Delhi Police Constable Exam Model Paper 4

• Limestone is a carbonate sedimentary rock composed primarily of calcium carbonate (CaCO).
• Limestone is the raw material used in the process of manufacturing cement.
• Limestone released carbon dioxide gas while heating.

• Building material.
• Essential component cement industry.
• Aggregate for the base of roads.
• Filler in products such as toothpaste or paints.

CaO is the chemical formula of Calcium oxide.

• Calcium oxide is the most abundant in ordinary Portland Cement.
• Calcium oxide is used for the dehydration of gases.