Write a brief note on salt.
Salt is a dietary mineral essential for animal life. It is composed primarily of sodium chloride. Salt is produced in different forms; they are unrefined salt or sea salt, refined salt or table salt and iodized salt.
Salt is a crystalline solid, white, pale pink or light grey in color. It is obtained by evaporation of sea water, usually in shallow basins warmed by sunlight.
It is also obtained from rock deposits.
Salt is used in more than 14,000 commercial applications other than in cooking. It is used in the manufacture of pulp and paper and setting dyes in textiles and fabric. It is also used in producing soaps and detergents and for making snow-covered roads safe in winter.
Salt plays an essential role in our daily lives.
Give Reason for Environmental aspects must be carefully looked into before building huge dams.
Pick the Correct Asnwer
(a) Which one of the following is NOT a characteristic of minerals?
(i) They are created by natural processes
(ii) They have a definite chemical composition
(iii) They are inexhaustible
(iv) Their distribution is uneven
(b) Which one of the following is NOT a producer of mica?
(i) Jharkhand (ii) Karnataka (iii) Rajasthan (iv) Andhra Pradesh
(c) Which one of the following is a leading producer of copper in the world?
(i) Bolivia (ii) Ghana (iii) Chile (iv) Zimbabwe
(d) Which one of the following practices will NOT conserve LPG in your kitchen?
(i) Soaking the dal for some time before cooking it
(ii) Cooking food in a pressure cooker
(iii) Keeping the vegetables chopped before lighting the gas for cooking
(iv) Cooking food in an open pan kept on low flame
Which sources of energy would you suggest for (a) rural areas (b) coastal areas (c) Arid Regions?
Give reasons.
(i) Environmental aspects must be carefully looked into before building huge dams.
(ii) Most industries are concentrated around coal mines.
(iii) Petroleum is referred to as "black gold".
(iv) Quarrying can become a major environmental concern.
Answer the following questions.
(i) Name any three common minerals used by you every day.
(ii) What is an ore? Where are the ores of metallic minerals generally located?
(iii) Name two regions rich in natural gas resources.
(iv) Which sources of energy would you suggest for
(a) rural areas (b) coastal areas (c) arid regions
(v) Give five ways in which you can save energy at home.