This Study Mind Tutorial covers the following specification points:

CIE: 1.3.5, 1.3.6, 1.3.7, 1.3.8, 1.3.9,

1.3.5. know that oxidising agents gain electrons

1.3.6. know that reducing agents lose electrons

1.3.7. understand that a disproportionation reaction involves an element in a single species being simultaneously oxidised and reduced

1.3.8. know that oxidation number is a useful concept in terms of the classification of reactions as redox and as disproportionation

1.3.9. be able to indicate the oxidation number of an element in a compound or ion, using a Roman numeral