Chapter 20, Problem 54E

Interpretation Introduction

Interpretation: An explanation corresponding to the fact that $\text{Co}{\left({\text{NH}}_3\right)}_{\text{6}}{}^{\text{3+}}$ ion is diamagnetic, but $\text{Fe}{\left({\text{H}}_{\text{2}}\text{O}\right)}_{\text{6}}{}^{\text{2+}}$ is paramagnetic is to be stated.

Concept introduction: If a molecule contains unpaired electrons, then, it is said to be paramagnetic, whereas if a molecule does not contain any unpaired electron, then, it is said to be diamagnetic.

Weak field ligand that has small crystal field splitting energy gives high spin due to the presence of maximum unpaired electrons in lower energy ${\text{t}}_{\text{2g}}$ orbitals and higher energy orbitals.

Strong field ligand that has large crystal field splitting energy gives low spin due to the presence of maximum paired electrons in lower energy ${\text{t}}_{\text{2g}}$ orbitals.

To determine: An explanation corresponding to the fact that $\text{Co}{\left({\text{NH}}_3\right)}_{\text{6}}{}^{\text{3+}}$ ion is diamagnetic, but $\text{Fe}{\left({\text{H}}_{\text{2}}\text{O}\right)}_{\text{6}}{}^{\text{2+}}$ is paramagnetic.