Which of the following is true of ionization energies as one moves left to right across a period of the periodic table?
A) They consistently decrease.
B) They consistently increase.
C) They generally decrease, but there are some exceptions.
D) They generally increase, but there are some exceptions.

Question

Quizplus · Accepted Answer

Ionization energies generally increase, because the atomic radius decreases and the effective nuclear charge increases as one moves from left to right across a period. However, there are some exceptions where the ionization energy decreases from one element to the next, such as when an electron is being removed from a stable half-filled or fully filled subshell.

Which of the Following Is True of Ionization Energies as One