Chapter 19, Problem 96A

Interpretation Introduction

Interpretation: The oxidation state of copper is to be identified based on the color of pottery.

Concept Introduction: Oxidised copper is greenish-blue in color and reduced copper is reddish-brown in color.

Answer to Problem 96A

The state of reduced copper is either +1 or 0. The state of oxidized copper is +2.

Explanation of Solution

  ${\text{Cu}}^{2+}$ ions give a greenish-blue color to the glazing which is oxidized and ${\text{Cu}}^{\text{+}}$ and Cu impart reddish-brown color to the glazing which is reduced. In this way, the oxidation state of copper can be recognized from its color.