CaCO3 + Na2CO3 → CaCO3·Na2CO3 (sodium calcium carbonate)
This reaction results in the formation of a double salt called sodium calcium carbonate. The product is a white precipitate that is insoluble in water. The reaction is typically carried out in an aqueous solution, where the chalk and sodium carbonate are dissolved and then mixed together. The precipitate forms immediately and can be filtered out of the solution.
The reaction can also be represented as follows:
Na2CO3 + H2O + CO2 → 2NaHCO3
CaCO3 + 2NaHCO3 → Ca(HCO3)2
Ca(HCO3)2 → CaCO3 + H2O + CO2
In the first step, sodium carbonate reacts with water and carbon dioxide to form sodium bicarbonate. In the second step, calcium carbonate reacts with two molecules of sodium bicarbonate to form calcium bicarbonate. In the third step, calcium bicarbonate decomposes into calcium carbonate, water, and carbon dioxide.
