Question

Describe the importance of the following:
(i) limestone
(ii) cement
(iii) plaster of paris

Answer 1

Hint: Limestone is calcium carbonate. The raw materials used in the manufacture of cement are clay and limestone. Plaster of paris is calcium sulphate hemihydrate.

Complete step by step answer:
(i) The importance of the limestone:
(a) Limestone is present in marble. You can use marble as a building material and construction work.
(b) You can prepare quicklime from limestone.
(c) Ammonia soda process is used to prepare sodium carbonate. You can use limestone as a raw material in this process.
(d) One of the main ingredients of toothpaste is limestone.
(e) In the cosmetics industry, you can use limestone as a filler.
(ii) The importance of the cement:
(a) You can use cement in concrete and reinforced concrete.
(b) You can use cement for plastering purposes.
(c) You can also use the cement for building construction, making bridges and dams.
(iii) The importance of the plaster of paris:
(a) You can use the plaster of paris in the construction industry.
(b) You can also use the plaster of paris in plasters.
(c) To make statues, models and other decorative materials, you can use the plaster of paris.
(d) The surgical bandages (plasters) are needed to immobilize the part of the body that is having fractures. You can use the plaster of paris for this purpose.

Note: Don’t confuse between the gypsum and plaster of paris. The chemical formula of gypsum is $CaSO_4.2H_2O$. When it is dehydrated it forms calcium sulphate anhydrous with the chemical formula $CaSO_4.1/2H_2O$. This is known as plaster of paris.
There are several uses of each substance. The uses of one substance are different from the uses of other substances.