Q. What is formed when Carbon Dioxide is passed through Lime Water? Answer:
Calcium Carbonate
Notes: When Carbon dioxide is passed into limewater, it gives a milky or turbid solution. This is due to the insoluble suspension of calcium carbonate formed:
Ca(OH)2 (aq) + CO2 (g) + CaCO3 (s) + H2O(l).
However, when excess of carbon dioxide is passed through the solution, the turbidity disappears, and a clear solution is obtained due to the formation of calcium bicarbonate, which is soluble in water.