CBSE Class 8 Geography Chapter 3 Mineral and Power Resources– Detailed explanation of the chapter ‘Mineral and Power Resources’ along with question answers. Given here is the complete explanation of the lesson, along with all the exercises, Question and Answers given at the back of the lesson.
Class 8 Geography Chapter 3 – Mineral and Power Resources
Introduction
Mineral is a substance that occurs naturally and has definite chemical composition. They are not distributed in an even manner. They can be found concentrated in a particular area or in a rock formation. Few kinds of minerals can be found in areas which one cannot access easily at places such as Antarctica and the ocean bed of the Arctic.
Minerals can be found under varying conditions in geological environments of different types. They are created with the help of natural processes and no human interference is required for this. One can identify minerals with the help of physical properties such as density, hardness, colour and chemical properties like solubility.
Mineral and Power Resources Class 8 Video Explanation
Types of Minerals
More than three thousand different types of minerals can be found on this planet. Metals can be classified as metallic and non-metallic on the basis of their composition.
Those minerals which consist of metals in its raw form are called metallic minerals. They are hard substances that are capable of conducting electricity and heat. They are lustrous or shiny in nature. Examples of metals are Manganese ore, Iron ore and Bauxite ore are few examples of metals.
Metallic minerals can be further classified as non-ferrous or ferrous. Non-Ferrous metals do not have iron as their main composition but other metals such as silver, lead, copper or gold. Ferrous metals have iron as one of their main components.
Those minerals which are non-metallic do not have metals as their main components. The examples of such minerals are gypsum, limestone and mica. Mineral fuels such as petroleum and coal are other examples.
The process of extracting minerals is of drilling, mining or quarrying.
Mining is the process in which minerals are taken out from those rocks which are buried under the surface of earth. Those minerals which are present in shallow depths are taken out once the layer of surface is removed, this process is known as open-cast mining. Deep Bores which are known as shafts are made out in order to reach the deposits of minerals that lie at great depths. This process is known as shaft mining.
Minerals such as natural gas and petroleum are present far below the surface of earth. In order to take them out, deep wells are bored. This process is called drilling. Those minerals which can be found easily near the surface of earth can be simply dug out by the process called as quarrying.
Distribution of Minerals
Minerals can be found in different varieties of rocks. They are found in different types of rocks such as sedimentary rocks, metamorphic rocks and igneous rocks. Metamorphic and igneous rock formations consist of metallic minerals that form large plateaus. Nickel and copper deposits are found in Ontario (Canada), Iron ore found in North Sweden. Chromites, Iron, Platinum and Nickel are found in South Africa. These minerals are found in igneous and metamorphic rocks. Young fold mountains and plains formed by Sedimentary Rocks consist of non-metallic minerals such as limestone. Manganese deposits in Georgia, Limestone deposits in France’s Caucasus region and Algeria’s Phosphate beds are few of the examples of non-metallic deposits. Petroleum and Coal can also be found in sedimentary regions.
Asia
India and China have large Iron ore deposits. More than half of tin produced across the world comes from this continent. Indonesia, China and Malaysia are some of the leading tin producers. Tungsten, lead and Antimony are produced in abundant amounts in China. Deposits of bauxite, manganese, copper, nickel and Zinc can also be found in Asia.
Europe
Europe is the top most producer of iron-ore in the world. The countries that consist of iron ore deposits in large amounts are Ukraine, France, Russia and Sweden. Mineral deposits of zinc, copper, manganese and lead can be found in European Russia and Eastern Europe.
North America
The mineral deposits of North America can be found in three zones: Western Mountain regions, the Appalachian region and Great Lakes of North Canada. Canadian Shield Region consists of iron ore, gold, uranium, nickel and copper. The Appalachian region has Coal. Vast deposits of gold, lead, silver and copper are present in Western Cordillera region.
South America
The largest producer of iron ore of high grade in the world is Brazil. Peru and Chile lead in Copper production. Tin can be found in high amounts in Bolivia and Brazil. Large deposits of Silver, Chromium, Gold, Manganese, Platinium, Bauxite, Asbestos, Mica and Diamond can be found easily in South America. Columbia, Argentina, Chile, Venezuela and Peru are producers of Mineral Oil.
