1 Marks points to remember
1. The earth’s crust is made up of different minerals embedded in the rocks.
2. Various metals are extracted from these minerals after proper refinement.
3. Minerals are an indispensable part of our lives. Almost everything we use, from
a tiny pin to a towering building or a big ship, all are made from minerals.
4. All living things need minerals and life processes cannot occur without minerals.
5. The hardest mineral is diamond and the softest is talc.
6. Geologists define mineral as a “homogenous, naturally occurring substance with
a definable internal structure.”
7. The physical and chemical condition under which the minerals are formed
makes is so varied.
8. Minerals are usually found in “ores”.
9. The term ore is used to describe an accumulation of any mineral mixed with
other elements.
10.The mineral content of the ore must be in sufficient concentration to make its
extraction commercially viable.
11.The cost of extraction depends on the type of formation or structure in which
minerals are found.
12.In north-east the coal mining is done by tribal family members in the form of a
long narrow tunnel, known as ‘Rat-hole’ mining.
Questions and Answers
Q.1 Describe the main types of formations in which the minerals occur.
Ans. Minerals generally occur in rocks of these forms:
i. In igneous and metamorphic rocks minerals occur in the veins and
the lodes. Major metallic minerals like tin, copper, zinc and lead etc. are
obtained from these veins and lodes.
ii. In sedimentary rocks minerals occur in layers. Coal and some forms of
iron ore are found like this. Minerals such as gypsum, potash salt and
sodium salt are formed as a result of evaporation especially in arid
regions.
iii. In the decomposed surface rocks (a residual mass of weathered
material) Bauxite is formed.
iv. In alluvial deposits or ‘placer deposits’ minerals which are not corroded
by water are found. Such as Gold, silver, tin and platinum.
v. In ocean floor vast quantities of manganese nodules are found.
Common salt, magnesium and bromine are largely derived from ocean
waters.
Distribution of Minerals
1 Marks points to remember
1. Ferrous minerals account for about three-fourths of the total value of the
production of metallic minerals.
2. Iron ore is the basic mineral and the backbone of industrial development.
3. Magnetite ore has a very high content of iron up to 70 per cent.
4. Hematite iron ore is the largest used iron ore in India.
5. Hematite ore from Bailadila (hump of ox) mines are exported to Japan and
South Korea via Vishakapatnam port.
6. The Kudermukh (horse peak) mines located in Karnataka are a 100 per cent
export unit.
7. Kudremukh deposits are known to be one of the largest in the world.
8. This ore is transported from Kudremukh as slurry through a pipeline to a port
near Mangalore.
9. Iron ore from Goa are exported through Marmagao port.
10.Orissa is the largest producer of manganese ores in India.
11.The Balaghat mines in Madhya Pradesh produce more than half of India’s
copper.
12.Bauxite is formed by decomposition of rocks, leaving a residual mass of
weathered material.
13.Bauxite is a clay-like substance from which aluminium is obtained.
14.Orissa is the largest bauxite producing state in India.
15.Mica is a mineral made up of a series of plates or leaves. Mica sheets can be so
thin that a thousand can be layered into a sheet of a few centimeters high.
16.Jharkhand is the leading producer of Mica.
17.Limestone is the basic raw material for the cement industry and essential for
smelting iron ore in the blast furnace.
18.Mining activity is often called a “killer industry” due to high risks involved.
Questions and Answers
Q.2 Describe the distribution of minerals in India.
Ans. India is fortunate to have fairly rich and varied mineral resources.
i. In Peninsular plateau the reserves of coal, metallic minerals, mica and many
other non-metallic minerals are found.
ii. In the sedimentary rocks of Gujarat and Assam most of the petroleum deposits
are found.
iii. In Rajasthan reserves of many non-ferrous minerals are found.
iv. The alluvial plains of north India are almost devoid of economic minerals.
Q.3 Mention the factors which play an important role in affecting the economic
viability of a reserve.
Ans. The factors are:
i. The concentration of mineral in the ore,
ii. The ease of extraction
iii. Closeness to the market.
