Social Science STD 8 Chapter 10: Minerals and Power Resources : Exercises

Social Science STD 8 Chapter 10: Minerals and Power Resources : Exercises

1. Write the answers of the following questions in one sentence:

  1. 1. Write the names of the three minerals of your daily use.

    Iron, Aluminium, and Copper are three minerals of daily use.

  2. 2. Where are ores of metallic minerals usually found?

    Ores of metallic minerals are usually found in large layers of igneous and metamorphic rocks.

  3. 3. Where are the geothermal power plants located in India?

    In India, geothermal power plants are located at Manikaran in Himachal Pradesh and Puga Ghati in Ladakh.

  4. 4. Which products are obtained by processing petroleum?

    Products like diesel, petrol, kerosene, wax, plastics, and lubricants are obtained by processing petroleum.

  5. 5. Where are the hot springs located in Gujarat?

    Hot springs are located in Lasundra, Unai, Tuva, and Tulsishyam in Gujarat.

2. Answer the following questions:

  1. 1. Why is crude oil called 'black gold'?

    Crude oil is called 'black gold' because of its immense commercial value. It is a very valuable resource from which various useful substances like diesel, petrol, kerosene, wax, plastics, and lubricants are processed. No part of it is useless, making it a highly profitable resource.

  2. 2. Write the measures by which we can save energy.

    To save energy, we must increase the use of non-conventional energy sources like water, solar, wind, and biogas. We should also reduce the use of non-renewable resources such as coal and petroleum by exploring alternatives like solar electricity and CNG. It is also important to reuse metal scrap like iron, copper, and aluminum. These measures help in conserving precious resources for the future and maintaining environmental quality.

  3. 3. Where is coal found in Gujarat?

    In Gujarat, lignite coal is found in various areas, including Kutch, Bharuch, Mehsana, Bhavnagar, and Surat. Specifically, there are estimated reserves of lignite coal in Pandhro in Kutch, Tadkeshwar in Surat, Rajpardi in Bharuch, and Thordi in Bhavnagar.

  4. 4. The use of non-conventional energy sources will have to be increased in the future.' - Explain the statement.

    Non-conventional energy sources must be increasingly used in the future because conventional sources like coal and crude oil are limited and will eventually be exhausted. The consumption rate of these non-renewable resources far exceeds their formation rate. Furthermore, burning fossil fuels releases toxic pollutants, which is a major concern. Non-conventional sources such as solar, wind, and tidal energy are renewable and pollution-free, making them a necessary alternative to ensure sustainable development and a clean environment for future generations.

  5. 5. How can it be said that it is wise to reduce the use of fossil fuels in the future?

    Reducing the use of fossil fuels is wise because these are non-renewable resources that take thousands of years to form, and their reserves are depleting at an alarming rate. The extensive consumption of these fuels is causing the Earth's temperature to rise and releases toxic pollutants, which harm the environment. By reducing our reliance on fossil fuels and shifting to non-conventional and renewable sources like solar and wind energy, we can conserve these limited resources and mitigate environmental damage, ensuring a better future.

3. Choose the correct option from the following options and write the correct answer:

  1. 1. Which of the following is not a characteristic of a mineral?

    They are inaccessible.

  2. 2. Match the following pairs:

    (a-4), (b-5), (c-2), (d-1), (e-3)

  3. 3. World's largest geothermal power plant is located in which country?

    U.S.A.

4. Fill in the blanks:

  1. 1. ........ minerals are used in metallurgy industry.

    Fluorspar

  2. 2. ........ state receives the maximum solar energy in the country.

    Gujarat

  3. 3. ........ and ........ areas in Gujarat have natural gas reserves.

    Ankleshwar and Gandhar

  4. 4. ........ mineral is used for plating galvanized sheets.

    Zinc

  5. 5. Lignite coal is found in ........ of Kutch district.

    Pandhro

5. Explain the terms:

  1. 1. Minerals

    Minerals are organic and inorganic substances that, under the influence of heat and pressure, acquire a specific chemical composition. They are found in the Earth's interior in the form of ores, which are then refined to obtain pure minerals. Minerals are naturally formed over thousands of years and are a backbone of a nation's economy.

