Chapter 8, Problem 8.90P

Interpretation Introduction

Interpretation:

The stability of the lanthanide ions ${\text{Ce}}^{4+}$ and ${\text{Eu}}^{2+}$ with the use of the electronic configurations is to be determined.

Concept introduction:

The electronic configuration of an element tells about the distribution of electrons in the atomic orbitals. It is used to predict the physical, chemical, electrical and magnetic properties of the substance.

The stability of any species is governed by its valence shell configuration. The stability increases if the configuration is half filled or fully filled orbital.

The electrons are filled up in accordance with the following three rules:

1. Aufbau principle which states that the electrons are filled up in the increasing order of their orbitals which follows as: $1s2s2p3s3p4s\text{}3d$.

2. Hund’s rule which states that the pairing of electrons will not start until each of the orbitals is singly occupied.

3. Pauli’s exclusion principle states that no two electrons can have the same value of all the four quantum numbers.