This is a precipitation reaction: CaCO3 is the formed precipitate.
This is a gas evolution reaction, CO2 is the formed gas.
Input interpretation
Ca(HCO3)2 → CaCO3 + CO2 + H2O
Calcium carbonate carbon dioxide water
Balanced equation
Balance the chemical equation algebraically:
Ca(HCO3)2 → CaCO3 + CO2 + H2O
Add stoichiometric coefficients, c, to the reactants and products:
c1Ca(HCO3)2 → c2CaCO3 + c3CO2 + c4H2O
Set the number of atoms in the reactants equal to the number of atoms in the products for Ca, H, C and O:
Ca: c1 = c2
H: 2c1 = 2c4
C: 2c1 = c2 + c3
O: 6c1 = 3c2 + 2c3 + c4
Since the coefficients are relative quantities and underdetermined, choose a coefficient to set arbitrarily. To keep the coefficients small, the arbitrary value is ordinarily one. For instance, set c1 = 1 and solve the system of equations for the remaining coefficients:
c1 = 1 c2=1
c3 = 1 c4=1
Substitute the coefficients into the chemical reaction to obtain the balanced
equation:
Answer:
Ca(HCO3)2 → CaCO3 + CO2 + H2O