NCERT Solutions for Class 8 Social Science Chapter 3 - Minerals and Power Resources

Question 1:

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


Rocks from which minerals are mined are known as ores.
An ore is the natural accumulation of metals or minerals in a concentrated form. It has many impurities.
Generally, ores of the metallic minerals are found in igneous and metamorphic rock formations that form large plateaus.

Question 2:

Which sources of energy would you suggest for: (a) Rural areas (b) Coastal areas (c) Arid areas


I would suggest:
(a) Rural area: Energy sources for rural areas-Biogas
(b) Coastal areas: Hydel power, Wind energy, Tidal energy
(c) Arid areas: Solar energy.

Question 3:

Give five ways in which you can save energy at home


Five ways in which we can save energy at home are as follow:
(a) Switching off the appliances when not in use.
(b) Keeping the lights dust free.
(c) The appropriate maintenance and usage of appliances as per the given instructions.
(d) Maximising the use of natural breeze and light by keeping the windows open.
(e) Using CFL tubelights.

Question 4:

Which one of the following is NOT a characteristic of minerals?


They are inexhaustible

Question 5:

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



Question 6:

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


Cooking food in an open pan kept on low flame.

Question 7:

Give Reason:
Environmental aspects must be carefully looked into before building huge dams.


Dams are built for developing canals and generating water power. But sometimes huge dams cause environmental problems. Many large dams produce environmental impacts upstream, downstream and in the vicinity of the reservoir and hence controversies surround such development. So, all these should be carefully looked.

Question 8:

Give Reason:
Most industries are concentrated around coal mines.


Most industries are concentrated around coal mines because coal is an important source of energy.
It is a key mineral and fuel for the industries. It is used as a power resource in many industries. Many industries use it as a raw material. So, most industries are concentrated around coal mines.

Question 9:

Give Reason:
Petroleum is referred to as black gold.


Now-a-days, petroleum is a major source of energy in the world. Many by-products such as kerosene, fuel, lubricating oils, etc. are obtained from it. Petrochemical products have become very useful. Petroleum is used in agro-industry, paints, perfumes, transport, etc. So it is rightly called black gold.

Question 10:

Give Reason:
Quarrying can become a major environmental concern.


Quarrying can become a major environmental concern because this process is used to dig out those minerals that lie near the surface. It causes land degradation and soil erosion all over the world.

Question 11:

Distinguish between the following.
Conventional and Non-conventional sources of energy.


Question 12:

Distinguish between the following.
Biogas and natural gas.


Question 13:

Distinguish between the following.
Ferrous and Non-ferrous minerals.


(a) Ferrous minerals: These minerals contain iron. For example: Iron ore, manganese and chromite.
(b) Non-ferrous minerals: These minerals do not contain iron but may contain some other metal, i.e., gold, silver, etc.

Question 14:

Distinguish between the following.
Metallic and Non-metallic minerals.