Temporary hardness can be removed by boiling the water and then filtering it. The Calcium and magnesium bicarbonates present in temporarily hard water form insoluble precipitates on boiling the water. The Carbon dioxide present in bicarbonates is also removed during boiling. Ca(HCO3)2 → CaCO3↓ + CO2 + H2O. In this reaction, CaCO3 is the insoluble precipitate which can be filtered out. CO2 gas is evolved, and soft H2O is left behind.