i. a. Calcium carbonate is prepared by passing carbon dioxide through solution of calcium hydroxide (slaked lime). This results in the formation of water insoluble solid calcium carbonate.
b. However, excess carbon dioxide transforms the precipitate of CaCO3 into water-soluble calcium bicarbonate and therefore, it has to be avoided.
ii. Calcium carbonate can also be prepared by adding solution of calcium chloride to a solution of sodium carbonate. This results in the formation of calcium carbonate as precipitate.
