Limestone is a rock that is mainly made of calcium carbonate
Limestone is widely used in building.
Limestone breaks down when we heat it strongly (thermal decomposition) to make quicklime and carbon dioxide
Limestone - calcium carbonate = CaCO3
Quicklime - Calcium oxide = CaO
Slaked lime - Calcium hyroxide - Ca(OH)2
Uses of limestone
To make buildings
Mix sand, sodium carbonate and powdered limestone at a high temperature to make glass
Powdered limestone and powdered clay mixed and heated makes cement. Also cement powder with water, sand and crushed rock mixed together makes concrete.
Used in the blast furnace
Slaked Lime, Sand and Water mixed creates Mortar