Question

How does the ionization enthalpy vary across the periodic table?

Answer 1

Ionization enthalpy:-

• The amount of energy required to remove an electron from an isolated gaseous atom in the ground state is called ionization enthalpy.
• The atomic size increases across the period and decreases down the group due to the increase in the number of shells.
• Due to this, the shielding effect increases, and hence effective nuclear charge decreases.
• The electrostatic pull on the outermost electrons decreases thereby making it easy for them to come out.

Hence, ionization enthalpy increases along the period from left to right and decreases down the group on moving from top to bottom in a periodic table.