2Ba(OH)2 + Mg(HCO3)2 = Mg(OH)2↓+2BaCO3↓+2H2O;
本来2Ba(OH)2 + Mg(HCO3)2 = Mg(OH)2↓+2Ba(HCO3)2↓由于Ba(HCO3)2物质不稳定分解为BaCO3↓和H2O;