Chapter 2, Problem 2.69AP

Interpretation Introduction

Interpretation:

The element should be identified when $\text{1s, 2s, 2p, 3s, 3p, 4s }$ is completely and two electrons in $\text{d-orbital}$ is filled.

Concept introduction:

The periodic table is given below,

Figure 1

The electron configuration is the distribution of electrons of an atom or molecule in atomic or molecular orbitals.

The Aufbau principle:

The aufbau principle is states that in the ground state of an atom, electrons fill atomic orbitals of the lowest available energy levels before occupying higher levels. For example, the 1s shell is filled before the 2s subshell is occupied.

The subshell ordering by this rule is

$\text{1s, 2s, 2p, 3s, 3p, 4s, 3d, 4p, 5s, 4d, 5p, 6s, 4f, 5d, 6p, 7s, 5f, 6d, 7p, 8s, }\mathrm{...}$