Sodium’s 1st ionization energy is clearly lower than that of magnesium. However,
magnesium’s 2nd ionization energy is considerably lower than that of sodium. On this sheet,
please provide an explanation for this phenomenon and submit for feedback. It may be
helpful to use Bohr-Rutherford diagrams in your explanation.
Na
Mg
1st IE
495.8 kJ/mol
737.7 kJ/mol
2nd IE
4562.4 kJ/mol
1450.6 kJ/mol