Chapter 9, Problem 9D.22E

Interpretation Introduction

Interpretation:

The reason why the copper (II) compounds are colored while copper (I) compounds are colorless has to be explained and also the oxidation number which results in paramagnetic compounds has to be given.

Concept Introduction:

Color of the complex:

According to the crystal field theory, ligands that have high spin are considered weak field and ligands that have low spin are considered strong field.  This relates to the colors seen in a coordination complex.  High spin ligands induce the absorption of longer wavelength (lower frequency=lower energy) light than complexes with low spin ligands since their respective ${\text{Δ}}_{\text{0}}$ values are smaller than the electron pairing energy. If the ions have a noble gas configuration, and have no unpaired electrons, the solutions appear colorless.