What is a redox reaction?
In GCSE Chemistry, a redox reaction is a chemical reaction in which both reduction (gain of electrons) and oxidation (loss of electrons) occur simultaneously. These reactions are seen in processes such as displacement reactions, combustion, corrosion, and electrolysis.
For example, in the reaction between zinc and copper sulfate:
Zn + CuSO₄ → ZnSO₄ + Cu
zinc loses electrons to form zinc ions (oxidation)
copper ions gain electrons to form copper metal (reduction)
To remember the definitions of oxidation and reduction, the term 'OIL RIG' can be used:
Oxidation Is Loss (of electrons), Reduction Is Gain (of electrons)
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For more information about redox reactions check out the following resources:
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