ADDITIONAL QUESTIONS

  ADDITIONAL QUESTIONS :

Answer the following questions :

1.  What is a mineral .
Ans: Minerals are found in the earth and are naturally occurring substances. They are not made by man. They are found in rocks and water. They are chemical substances made of elements .

2.  How are minerals extracted from earth .
Ans: Minerals are extracted by mining, drilling and quarrying .

3.  What are the classification of the minerals .
Ans: They are classified into metallic minerals and Non-metallic minerals.Metallic mineral are further divided into ferrous and non-ferrous minerals .

4.  What do the three R’s stand for .
Ans: It stands for Reduce, Reuse and Recycle .

Reduce – to use lesser quantity .
Reuse – to put it again into use without changes .
Recycle – to put it again into use with changes .

5.  What is bio-gas .
Ans: It is gaseous fuel obtained from the  decomposition of organic wastes like dead plants and animal material or animal dung .

6.  Mention few minerals and their uses .
Ans:

i) Gold, Silver and Platinum are used in jewellery .
ii) Copper is used in the coin industry and for making pipes and wires .
iii) Silicon obtained from quartz is used in the  computer industry .
iv) Aluminium obtained from bauxite ore is used in automobiles and airplanes, buildings and even in kitchen cookware .

7.  What is a) Extraction , b) Mining , c) Shaft mining and  d) Quarrying  .
Ans:

a) Extraction is the process of taking out minerals from under the earth’s surface so that useful materials can be derived from them .
b) Mining – is a process of extraction ( taking out) of minerals from rocks under the earth’s surface .
c) Shaft mining – is a method of extraction in which deep bores (called shaft) are made to reach the mineral deposits lying deep under the earth .
d) Quarrying  – is the process of extraction in which minerals lying very close to the surface are extracted just by digging them out .

8.  What are fossil fuels .
Ans: Fossil fuels are what the remains of plants and animals got  converted into after they remained buried under the earth million years ago .

9. Define Geothermal energy.
Ans: Heat energy obtained from the earth is called geothermal energy.

10. What are the uses of minerals?
Ans: Minerals are used in many industries. Minerals which are used for gems are usually hard.  These are then set in various styles of jewellery. Copper is another metal used in everything from coins to pipes, silicon used in computer industry is obtained from quartz. Aluminium obtained from its ore bauxite is used in automobiles and aeroplanes, bottling industry, buildings and even in kitchen cookware.

11. What is coal and why is coal referred to as Buried Sunshine?
Ans: Coal is the most abundantly found fossil fuel. It is used as a domestic fuel, in industries such as iron and steel, steam engines and to generate electricity. Electricity from coal is called Thermal Power.The coal which we are using today was formed millions of years ago when giant ferns and swamps got buried under the layer of earth. Coal is therefore referred to as Buried Sunshine.

12. Define Tidal Energy and where was the first tidal energy station built?
Ans: Energy generated from tides is called tidal energy. Tidal energy can be harnessed by building dams at narrow openings of the sea. During high tide the energy of the tides is used to turn the turbine installed in the dam to produce electricity.

13. What is meant by Nuclear power? Explain the process how it is obtained. 
Ans: Nuclear power is obtained from energy stored in the nuclei of atoms of naturally occurring radio active elements like uranium and thorium. These fuels undergo nuclear fission in nuclear reactors and emit power.