Describe the importance of the following : (i) limestone (ii) cement (iii) plaster of paris.
(i) Limestone is used (a) as a building material in the form of marble. (b) in the preparation of quicklime. (c) as a raw material in ammonia soda process for the manufacture of sodium carbonate. (d) as a constituent of toothpaste. (e) as a filler in cosmetics. (ii) Cement is used in (a) concrete and reinforced concrete. (b) plastering. (c) the construction of buildings, bridges , dams, etc. (iii) Plaster of paris is used (a) in building industry. (b) in plasters. (c) for making statues, models and other decorative materials. (d) in surgical bandages (plasters) for immobilizing the fractured base in the body.