Ferrous Minerals
Iron Ore
Q.4 What are the two types of iron ore found in India?
Ans. India is rich in good quality iron ores.
i. Magnetite:
a. It is the finest iron ore.
b. It has a very high content of iron up to 70 per cent.
c. It has excellent magnetic qualities, especially valuable in the
electrical industry.
ii. Hematite:
a. This ore is the most important industrial iron ore.
b. It is the largest used iron ore in terms of the quantity.
c. It has slightly lower iron content than magnetite. (50-60 per
cent).
Q.5 Name five largest iron ore producing states of India.
Ans. The five largest iron producing states are Karnataka, Orissa, Chhattisgarh, Goa
and Jharkhand.
Q.6 Describe the four major iron ore belts in India.
Ans. The four major iron ore belts are:
i. O rissa-Jharkhand belt: high grade hematite ore is found.
Important mines are Badampahar and Singbhum mines.
ii. D urg-Bastar belt lies in Chhattisgarh and Maharashtra: Very high
grade hematites are found. Famous mine are Bailadila which
produces iron best suited for steel making.
iii. B ellary-Chitradurga-Chikmaglur-Tumkur belt in Karnataka has
large reserves of iron ore.
iv. M aharashtra-Goa belt includes the state of Goa and Ratnagiri
district of Maharashtra.
Manganese
Q.7 What are the uses of Manganese?
Ans. Manganese is mainly used in the manufacturing of steel and ferro-manganese
alloy. Nearly 10 kg of manganese is required to manufacture one tonne of steel.
It is also used in manufacturing bleaching powder, insecticides and paints.
Non-Ferrous Minerals
Copper
Q.8 What are the uses of Copper?
Ans. India is critically deficient in the reserve and production of copper. Being
malleable, ductile and a good conductor, copper is mainly used in electrical
cables, electronics and chemical industries.
Q.9 Describe the three copper producing regions of India.
Ans. Copper is very low reserves and production of copper.
a. Madhya Pradesh is the largest producer of copper in India. The Balaghat
mines in Madhya Pradesh produce 52 per cent of India’s copper.
b. Rajasthan is the second largest producer of copper. The Khetri mines in
Rajasthan are famous.
c. Jharkhand, the Singbhum district of it is also has large reserves of
copper.
Bauxite (ore of Aluminium)
Q.10 What are the uses of Aluminium?
Ans. Aluminium is an important metal because it combines the strength of metals
such as iron, with extreme lightness and also with good conductivity and great
malleability. It is used in electrical industries, aircraft manufacturing industries,
utensils making, etc.
Non-Metallic Minerals
Mica
Q.11 Why Mica is considered the most important mineral in electric and electronic
industries?
Ans. Due to its excellent di-electric strength, low power loss factor, insulating
properties and resistance to high voltage, mica is one of the most indispensable
minerals used in electric and electronic industries.
Hazards of Mining
Q.12 What are the impacts of mining on the health and the environment?
Ans. The impacts of mining on the health of the miners and the environment are:
i. The dust and noxious fumes inhaled by miners make them vulnerable to
pulmonary diseases.
ii. The risk of collapsing mine roofs, inundation and fires in coalmines are a
constant threat to miners.
iii. The water sources in the region get contaminated due to mining.
iv. Dumping of waste and slurry leads to degradation of land, soil, and increase in
stream and river pollution.
CONSERVATION OF MINERALS
Q.14 Explain why the conservation of minerals is necessary.
Ans. Minerals are important for every country for its development and they need to
be conserved because:
a. Industry and agriculture depend upon minerals and the substances
manufactured from them.
b. Workable minerals are in insufficient quantities. (Just one per cent of
the earth’s crust)
c. We are rapidly consuming mineral resources that require millions of
years to be renewed.
d. The natural rate of replenishment is very small in comparison to the
present rates of consumption.
e. Mineral resources are finite and non-renewable.
f. Mineral deposits in our country will get exhausted in the future.
g. Due to decrease in good quality and they comes from great depths the
costs of mineral extraction is increasing.
Q.15 State how minerals can be conserved for the future generations.
