calcium hydrogencarbonate

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A compound, Ca(HCO3)2, that is stable only in solution and is formed when water containing carbon dioxide dissolves calcium carbonate:CaCO3(s)+H2O(l)+CO2(g) → Ca(HCO3)2(aq) It is the cause of temporary hardness in water, because the calcium ions react with soap to give scum. Calcium hydrogencarbonate is unstable when heated and decomposes to give solid calcium carbonate. This explains why temporary hardness is removed by boiling and the formation of ‘scale’ in kettles and boilers.

CaCO3(s)+H2O(l)+CO2(g) → Ca(HCO3)2(aq)

Subjects: Chemistry.

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