Chapter 8.3, Problem 8.5BFP

Interpretation Introduction

Interpretation:

The condensed electronic configurations of $\text{Rb}$, $\text{Sr}$ and $\text{Y}$ are to be determined. Also, the element with the highest value of ${\text{IE}}_{\text{2}}$ and ${\text{IE}}_3$ is to be determined.

Concept introduction:

The ionization energy is the amount of energy required to remove the most loosely bound valence electrons from an isolated neutral gaseous atom. It is represented by IE. The amount of energy required to remove one electron from the valence shell of an atom in the gaseous state is called first ionization energy $\left({\text{IE}}_1\right)$. The amount of energy required to remove the second electron from the valence shell of an atom in the gaseous state is called second ionization energy $\left({\text{IE}}_2\right)$ so on.

Its value varies with the ease of removal of the outermost valence electron. If the outermost electron is removed very easily then the value of ionization energy is very small. If the electron is removed with quite a difficulty then the value of ionization energy will be very high.

The ionization energy of an element increases along the period because the electrons are held by high effective nuclear charge. The value of ionization energy decreases down the group because the valence electrons are much farther from the nucleus and therefore experience weaker forces of attraction.