Here's why:
* The Reactivity Series: Metals are arranged in a reactivity series based on their tendency to lose electrons and form positive ions. Metals higher in the series are more reactive than those lower in the series.
* Displacement Reactions: In a displacement reaction, a more reactive metal will displace a less reactive metal from its compound.
* Zinc and Copper: Zinc is higher in the reactivity series than copper. This means zinc has a stronger tendency to lose electrons and form positive ions (Zn²⁺). When zinc is added to a copper sulphate solution (CuSO₄), zinc atoms readily lose electrons, forming zinc ions (Zn²⁺). These ions then combine with the sulphate ions (SO₄²⁻) to form zinc sulphate (ZnSO₄). At the same time, copper ions (Cu²⁺) are displaced from the solution and form solid copper metal.
The chemical equation for the reaction is:
Zn(s) + CuSO₄(aq) → ZnSO₄(aq) + Cu(s)
