Oxidants and reductants

oxidants and reductants

Oxidants, or oxidising agents, are chemical species that oxidise the other chemical species in the chemical reaction. This means that they, in turn, are reduced by the other chemical species.

Reductants, or reducing agents, are chemical species that reduct the other chemical species in the chemical reaction. This, therefore, means that they in turn, are oxidised by the other chemical species.

This has to be the case because in a redox reaction a chemical species is oxidised and loses electrons, whilst another chemical species is reduced, and gains the electrons lost. Remember redox reactions involve a transfer or electrons.

Let's look a some oxidation - reduction reactions, so we can identify the oxidant and reductant.

Some common oxidants and reductants

During many redox reactions observations are apparent that allow for identification of oxidants and reductants. For example looking at the reaction between acidified dichromate and ethanol, above, there is a visible colour change from orange to green. The orange coloured species is the dichromate, which turns green as it is reduced to the chromium ion.

The table below shows some common oxidants and reductants, along with their appearances.

relative strengths of oxidants and reductants

These can be found by looking at a table of Standard Reduction Potentials