Metal Oxides (AQA GCSE Combined Science: Trilogy): Revision Note Exam code: 8464

Metal Oxides (AQA GCSE Combined Science: Trilogy): Revision Note

Exam code: 8464

Metal oxides

  • Metals react with oxygen in the air to produce metal oxides

  • Oxidation and reduction involve the addition or removal of oxygen from a substance and are called redox reactions

  • Oxidation is a reaction in which:

    • Oxygen is added to an element or a compound

  • Reduction is a reaction in which:

    • Oxygen is removed from an element or a compound

  • A common example is the reaction with red-brown copper metal to produce black copper oxide:

2Cu + O2 ⟶ 2CuO

  • In this reaction copper metal has been oxidised since oxygen has been added to it

  • Another example is the reaction of zinc oxide with carbon:

ZnO + C ⟶ Zn + CO

  • In this reaction the zinc oxide has been reduced since it has lost oxygen. The carbon atom has been oxidised since it has gained oxygen. 

Examiner Tips and Tricks

REDOX are simultaneous reactions as they occur at the same time in the same reaction.


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