Question

Down a group, the ionization energy value generally decreases with ____ effective nuclear charge.

Option 1: Increasing
Option 2: Decreasing
Option 3: No change in
Option 4: Fluctuating

Answer 1

Down a group in the periodic table, ionization energy decreases due to a decreasing effective nuclear charge, as the outer electrons experience less attraction from the nucleus.

Step-by-step explanation:

Down a group in the periodic table, the ionization energy value generally decreases with decreasing effective nuclear charge. This is because as the size of the atom increases down the group, the valence electrons are located further away from the nucleus, experiencing less electrostatic pull. Hence, it becomes easier for an electron to be removed as the attraction from the positive nucleus diminishes. The periodic trend in ionization energy is such that the energy required to remove an electron (ionization energy) decreases down a group and generally increases across a period.