Revision of Oxidation and Reduction

Revision of oxidation and reduction

You should remember the terms oxidation and reduction from Grade 11:

• \(\color{blue}{\textbf{Oxidation}}\) involves a loss of electrons

• \(\color{red}{\textbf{Reduction}}\) involves a gain of electrons.

An easy way to remember this is:

In both oxidation and reduction a transfer of electrons is involved resulting in a change in the oxidation state of the elements.

• An element or compound that loses electrons is \(\color{blue}{\textbf{oxidised}}\).

  e.g. \(\color{blue}{\textbf{Zn(s)} \to {\textbf{Zn}}^{\textbf{2+}}\textbf{(aq) + 2e}^{\textbf{-}}}\)

  As it loses electrons it gives them away to another element or compound and the element or compound it gives the electrons to is \(\color{red}{\textbf{reduced}}\).

  This makes the compound or element which loses electrons a \(\color{blue}{\textbf{reducing agent}}\).

• An element or compound that gains electrons is \(\color{red}{\textbf{reduced}}\).

  e.g. \(\color{red}{\textbf{Cu}^{\textbf{2+}}{\textbf{(aq) + 2e}}^{\textbf{-}} \to \textbf{Cu(s)}}\)

  As it gains electrons it takes them away from another element or compound and the element or compound it takes them from is \(\color{blue}{\textbf{oxidised}}\).

  This makes the compound or element which gains electrons an \(\color{red}{\textbf{oxidising agent}}\).