What is lime stone? How is it prepared? Give its properties and uses.
Limestone or marble is calcium carbonate (CaCO3).
Preparation: In the laboratory, it is prepared by the action of sodium carbonate on calcium chloride when a white precipitate of calcium carbonate is obtained.
Properties: (i) It is a white powder, sparingly soluble in water.
(ii) On heating to about 1200K, it decomposes to form calcium oxide.
Uses: It is used
(i) in the form of marble for making floors.
(ii) in toothpaste.
(iii) in the form of fine powder in face powders and
(iv) in the form of limestone for making lime, cement and glass.
How is quick lime prepared on a commercial scale? How is it converted into slaked lime?
What is the effect of heat on the following compounds? (Write equations for the reactions):
(i) Calcium Carbonate
(ii) Magnesium chloride hexahydrate
(iii) Gypsum
(iv) Magnesium sulphate heptahydrate