Table of contents

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



Ca(HCO3)2 → CaCO3 + CO2 + H2O