Calcium oxide ⟶ Calcium chloride ⟶ Calcium carbonate
- CaO + 2HCl ⟶ CaCl2 + H2O
- CaCl2 + Na2CO3 ⟶ 2NaCl + CaCO3
Zinc sulphide ⟵ Zn ⟶ Zinc sulphate
- Zn + S ⟶ ZnS
- Zn + H2SO4 ⟶ ZnSO4 + H2
Iron [II] chloride ⟵ Fe ⟶ Iron [III] chloride
- Fe + 2HCl ⟶ FeCl2 + H2
- 2Fe + 3Cl2 ⟶ 2FeCl3
Lead [II] oxide ⟶ Lead nitrate ⟶ Lead sulphate
- PbO + 2HNO3 ⟶ Pb(NO3)2 + H2O
- Pb(NO3)2 + Na2SO4 ⟶ 2NaNO3 + PbSO4
Copper [II] oxide ⟶ Copper [II] sulphate ⟵ Copper [II] hydroxide
- CuO + H2SO4 ⟶ CuSO4 + H2O
- Cu(OH)2 + H2SO4 ⟶ CuSO4 + 2H2O