NCERT Solutions Class 8 Social Science Chapter 3 Mineral and Power Resources

1. Answer the following questions.

(i) Name any three common minerals used by you every day.

Ans. Three common minerals used by us in day to day life are iron, aluminum, gold, salt, etc.

(ii) What is an ore? Where are the ores of metallic minerals generally located?

Ans. Rocks from which minerals are mined profitably are known as ores. The ores of metallic minerals are found in igneous and metamorphic rock formations that form large plateaus.

(iii) Name two regions rich in natural gas resources.

Ans. Regions rich in natural gas resources are Russia, Norway, UK and the Netherlands.

(iv) Which sources of energy would you suggest for

Ans.

(a) Rural areas: Sources of energy that can be used in rural areas are fire wood, coal, solar energy and biogas.

(b) Coastal areas: Tidal energy, wind energy and petroleum can be used in coastal areas.

(c) Arid regions: Geothermal energy and solar energy can be used in arid regions.

(v) Give five ways in which you can save energy at home.

Ans. Five ways in which we can save energy at home are:

1.   Turn off the lights and fans when not needed.

2.   Walk or use bicycle to travel short distances to save fuel.

3.   Use staircase instead of lift.

4.   While cooking, close the vessel to reduce cooking time.

5.   Close the tap when water is not in use.

(i) Which one of the following is NOT a characteristic of minerals?

(a) They are created by natural processes.

(b) They have a definite chemical composition.

(c) They are inexhaustible.

(d) Their distribution is uneven.

(ii) Which one of the following is NOT a producer of mica?

(a) Jharkhand

(b) Karnataka

(c) Rajasthan

(d) Andhra Pradesh

(iii) Which one of the following is a leading producer of copper in the world?

(a) Bolivia

(b) Ghana

(c) Chile

(d) Zimbabwe

(iv) Which one of the following practices will NOT conserve LPG in your kitchen?

(b) Cooking food in a pressure cooker.

(c) Keeping the vegetables chopped before lighting the gas for cooking.

(d) Cooking food in an open pan kept on low flame

3. Give reasons.

(i) Environmental aspects must be carefully looked into before building huge dams.

Ans. Environmental aspects must be carefully looked into before building huge dams. This is because when dams are constructed large areas surrounding the dam are submerged in water. This results in large scale destruction of natural vegetation, wildlife and agricultural land. Construction of dams also displaces settlements. Floods and earthquake threats appear large. Thus, all these aspects must be carefully looked into before constructing a dam.

(ii) Most industries are concentrated around coal mines.

Ans. Most industries are concentrated around coal mines because coal is an important source of energy. It is used as raw material in various industries. So to reduce the transportation cost, most of the industries are located near coal mines.

(iii) Petroleum is referred to as “black gold”.

Ans. Petroleum is referred to as “black gold” because it is black in colour and the derivatives obtained from it are extremely valuable. Varieties of products are obtained from petroleum, like diesel, petrol, kerosene, wax, plastics and lubricants. These products are very useful in our day to day life.

(iv) Quarrying can become a major environmental concern.

Ans. Minerals that lie near the surface are simply dug out, by the process known as quarrying. Quarrying can become a major environmental concern because it destroys the flora and fauna around it. It destroys the humus of soil, which is required for the growth of plants and crops. It produces dust, which causes air pollution and also produces noise pollution.

4. Distinguish between the followings.

(i) Conventional and non conventional sources of energy

(ii) Biogas and natural gas

(iii)  Ferrous and nonferrous minerals

(iv)  Metallic and nonmetallic minerals