Ans. Mineral conservation can be done by:
i. Use our mineral resources in a planned and sustainable manner.
ii. Improve technology to allow use of low grade ores at low costs.
iii. Recycle metals.
iv. Use scrap metals and other substitutes.
ENERGY RESOURCES
1 Marks points to remember
1. Energy can be generated from fuel minerals like coal, petroleum, natural
gas, uranium and from electricity.
2. More than 70 per cent energy requirement in rural households is met by
firewood and cattle dung cake.
3. Firewood is becoming difficult due to decreasing forest area.
4. Using dung cake is being discouraged because it consumes most valuable
manure which could be used in agriculture.
5. Coal is the most abundantly available and used fossil fuel.
6. Coal is formed due the compression of plant material over millions of years.
7. In India coal occurs in rock series of two main geological ages, namely
Gondwana (200 million years in age) and in tertiary deposits (55 million
years old).
8. Coal is a bulky material, which loses weight on use as it is reduced to ash.
Hence, heavy industries and thermal power station are located on or near
the coalfields.
9. Assam is the oldest oil producing state of India.
10.Natural gas is used as a source of energy as well as an industrial raw
material in the petrochemical industry.
11.The 1700 km long Hazira-Bijaipur-Jagdishpur (HBJ) gas pipeline from
Mumbai High and Bassien provide gas to the fertilizer, power and industrial
complexes in western and northern India.
12.The power and fertilizer industries are the key users of natural gas.
13.Per-capita consumption of electricity is considered as an index of
development.
14.Electricity is generated mainly in two ways: by hydro turbines to generate
hydro electricity; and by burning other fuels such as coal, petroleum and
natural gas to produce thermal power.
15.Uranium and thorium are available in Jharkhand and the Aravalli ranges of
Rajasthan.
16.The Monazite sand of Kerala is also rich in thorium.
17.Photovoltaic technology converts sunlight directly into electricity.
18.The largest solar plant of India is located at Madhapur, near Bhuj (Gujarat).
19.The largest wind farm cluster is located in Tamil Nadu from Nagarcoil to
Madurai.
20.The plants using cattle dung are known as ‘Gobar gas plants’ in rural India.
These provide twin benefits to the farmer in the form of energy and
improved quality of manure.
21.Oceanic tides can be used to generate electricity which is known as Tidal
energy.
22.In India, the Gulf of Kuchchh, provides ideal conditions for utilising tidal
energy.
23.Geothermal energy refers to the heat and electricity produced by using the
heat from the interior of the Earth.
Questions and Answers
Q.16 Differentiate between conventional and non-conventional sources of energy.
Ans. Energy resources can be classified as conventional and non-conventional
sources.
a. Conventional sources of energy are in use form the past whereas the nonconventional
sources are in use from recent times.
b. Conventional sources are mostly polluting in nature whereas nonconventional
sources are eco-friendly.
c. Conventional sources include: firewood, cattle dung cake, coal, petroleum,
natural gas and electricity (both hydel and thermal) whereas nonconventional
sources include solar, wind, tidal, geothermal, biogas and
atomic energy.
Conventional Sources of Energy
Coal:
Q.17 What is the importance of coal in India?
Ans. Coal is an important fossil fuel of India.
a. It provides about 80% of the nation’s energy needs.
b. It is used for power generation.
c. It is used to supply energy to industry as well as for domestic needs.
d. India is highly dependent on coal for meeting its commercial energy
requirements.
Q.18 Describe the four different types of coal found in India.
Ans. Coal is found in a variety of forms.
a. Peat: Decaying plants in swamps produce peat. It has a low carbon and high
moisture contents and low heating capacity.
b. Lignite is a low grade brown coal, which is soft with high moisture content. The
principal lignite reserves are in Neyveli in Tamil Nadu and are used for
generation of electricity.
c. Bituminous coal is buried deep and subjected to increased temperatures. It is
the most popular coal in commercial use.
d. Metallurgical coal is high grade bituminous coal which has a special value for
smelting iron in blast furnaces.
e. Anthracite is the highest quality hard coal.