Africa
The continent has a large presence of mineral resources in abundant amounts. Platinum, Diamond and Gold are found in high amounts in Africa. Zaire, South Africa and Zimbabwe produce gold in large quantities. Few other minerals that are located in this continent are Chromium, Cobalt, Iron ore, Uranium, Copper and Bauxite. Oil can be found in countries such as Angola, Libya and Nigeria.
Australia
The country is the largest producer of bauxite. Other minerals found in huge quantities are Iron Ore, Nikel, Gold, tin and diamond. Zinc, copper, lead and manganese are some of the other minerals to be found. Western Australia regions such as Coolgardie and Kalgoorlie hold some of the leading deposits of gold.
Antarctica
Scientists are aware of the geology of this continent. They have predicted that the continent has few of the minerals present in large amounts. Prince Charles mountains present in East Antarctica are estimated to have iron deposits. Similarly, it has been forecasted that Transantarctic mountains may have deposits of coal in huge amounts. Other important minerals such as oil, gold, silver and iron ore are also found in abundant quantities.
Uses of Minerals
Different industries need to use minerals in order to sustain. Those minerals that are used in manufacturing of gems are hard in nature. After that, different designs are prepared in order to set them in style. Copper is a metal which is used to manufacture pipes, utensils, coins. Silicon is obtained from quartz which is used in the computer sector. Aluminium can be obtained from the ore of bauxite. It is used in manufacturing buildings, kitchen equipment, airplanes, automobiles.
Conservation of Minerals
Minerals are one of the non-renewable resources provided by nature. The process of concentration and formation of these minerals can take over thousands of years. The rate at which these minerals are formed is far more slower than people use it for their benefits. Hence, it is important that the authorities should introduce necessary steps to reduce wastage in the process of mining. Another way to conserve these metals is Recycling.
Power Resources
Energy or power have an important role to play in our lives. They are needed in various sectors such as agriculture, communication, defense and industry. Power resources are divided into two categories – Conventional and non-Conventional.
Conventional Resources
Those energy resources which have been in use for a long time are known as Conventional Resources. Examples of such resources are Fossil fuels and firewood.
Firewood
It is mostly used for heating and cooking. In India, around 50 percent of energy that the villagers utilize for their daily usage comes from firewood.
Millions of years back, remains of animals and plants had got buried under the earth. Due to pressure and heat, they got converted into fossil fuels. Fossil fuels such as natural gas, petroleum and coal are few of the main resources of conventional energy. However, the reserves of such minerals are found only in limited amounts. The rate of world population is increasing at a high speed and they need these resources in abundant amounts which is slower than formation of such resources. Therefore, many of these resources can get exhausted any time.
Coal
It is an example of fossil fuel which is found in huge amounts across the globe. Coal is utilized in the form of domestic fuel, such as steel and iron, and also in steam engines in order to generate electricity. Electricity which can be generated from coal is known as thermal power. When giant swamps and ferns got buried under the layers of earth – it led to formation of coal due to high temperature as well as pressure. Due to this, coal is also referred to as Buried Sunshine. France, China, Germany, USA, France and South Africa are some of the leading producers of coal across the globe. In India, coal can be found in abundant amounts in cities such as Jharia, Bokaro, Raniganj and Bokaro – all present in the state of Jharkhand.
Petroleum
The oil that saves our cycle from getting squeaked and petrol that keeps the car running are derived from a thick black liquid named Petroleum. It can be located between layers of rocks and is drilled from the areas located in off-shore regions across the coastal areas. After this, the oil is sent to refineries where the crude oil is processed. With this, a variety of products such as wax, lubricants, diesel, plastic, kerosene and petrol are manufactured. Since, petroleum as well as its products are valuable in nature. They are also referred to as Black Gold. Qatar, Iran, Saudi Arabia and Iraq are some of the countries that produce petroleum. The other major producers of petroleum are Venezuela, USA, Russia and Algeria. In India, oil can be found in deltas of Godavari and Krishna rivers, Bombay High (Mumbai) and Digboi (Assam).
Natural Gas
This gas is usually found with petroleum deposits. As the crude oil is brought to the surface of earth, the natural gas also gets released. It is utilised as industrial as well as domestic fuel. Netherlands, Norway, UK and Russia are few of the major producers of natural gas.
In India, Godavari – Krishna delta, Tripura, Mumbai’s shore areas and Jaisalmer are few of the places where natural gas are located. There are only a handful of countries that have natural gas reserves in sufficient amounts.
