Question

What happened with enthalpy of ionization when increase in atomic size?

Answer 1

Size of the atom:

Ionization enthalpy lessens as the atomic size gets higher.

As the distance of the outer electrons from the nucleus increases with increase the atomic radius, the attractive force on the outer electrons decreases.

Accordingly, outer electrons are held less firmly and for this reason, a lesser amount of energy is required to knock them out.

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