The first ionization energy, generally: A) is inversely proportional to the square of Z_eff and increases from left to right in the period. B) is directly proportional to the square of Z_eff and increases from left to right in the period C) is directly proportional to the square of Z_eff and increases from down a group.

Question

Quizplus · Accepted Answer

The first ionization energy is directly proportional to the effective nuclear charge ($Z_{\text{eff}}^2$) because as the effective nuclear charge increases, it becomes more difficult to remove an electron due to the stronger attraction between the nucleus and the electron. Additionally, the first ionization energy generally increases from left to right across a period due to the increase in nuclear charge with the addition of protons, leading to a stronger attraction to electrons and thus higher ionization energy.

The First Ionization Energy, Generally