Due to an increase in population, people’s dependence on fossil fuels have increased in massive amounts. After you burn these fossils, it releases toxic gases in massive amounts which is also a major cause of concern. Keeping the usage of fossil fuels unchecked is like keeping a dripping tap unchecked. Due to this, usage of several non-conventional resources have been introduced which are clean in nature and a better alternative.
Hydel Power
River water or rain water that are stored in dams fall from a significant height. The water which falls down with the help of pipes in the dam over blades of turbines that are placed at the dam’s bottom side. The generator gets turned on due to a moving blade which in turn produces electricity. The electricity generated by this process is called hydroelectricity. The water which gets discharged after generation of electricity is used for the process of irrigation later on.
Hydel Power is responsible for providing power to one fourth of the population across the globe. China, Paraguay, Brazil and Norway are some of the biggest producers of hydel power. Damodar Valley, Nagarjuna Sagar, Gandhi Sagar and Bhakra Nangal are some of the important projects of hydel power in India.
Non-Conventional Sources of Energy
As the fossil fuels are being utilized in high amounts, this has led to their shortages. The reserves of fossil fuels could get exhausted soon if its consumption continues at a rapid rate. Apart from that, their usage also causes environmental pollution. Hence, it is required that we start using non-conventional energy resources such as tidal energy, solar energy and wind energy which are renewable in nature.
Solar Energy
Sun provides us light and heat which are felt on a daily basis. Solar energy is trapped in solar cells from the sun and in turn, is used to generate electricity. These cells are joined in order to form solar panels so that electricity can be generated for lighting and heating purpose. Various tropical countries get sunshine in abundant amounts. Solar energy is also used in devices such as solar dryers, solar heaters, solar cookers, etc. Nowadays, it is also used in traffic lights and for lighting the community arenas.
Wind Energy
It is a type of energy resource which doesn’t get exhausted easily. Since ancient times, windmills have been used to grind grains and lift water. Nowadays, windmills rotate with the help of high speed wind that is conducted with a generator in order to produce electricity. Mountain passes and coastal regions have wind farms present in clusters. These regions have steady and strong wind flow. Countries such as Germany, Netherlands, USA, Spain and Denmark rely on wind energy a lot.
Nuclear Power
The energy that is stored in atoms’ nuclei that occurs in radioactive elements naturally. Thorium and uranium are some of the examples of radioactive elements used. In nuclear reactors, the nuclear fuels have to undergo nuclear fission which in turn produces power. Europe and the USA are some of the greatest producers of nuclear power. In India, Jharkhand and Rajasthan have a huge quantity of Uranium. Kerala’s Monazite sands also have Thorium deposits. Kaiga (Karnataka); Ranapratap Sagar, Kota (Rajasthan); Tarapur (Maharashtra); Narora (Uttar Pradesh) and Kalpakkam (Tamilnadu) are some of the nuclear reactors of India.
Geothermal Energy
Heat energy which can be obtained from earth is known as Geothermal energy. As we godeeper, the temperature of earth’s interior starts rising in a steady manner. Sometimes, heat energy takes the form of hot springs. It is utilized to generate power.
Geothermal energy which is found in the form of hot springs is used for bathing, cooking and heating. World’s largest geothermal power plant is located in the USA. Central America, New Zealand, Philippines and Iceland are other sources of this energy. In India, geothermal plants exist in Ladakh’s Puga valley and Himachal Pradesh’s Manikaran.
Tidal Energy
When energy is generated with the help of tides, it is called tidal energy. When dams are built at a sea’s narrow openings, it is used to harness tidal energy. As the high tide occurs, their energy can be utilised to turn on the turbine installed with dams so that electricity could be produced. The Gulf of Kachchh in India, France and Russia have some of the huge tidal mill farms of the world.
Biogas
Dead animal and plant material, kitchen waste and animal dung are some of the examples of organic waste that can be converted into biogas. It is a gaseous fuel. In Biogas digesters, bacteria helps to decompose organic matter. The organic waste is decomposed by bacteria in biogas digesters to emit biogas which is essentially a mixture of methane and carbon dioxide. Biogas is an excellent fuel for cooking and lighting and produces huge amount of organic
manure each year. Biogas is capable of producing organic manure in huge amounts every year. It is also used while cooking.
