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Limestone is used for making buildings, and as the base for roads & railways. Limestone is mostly made of
calcium carbonate, and this substance is an important raw material used to make glass, cement &
Limestone is heated when making cement & glass. The heat decomposes the calcium carbonate in it to
form calcium oxide & carbon dioxide. This process is called thermal decomposition.
Calcium carbonate calcium oxide + carbon dioxide
We need to quarry a lot of limestone, but quarrying has economic, environmental & social
effects. We need to balance the effects with the demand