ABSTRACT
Oxidation–reduction (redox) reactions are those involving changes of oxidation states of reactants. Such reactions are easiest to visualize as the transfer of electrons from one species to another. For example, soluble cadmium ion, Cd2+, is removed from wastewater by reaction with metallic iron. The overall reaction is C d 2 + + F e → C d + F e 2 + https://s3-euw1-ap-pe-df-pch-content-public-p.s3.eu-west-1.amazonaws.com/9781315160474/fd82ffd5-5ad6-441c-b2db-b93f95d80b06/content/equ3_1_1.tif"/>
