3. Mineral and Power Resources


Ncert solution for class 8 social science Geography chapter-03.

Question. 1. Answer the following Question.
 (i) Name any three common minerals used by you every day.
Answer-Three common minerals used by us in day-to-day life are copper, iron and salt.
(ii) What is an ore? Where are the ores of metallic minerals generally located?
Answer-An ore is a rock from which minerals are mined. Ores of metallic minerals are found usually in igneous and metamorphic rock formations.
(iii) Name two regions rich in natural gas resources.
Answer-  Two regions in India rich in natural gas resources are: Jaisalmer and Krishna-Godavari delta.
(iv) Which sources of energy would you suggest for (a) rural areas (b) coastal areas (c) arid regions
Answer-(a) For rural areas, solar energy and wind energy are feasible options. There aren’t many high-rise buildings to act as obstacle for sunlight or to break the momentum of wind” .    
(b) For coastal areas, wind energy and tidal energy are good choices.
(c) For arid regions, wind energy and solar energy are feasible, for reasons similar to rural areas.

tidal-energy-MINERAL-AND-POWER-RESOURCE-CLASS-8


(v) Give five ways in which you can save energy at home.
Answer- Five ways in which one can save energy at home:
1. Promoting the use of solar energy as much as possible.
2. Using biogas as cooking fuel.
3. Drying clothes in sunlight instead of electric dryers to prevent emissions and unnecessary use of electricity.
4. Avoiding misuse of electricity; switching off fans and lights when not required.
5. Using pressure cookers for cooking.

Question. 2. Tick the correct answer-
(i) Which one of the following is not a characteristic of minerals?      
Answer- (c) They are inexhaustible.
(ii) Which one of the following is not a producer of mica?                                   
Answer- (b), Karnataka
(iii) Which one of the following is a leading producer of copper in the world?              
Answer-( c)  Chile
(iv) Which one of the following practices will not conserve LPG in your kitchen?
Answer-(d)  Cooking food in an open pan kept on low flame.

Question. 3   Give reasons.

(i) Environmental aspects must be carefully looked into before building huge dams.
Answer- Building huge dams causes destabilisation of the natural habitats of plants and wild animals living in the area. These environmental aspects should be looked into before building dams.
(ii) Most industries are concentrated around coal mines.
Answer-Presence of coal mines around industries reduces the costs of transportation and also ensures easy availability of fuel.
(iii) Petroleum is referred to as “black gold”.   
Answer-Petroleum is a very valuable fossil fuel. It is used for running all machineries, transport vehicles, from a bicycle to an aeroplane.
(iv) Quarrying can become a major environmental concern.
Answer-After quarrying, pits are not covered so they may cause environmental hazards.

Question. 4. Distinguish between the followings.
(i) Conventional and non-conventional sources of energy.
Answer-
1. Conventional :- The conventional sources of energy are non-renewable. These resources are available in a limited quantity. examples -CNG, coal, oil, natural gas
2. Non-conventional:- Non-conventional energy resources are renewable. Non-conventional energy sources are eco-friendly in nature. examples - Solar Energy, Wind Energy,
 
Geothermal-Energy-MINERAL-AND-POWER-RESOURCE-CLASS-8

 (ii) Biogas and natural gas.
Answer-  1.Biogas :- It is a renewable source of energy. It is a naturally occurring gas that is formed from fossil fuel.  It is a Non-conventional source.
2. Natural gas:- It is a non-renewable source of energy. It is a conventional source. It is a naturally occurring gas that is formed from the break-down of organic matter in the presence of anaerobic bacteria.
(iii) Ferrous and non-ferrous minerals.
Answer-  
1.Ferrous minerals:
Ferrous minerals are those not containing iron. They are magnetic.
Examples: Iron ore and manganese.
2. Non-Ferrous minerals:
Non-Ferrous minerals are those containing iron. They are not magnetic.
Examples: copper, gold  
(iv) Metallic and non-metallic minerals.
Answer-
1. Metallic minerals: - Metallic minerals contain metal in raw form. They are usually hard and have shine of their own. Iron, copper
2. Non-metallic minerals: - Non-metallic does not contain metals. They are not usually hard and have no shine of their own. Salt, coal,

EXTRA QUESTIONS
Question. 1. Differentiate between a rock and an ore.
Answer-A rock is an aggregate of one or more minerals. An ore is a rock from which minerals are mined.
Question. 2. Name two areas in Australia, which have large deposits of gold.
Answer-Two areas in Western Australia having large deposits of gold are Kalgoorlie and Coolgardie.
 Question. 3. Why are minerals considered non-renewable?
Answer-- Minerals take thousands of years to form. The rate of formation is much smaller than rate of consumption. So we classify them as non-renewable.