Chapter 7.1, Problem 9LC

Interpretation Introduction

Interpretation: To determine the electronic configuration of cadmium cation.

Concept Introduction: The placement of electrons inside orbitals around a nucleus is known as electronic configuration, also known as electronic structure, as well as electron configuration. There are mainly three rules which will apply in the filling of atomic orbitals and they are:

1. Aufbau principle
2. Pauli exclusive principle
3. Hund’s rule

Answer to Problem 9LC

The electronic configuration of ${\text{Cd}}^{\text{2+}}$ will be ${\text{1s}}^{\text{2}}{\text{2s}}^{\text{2}}{\text{2p}}^{\text{6}}{\text{3s}}^{\text{2}}{\text{3p}}^{\text{6}}{\text{4s}}^{\text{2}}{\text{3d}}^{\text{10}}{\text{4p}}^{\text{6}}{\text{4d}}^{\text{10}}$

Explanation of Solution

According to the Aufbau principle, orbitals in the ground state of atoms can be filled in ascending energy order.

• The atomic number of Cd = 48
• By removing two electrons from its outermost shell, the number of electrons = 46
• The electronic configuration of ${\text{Cd}}^{\text{2+}}$ = ${\text{1s}}^{\text{2}}{\text{2s}}^{\text{2}}{\text{2p}}^{\text{6}}{\text{3s}}^{\text{2}}{\text{3p}}^{\text{6}}{\text{4s}}^{\text{2}}{\text{3d}}^{\text{10}}{\text{4p}}^{\text{6}}{\text{4d}}^{\text{10}}$