Science Class 8 - Coal And-Petroleum Notes

Coal and Petroleum

Welcome to the chapter on Coal and Petroleum for Class 8. In this chapter, you will learn about two important natural resources—coal and petroleum. You will understand how they are formed, their uses, and why we need to use them wisely. By the end of this chapter, you will know the importance of conserving these resources for the future.

Introduction

Coal and petroleum are fossil fuels. They are formed from the remains of plants and animals buried under the earth millions of years ago. These resources are very useful but limited, so we must use them carefully.

Formation of Coal

Coal is formed from dead plants that got buried under soil and rocks. Over millions of years, heat and pressure turned these plants into coal.

• Coal is black and hard.
• It is mainly made of carbon.

Types of Coal

• Peat: Soft and contains less carbon.
• Lignite: Brown coal, more carbon than peat.
• Bituminous: Harder, used for making coke.
• Anthracite: Hardest and purest form of coal.

Uses of Coal

• Used as fuel in homes and industries.
• Used to generate electricity in thermal power plants.
• Used to make coke, which is used in steel making.
• Used to make coal tar and coal gas.

Formation of Petroleum

Petroleum is formed from dead sea animals and plants buried under the sea. Over millions of years, heat and pressure turned them into petroleum.

• Petroleum is a thick, dark liquid.
• It is found deep under the ground or sea.

Refining of Petroleum

Petroleum is separated into useful products by a process called refining. This is done in oil refineries.

• Petrol, diesel, kerosene, and LPG are obtained from petroleum.
• Other products include lubricating oil, paraffin wax, and asphalt.

Uses of Petroleum

• Petrol and diesel are used as fuels in vehicles.
• Kerosene is used for cooking and lighting.
• LPG is used for cooking.
• Lubricants are used in machines.
• Petrochemicals are used to make plastics, paints, and medicines.

Natural Gas

Natural gas is found along with petroleum. It is a clean fuel and used for cooking, heating, and generating electricity.

Conservation of Fossil Fuels

• Coal and petroleum are limited and non-renewable.
• Use public transport and save fuel.
• Switch off engines when not needed.
• Use alternative sources like solar and wind energy.

Environmental Impact

• Burning coal and petroleum causes air pollution.
• It leads to global warming and acid rain.
• We must use these resources wisely to protect our environment.

Fun Activity: Energy Detective!

Make a list of things at home that use coal, petroleum, or natural gas. Find out how you can save energy!

Summary

• Coal and petroleum are important fossil fuels.
• They are formed over millions of years from dead plants and animals.
• They have many uses but are limited and cause pollution.
• We must conserve them and use clean energy sources.

Practice Questions

1. How is coal formed?
2. Name two products obtained from petroleum.
3. Why should we conserve fossil fuels?
4. What is the process of separating petroleum called?
5. Mention one harmful effect of burning coal and petroleum.

Challenge Yourself

• List three ways to save fuel at home or school.
• Find out about one alternative energy source and write about it.

Did You Know?

• India has large coal reserves but imports much of its petroleum.
• Natural gas is the cleanest fossil fuel.

Glossary

• Fossil Fuel: Fuel formed from dead plants and animals over millions of years.
• Refining: The process of separating petroleum into useful products.
• Non-renewable: Cannot be replaced quickly; limited in amount.
• Pollution: Making air, water, or land dirty and harmful.

Answers to Practice Questions

1. Coal is formed from dead plants buried under soil and rocks, changed by heat and pressure over millions of years.
2. Petrol, diesel, kerosene, LPG (any two).
3. Because they are limited and cause pollution when used.
4. Refining.
5. Air pollution or global warming.

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Use coal and petroleum wisely and help protect our planet for the future!