Question

What happens when ionization energy increases?

Answer 1

Ionization energy:

The energy which is required to remove the high-energy electrons from a neutral atom which is increases when it goes in increasing order of period and decreases when it goes towards the increasing order of group in a periodic table.

Causes to increase in ionization energy when moving from period 1 to 7 (left to right):

1. The atomic number increase which shows the increase in the number of protons and electrons. The tendency of positive charge on the nucleus is due to a strong attractive force between the nucleus and the outermost electrons which is difficult to separate them so that there is an increase in the ionization energy.
2. As the movement from left to right in a periodic table then the atomic size decreases due to the decrease in atomic radii due to which there is an increase in ionization energy.

Causes an increase in ionization energy when moving from group 18 to 1 (bottom to top):

1. The nuclear charge decreases due to the decrease in the number of protons so the shielding effect occurs by the electrons due to a decrease in the inner shells.
2. High energy is required to remove the valence electrons.