Question 6.4: Higher Ionization Energies Which has the larger fifth ioniza...

Ge: [Ar] 4s^{2}  3d^{10} 4p^{2}                        As: [Ar] 4s^{2} 3d^{10} 4p^{3}

The group 4A element germanium has four valence-shell electrons and thus has four relatively low ionization energies, whereas the group 5A element arsenic has five valence-shell electrons and has five low ionization energies. Germanium has a larger E_{i5} than arsenic because the fifth electron to be removed in Ge occupies a lower electron shell (n = 3).