Energy is found everywhere. However, we need to understand that it is difficult and expensive to harness energy. Hence, we should avoid wasting energy. The energy generated has to be saved as well. It will be beneficial for our future generation.
Question and Answer
Q (i). Name any three common minerals used by you every day.
Answer. Iron, Aluminium and Quartz.
Q (ii). What is an ore? Where are the ores of metallic minerals generally located?
Answer: Ore is a type of rock from which a specific type of mineral is extracted for profitable purposes. Ores of metallic minerals are usually located in metamorphic and indigenous rocks.
Q (iii). Name two regions rich in natural gas resources.
Answer. Bombay High and Krishna – Godavari Delta are the two regions of our country which are rich in natural gas resources.
Q (iv). Which sources of energy would you suggest for
(a) rural areas (b) coastal areas (c) Arid regions
Answer:
(a) rural areas: Biogas
(b) coastal areas: Tidal Energy
(c) Arid regions: Solar Energy
Q (v). Give five ways in which you can save energy at home.
Answer: These five ways are:
- Switch off lights and fans when not in use.
- Use conventional sources of energy such as Biogas, Solar Energy, etc.
- Soak food items such as pulses for a significant amount of time before you go for cooking.
- Minimize the use of ACs.
- Use a pressure cooker while cooking certain dishes.
Q 2. Tick the correct answer.
(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.
Answer: (c) They are inexhaustible.
(ii) Which one of the following is a leading producer of copper in the world?
(a) Bolivia (c) Chile
(b) Ghana (d) Zimbabwe
Answer: (c) Chile
(iii) Which one of the following practices will NOT conserve LPG in your kitchen.
(a) Soaking the dal for some time before cooking it.
(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.
Answer: (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.
Answer: When the huge dams are constructed in any particular region, natural wildlife and vegetation end up getting destroyed on a large scale. A large section of area also gets submerged which creates major issues for the ecosystem. Therefore, it is important to look into environmental aspects before a dam is about to be built.
(ii) Most industries are concentrated around coal mines.
Answer: Coal is a non-renewable energy resource that provides energy to those industries lying around it. Hence, most industries are concentrated around coal mines.
(iii) Petroleum is referred to as “black gold”.
Answer. Petroleum is a valuable resource which is used in different industries. It is also black in colour originally. Hence, it is referred to as ‘Black Gold.’
(iv) Quarrying can become a major environmental concern.
Answer: Due to quarrying, many serious issues have arisen. A quarrying site has fine dust particles in huge amounts which is hazardous to people working in these sites along with the environment. In order to carry out quarrying works, many natural vegetation sites have been destroyed as well. Hence, it is an environmental concern.
4. Distinguish between the following:
(i) Conventional and non-conventional sources of energy
Answer:
S. no. |
Conventional Energy Sources |
Non-Conventional Energy Sources |
1. |
They are presented in a limited amount. |
They are present in unlimited amounts. |
2. |
They do not get replenished continuously. |
They get replenished continuously with the help of natural processes. |
3. |
They are also called non-renewable energy sources. |
They are called renewable energy sources. |
4. |
Example: Coal, Petroleum |
Example: Solar Energy, biogas |
(ii) Biogas and natural gas
S. no. |
Biogas |
Natural Gas |
1. |
It is a renewable energy resource. |
It is a non-renewable energy resource. |
2. |
It is a fuel mostly used for cooking at homes and lighting purposes. |
It is used in all major industries. |
3. |
It can be formed in less time. |
It takes millions of years for Natural gas to get formed. |
(iii) Ferrous and non – ferrous minerals
S. no. |
Ferrous Minerals |
Non – Ferrous Minerals |
1. |
These minerals have Iron (Fe) as one of the main components. |
These minerals do not have Iron (Fe) as its main component. |
2. |
They get corroded easily. |
They do not possess the property of corrosion. |
3. |
They show magnetic properties. |
They do not show magnetic properties. |
4. |
Example: Manganese, Iron |
Example: Copper, Gold |
(iv) Metallic and non – metallic minerals
S. no. |
Metallic Minerals |
Non – metallic minerals |
1. |
They can be melted to form new products. |
They cannot be melted to form new products. |
2. |
They are lustrous. |
They are not lustrous. |
3. |
Example: Gold, Iron |
Example: Sulphur, Hydrogen |