Chapter 3, Problem 3.58SP

Interpretation Introduction

Interpretation:

The two elements in first row of transition metal with four unpaired electrons in their $2+$ ions haveto be identified.

Concept introduction:

By using aufbau principle, electrons starts to occupy from orbitals oflower energy level. Thus, the obtained lower energy configuration is known as ground-state electron configuration.

Aufbau principle:

• Electrons first occupy orbitals with lower energy than higher energy.
• An orbital can be occupied only by two electrons having opposite spins.
• Each electron fills each orbital till it is half filled, when they are degenerate orbital. This is called as Hund’s rule.
• The order of electrons filling in an atom is given as

Figure 1