1. It is prepared by the reaction of magnesium oxide and hydrochloric acid. The chemical equation of the reaction is:
MgO+2HCl====MgCl2+H2O
2. It is prepared by the reaction of magnesium carbonate and hydrochloric acid. The chemical equation of the reaction is:
MgCO3+2HCl=MgCl2+CO2↑+H2O
3. It is prepared by the reaction of magnesium sulfate solution and barium chloride solution. The chemical equation of the reaction is:
MgSO4+BaCl2=MgCl2+BaSO4↓
