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Ionization Energy Trends

APCHEM-X7NRJ9

How does the ionization energy of sodium ($Na$) compare to that of potassium ($K$)?

A

The ionization energy of potassium is less than sodium because although there are more protons, potassium has four electron shells compared to sodium, which has three electron shells. This causes an increase in nuclear shielding, requiring less energy to remove the electron.

B

The ionization energy of potassium is more than sodium because there are more protons and one extra electron shell in potassium. This causes an increase in nuclear shielding and requires more energy to remove the electron.

C

The ionization of energy of potassium is less than sodium because there are fewer protons and one less electron subshell. Since there is less attraction, it requires less energy to remove the electron.

D

The ionization energies of both elements are equal because they are of the same group, the alkaline earth metals.