The chemical formula of calcium carbonate is CaCO3. The elements calcium, carbon and oxygen form the compound calcium carbonate. This compound is available in the nature in the form of sedimentary rock like limestone, metamorphic rock like marble. It is extracted from the rock forming minerals such as calcite and travertine. Calcium carbonate has very many uses in the real world.
Calcium is an important mineral needed by us and other living organisms. In humans, it is very important for bone formation and teeth formation. Plants and animals absorb calcium carbonate from water where it is found in the form of calcium bicarbonate (calcium hydrogen carbonate) to build their skeletons and shells. The main components of shells of marine organisms, snails, pearls, coral, and a number of sea shells is calcium carbonate. Egg shells are made of approximately 95% calcium carbonate. When plants and animals die, the compound is returned to nature aiding in rock formation.
Pure material is a soft, white, insoluble powder. This powder used in the form of thin sticks makes the Chalks that are used as teaching aid.
The mineral calcite is used by the construction industries to produce cement, concrete, and manufacture of iron, steel and glass. When calcium carbonate is heated, it decomposes into lime and carbon dioxide which are further used as raw material.
Lots of products that we use at home like toothpaste, shoe polish, bathroom cleaner, and baking soda contain calcium carbonate. It is also used in baby diapers, cake mixes and food coloring. The other important use is as medicine to make up for calcium deficiencies and also neutralizing stomach acid. Hard water deposits (scales) that form in the bathroom, kitchen sink are calcium deposits.
Calcium carbonate reacts uniquely with acids. When it comes in contact with acid, however strong it may be, it produces carbon dioxide. This results in the natural phenomena stalactites and stalagmites which takes more than thousands of years to form.