This chemical equation represents the reaction of calcium hydroxide (Ca(OH)2) with carbon dioxide (CO2) and sodium carbonate (Na2CO3) to form calcium carbonate (CaCO3) and calcium bicarbonate (Ca(HCO3)2).

2Ca(OH)2 + 2CO2 -> 2CaCO3 + 2H2O
CaCO3 + CO2 + H2O -> Ca(HCO3)2
Ca(HCO3)2 + Na2CO3 -> 2CaCO3 + 2NaHCO3