Grades 9 and 10 - Chemistry - High School - Limestone - Uses of — Flashcards

Limestone is an abundant rock that can be used for a number of purposes. It was formed millions of years ago on the bed of relatively shallow tropical seas. It consists mainly of the mineral calcium carbonate which comes from two sources - shells and precipitation from seawater. There are many types of limestone, some hard, some soft. Rain is naturally slightly acidic because it contains dissolved carbon dioxide which forms a weak acid with water. Carbonates are one of the substances that react with both strong and weak acids, so slowly, over millions of years, rain will dissolve limestone to form some fascinating natural features like limestone sidewalks, caves, stalactites and stalagmites. This corrosion is accelerated by human influence since burning fossil fuels introduces sulfur and nitrogen oxides into the air which makes rain even more acidic.

Many places where limestone appears at the surface of the Earth are areas of great natural beauty. Quarrying raises many issues for local communities and the environment, for example, the destruction of natural habitats and local beauty spots whilst at the same time providing work for local people.

The building industry is a large consumer of limestone and its products, but there are so many more places where it is used. You are not expected to know all of them but it does help if you are aware of some e.g. cosmetics, food manufacturing and agriculture.