Q.19 Mention two types of coal reserves found in India.
Ans. Coal in India is found in two geological structures:
i. Gondwana coal: which are metallurgical coal, are located in Damodar
valley (West Bengal-Jharkhand). Jharia, Raniganj, Bokaro coalfields.
ii. Tertiary coal: occur in the north eastern states of Meghalaya, Assam,
Arunachal Pradesh and Nagaland.
Petroleum
Q.20 What are the uses of petroleum in India?
Ans. Petroleum is the next major energy source in India after coal.
i. It provides fuel for heat and lighting,
ii. It is used as lubricants for machinery
iii. It is raw materials for a number of manufacturing industries.
iv. Petroleum refineries act as a “nodal industry” for synthetic textile, fertiliser and
numerous chemical industries.
Q.21 Name important oil fields of India.
Ans. Mineral oil is produced from:
i. About 63 per cent of India’s petroleum production is from Mumbai High,
ii. 18 per cent comes from Gujarat and Ankeleshwar is the most important field
of Gujarat.
iii. 16 per cent from Assam. Digboi, Naharkatiya and Moran-Hugrijan are the
important oil fields in the state.
Natural Gas
Q.22 Name the natural gas fields of India.
Ans. Natural gas is found in:
i. Large reserves of natural gas have been discovered in the Krishna- Godavari
basin.
ii. Mumbai High and the Gulf of Cambay.
iii. Andaman and Nicobar islands are also important areas having large reserves of
natural gas.
Non-Conventional Sources of Energy
Q.23 State why the use of renewable especially non-conventional sources of energy
is becoming necessary in our country?
Ans. The use of non-conventional sources of energy is becoming necessary because:
i. The growing consumption of energy in the country has made us dependent on
fossil fuels such as coal, oil and gas.
ii. Rising prices of oil and gas has eroded our foreign currency reserves.
iii. Shortages in the supply of oil. Gas and coal have increased uncertainties about
the security of energy supply in future,
iv. The growth of the national economy is getting hampered by it.
v. Moreover, increasing use of fossil fuels also causes serious environmental
problems.
Solar Energy
Q.24 Why our country has large potential of using solar energy?
Ans. India is a tropical country. It receives abundant sunshine through out the year
with little cloud cover. Therefore, it has enormous possibilities of tapping solar energy.
Q.25 What are the immediate benefits of using solar energy in our country?
Ans. The benefits are:
i. Solar energy is fast becoming popular in rural and remote areas.
ii. Solar energy is used to sterlise milk cans.
iii. Use of solar energy will be able to minimise the dependence of rural
households on firewood and dung cakes,
iv. Solar energy thus will contribute to environmental conservation and adequate
supply of manure in agriculture.
Biogas
Q.26 What is biogas energy?
Ans. Bio gas is produced from shrubs, farm waste, animal and human wastes. It is
mostly used for domestic consumption in rural areas. Decomposition of organic
matter yields gas, which has higher thermal efficiency in comparison to
kerosene, dung cake and charcoal.
Q.27 What are the benefits of using biogas in rural areas of our country?
Ans. Gobargas and biogas provide many benefits to the farmer:
i. They provide energy to household.
ii. They provide good quality of manure.
iii. Biogas is by far the most efficient use of cattle dung.
iv. It also prevents the loss of trees and manure due to burning of fuel wood and
cow dung cakes.
Conservation of Energy Resources
Q.28 Explain why there is urgent need to conserve energy resources in India.
Ans. Energy resources are very essential for the economic development of India.
a. Every sector of the national economy – agriculture, industry, transport,
commercial and domestic – needs inputs of energy.
b. The success of economic development plans depend on energy
resources.
c. Consumption of energy in all forms has been steadily rising all over the
country.
d. India is presently one of the least energy efficient countries in the world.
Q.29 Mention steps to conserve energy resources in India.
Ans. Energy resources must be judiciously used because our energy resources are
limited.
a. We must use public transport systems instead of individual vehicles;
b. Switching off electricity when not in use,
c. Using power-saving devices and
d. Using non-conventional sources of energy.
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