  2. 2. Geothermal energy

    Geothermal energy is the energy obtained by harnessing the steam produced from the Earth's interior due to natural geological processes. The temperature deep inside the Earth increases, and this heat sometimes emerges as hot springs on the surface. This heat can be used to generate power, and this type of energy is considered pollution-free and eco-friendly.

  3. 3. Tidal energy

    Tidal energy is a form of energy generated from the movement of tides. This energy is harnessed by building dams near narrow sea openings. During high tide, the tidal energy is used to turn a turbine installed in the dam, which generates electricity. This is an inexhaustible and pollution-free source of energy.

  4. 4. Biogas

    Biogas is a gaseous fuel produced from the decomposition of organic waste like dead plants, animal dung, and kitchen waste. The decomposition process releases methane gas, which is combustible and serves as an excellent fuel for cooking and generating electricity. This process also generates a large amount of organic manure, making biogas production beneficial for both energy and fertilizer. It is a cheap and easy-to-use resource, with Gujarat ranking second in its production in India.

6. Distinguish between:

  1. 1. Conventional Energy Sources - Non-conventional Energy Sources

    Conventional Sources: These are energy sources that have been in common use for a long time. They are often exhaustible and can cause environmental pollution. Examples include firewood and fossil fuels like coal and crude oil.

    Non-conventional Sources: These are energy sources that are not in common use but are becoming increasingly important. They are typically renewable and pollution-free. Examples include solar energy, wind energy, tidal energy, and biogas.

  2. 2. Biogas - Natural Gas

    Biogas: This is a gaseous fuel created from the decomposition of organic materials like animal dung and plant residues. It is an environmentally friendly and renewable resource that also produces organic manure.

    Natural Gas: This is a fossil fuel found with petroleum deposits, trapped between layers of rocks in the Earth's crust. It is a non-renewable resource and can cause pollution when burned, although it is cleaner than other fossil fuels.

  3. 3. Metallic Minerals - Non-metallic Minerals

    Metallic Minerals: These minerals contain metals in their raw form. Metals are hard substances that conduct heat and electricity, and they have lustre. They can be molded into different shapes without breaking. Examples include gold, iron, and copper.

    Non-metallic Minerals: These minerals do not contain metals. They are often found in sedimentary rocks and break into pieces when struck. Examples include limestone, mica, gypsum, and fossil fuels like coal and petroleum.

7. Write short notes on:

  1. 1. Importance of mineral resources

    Minerals are of great importance as they serve as the foundation for economic growth and development. They provide essential raw materials to various industries, making a nation prosperous. Minerals are considered the backbone of the national economy. For instance, iron ore is used to make everything from pins to large machines, ships, and bridges. Other minerals like copper, aluminum, and mica are crucial for electrical equipment, construction, and various other industries.

  2. 2. Measures for mineral conservation

    To conserve minerals, it is important to reduce waste in the mining process, as many non-renewable minerals take thousands of years to form. A key measure is recycling metals like iron, copper, and aluminum, so they can be reused. It is also essential to explore alternatives to scarce minerals. We should increase the use of non-conventional and renewable energy sources like solar, wind, and biogas to reduce our dependence on non-renewable fossil fuels.

  3. 3. Solar energy

    The sun is the primary source of energy, and its energy can be trapped using solar cells to produce electricity. This energy is particularly beneficial for tropical countries with abundant sunshine. Solar energy is an inexhaustible and pollution-free source. It is used in solar water heaters, cookers, and dryers, as well as for community lighting and traffic signals. Gujarat is a leading state in India in solar energy development, with projects like the 590 MW Solar Park at Charanka village.

  4. 4. Biogas

    Biogas is a gaseous fuel produced from the decomposition of organic waste like dead plants, animal dung, and kitchen waste. The decomposition process releases methane gas, which is combustible and serves as an excellent fuel for cooking and generating electricity. This process also generates a large amount of organic manure, making biogas production beneficial for both energy and fertilizer. It is a cheap and easy-to-use resource, with Gujarat ranking second in its production in India.