Question

What is the general trend in ionization energy across a row on the periodic table? Using a ground state electron configuration as your basis of comparison, explain Why the ionization energy of boron is less than that of beryllium Why the ionization energy of oxygen is less than that of nitrogen

Answer 1

Ionization energy is defined as the minimum amount of energy required to remove an electron from a neutral atom or molecule( in gaseous phase).

The lower this energy, the more easily the electron can be removed from the atom or molecule to become a cation and vice versa.

The ionization energy increases as we move from left to right across a row in the periodic table. As we move across the table, the no of electrons increase and the bonding between the protons and elctrons increase hence more amount of energy is required to remove the valence electrons as the nuclear charge increases.

Moreover the size of the atoms reduce as the atomic radius decreases. This is due to very tight bonding between the protons and elctrons due to electron shielding. Nuclear charge increases. Hence ionization energy increases across the periodic table.