Home > Subjects > Chemistry > Level 2 > 2.7 Oxidation–reduction > Subject content
- Subject: Chemistry
- AS: AS90311
- Level: 2
- Credits: 3
- External
Chemistry 2.7 Describe oxidation–reduction reactions
Subject content
Make sure you have up-to-date course notes. You need to understand the following:
- Knowledge of appearance and state of the following reactants and their products:
- oxidants – limited to O2, I2, Cl2, Fe3+, H2O2, MnO4-(aq)/H+, Cr2O72-(aq)/H+
- reductants – limited to metals, C, CO, H2, Fe2+, Br-, I-, SO2,
(HSO3-).
Appropriate information relating to any other oxidants and reactants will be provided.
- Aspects of oxidation-reduction include:
- Determine oxidation numbers.
- Write balanced oxidation–reduction equations.
- Identify the oxidant and/or reductant from a given reaction.
- Recognise the ability of halogens to act as oxidants in reactions with other elements, water, or halide ions.
- Principles of simple electrolytic cells. An electrolytic cell is a type of electrochemical cell where electrical energy is used to drive an oxidation-reduction reaction in a direction that does not occur spontaneously. This is called electrolysis. The link explains the principles behind electrolytic cells.
Note that knowledge of preferential discharge, where one ion has a greater tendency to be discharged during electrolysis before another ion, is not required.
Sit back and view an animated introduction to Oxidation and reduction (redox).
There is a good summary for NCEA level 2, with interactive exercises, at Internet chemistry – oxidation-reduction and interesting applications of oxidation-reduction reactions to everyday life.
