6D.4 Oxidation-Reduction Reactions
In a complexation reaction, a Lewis base donates a pair of electrons to a Lewis acid.
In an oxidation–reduction reaction, also known as a redox reaction, electrons are
not shared, but are transferred from one reactant to another. As a result of this electron
transfer, some of the elements involved in the reaction undergo a change in oxidation
state. Those species experiencing an increase in their oxidation state are oxidized,
while those experiencing a decrease in their oxidation state are reduced. For
example, in the following redox reaction between Fe3+ and oxalic acid, H2C2O4,
iron is reduced since its oxidation state changes from +3 to +2.