CC3.2 — Reactivity series (Edexcel 1SC0)

Reactivity series (most to least reactive)

K, Na, Li, Ca, Mg, Al, C, Zn, Fe, (H), Cu, Ag, Au, Pt

More reactive metals displace less reactive metals from their compounds.

Displacement reactions

A more reactive metal displaces a less reactive metal from a solution of its salt.

Example: Zn + CuSO₄ → ZnSO₄ + Cu (zinc is more reactive than copper).

Observations: copper metal deposits on zinc; blue solution fades; zinc surface turns brown/pink.

Oxidation and reduction (in terms of oxygen)

• Oxidation: gain of oxygen.
• Reduction: loss of oxygen.
• OIL RIG (electrons): Oxidation Is Loss; Reduction Is Gain.

In displacement: the metal being displaced is reduced (gains electrons); the displacing metal is oxidised (loses electrons).

Rusting

Iron + water + oxygen → hydrated iron(III) oxide (rust).

Prevention: painting, oiling, galvanising (zinc coating), sacrificial protection (attach more reactive metal like magnesium — it oxidises instead of iron).