4.1.2

Redox Reactions

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Oxidation and Reduction

Oxidation is the gaining of oxygen in a reaction and reduction is the loss of oxygen in a reaction. We can also describe oxidation and reduction in terms of electrons:

Illustrative background for OxidationIllustrative background for Oxidation ?? "content

Oxidation

  • When a substance is oxidised (gains oxygen), it always loses electrons.
Illustrative background for ReductionIllustrative background for Reduction ?? "content

Reduction

  • When a substance is reduced (loses oxygen), it always gains electrons.
Illustrative background for OIL RIGIllustrative background for OIL RIG ?? "content

OIL RIG

  • A useful way of remembering the difference between oxidation and reduction reactions in terms of electrons is 'OIL RIG':
    • Oxidation
    • Is
    • Loss
    • Reduction
    • Is
    • Gain

Oxidation and Reduction

Oxidation and reduction reactions are important types of reactions in chemistry.

Illustrative background for OxidationIllustrative background for Oxidation ?? "content

Oxidation

  • An oxidation reaction involves gaining oxygen.
    • Oxidation reactions can also involve losing electrons.
  • E.g. when metals react with oxygen, metal oxides are produced:
    • Calcium + oxygen → calcium oxide
    • 2Ca + O2 → 2CaO
Illustrative background for ReductionIllustrative background for Reduction ?? "content

Reduction

  • A reduction reaction involves losing oxygen.
    • Reduction reactions can also involve gaining electrons.
  • E.g. when metal oxides lose oxygen and return to their atomic form:
    • Iron oxide + carbon monoxide → iron + carbon dioxide
    • Fe2O3 + 3CO → 2Fe + 3CO2

Jump to other topics

1Atomic Structure

2Chemical Bonding

3Quantitative Chemistry

4Chemical Changes

5Energy Changes

6The Rate & Extent of Chemical Change

7Organic Chemistry

8Chemical Analysis

9Chemistry of the Atmosphere

10Using Resources

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