Metals can be arranged in an activity series

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ntThe metals in the activity series are arranged in order of how easily they are oxidised to form positive ions

• Form positive ions more easily

• Therefore, more reactive

• Lose electrons more readily

• Stronger reducing agents

Metals higher up the series :

• The metals high in the activity series displace those lower in the series from solutions of their salts.

For instance, when a piece of zinc is put in a solution containing copper(II) ions,

• The zinc becomes coated with copper

• The blue colour of the solutions fades

• The solutions get warmer

CuSO4 (aq)

Zn

• Zinc displaces copper from solution – this is called a displacement reaction or a single replacement reaction

• Zn(s) + Cu2+ (aq) Zn2+

(aq) + Cu (s)

Oxidation

Reduction