TEXTBOOK QUESTIONS AND THEIR ANSWERS Q.1.

Transcription

1 5 COAL AND PETROLEUM TEXTBOOK QUESTIONS AND THEIR ANSWERS Q.1. Make a list of various materials used by us in daily life and classify them as natural and man-made. Natural Man-made Ans. Natural Water Sunlight Air Soil Coal Man-made Plastic Clothes Refrigerator Car Machine 1

2 Minerals Fruits Petroleum Natural gas Bed Bicycle Paper Biscuits Q.2. Can we use all our natural resources forever? Ans. No, we cannot use all our natural resources forever. Some other natural resources like sunlight, air and soil are inexhaustible, which are present in unlimited quantity, so, we use them forever. Some natural resources like coal, petroleum, natural gas and forest are exhaustible, the amount of these resources in nature is limited. So, we cannot use them forever. Q.3. Can air, water and soil be exhausted by human activities? Ans. Air, water and soil are present in unlimited quantity in nature and are not exhausted by human activities. So, these are Inexhaustible Natural Resources. Q.4. Is water a limitless resource? 2

3 Ans. Yes, water is a limitless resource and it is maintained by the water-cycle. But increasing population, growing irrigation requirements and mismanagement make the water scare. Q.5. Where do we get coal from and how is it formed? Ans. We get coal from the remains of the dead plants and animals. So, it is also called fossil fuel. Millions of years ago many dead animals and plants got buried under the layers of earth. They got compressed due to more soil deposited over them. So, the temperature under the earth started raising due to high pressure. Finally, the dead plants and animals under high temperature and pressure got converted into coal. Q.6. Can coal, petroleum and natural gas be prepared in the laboratory from dead organisms? Ans. No, the formation of coal, petroleum and natural gas from dead organisms is very slow process. It requires the millions of years to get converted into fuel. So, the condition for the formation of petroleum and natural gas cannot be created in the laboratory. Q.7. What are the advantages of using CNG and LPG as fuels? Ans. CNG (Compressed Natural Gas) and LPG (Liquefied Petroleum Gas) are very important fossil fuel because :- 3

4 1. It is easy to transport through pipes. 2. It is used for power generation. 3. A non polluting fuel for vehicles. 4. These can be used directly for burning in homes and factories where it can be supplied through pipes. 5. These can also be used as a starting material for manufacturing a number of chemicals and fertilizers. 6. These are cleaner fuels. 7. These are low cost fuels. 8. These are available easily. Q.8. Name the petroleum product used for surfacing of roads? Ans. Bitumen and coaltar are used for surfacing of roads. Q.9. Describe how coal is formed from dead vegetation. What is this process called? Ans. Millions of years ago many dead animals and plants get buried under the layers of earth. They got compressed due to more soil deposited over them. So, the temperature under the earth started raising due to high pressure. Finally, the dead plants 4

5 and animals under high temperature and pressure got converted into coal. This process is called carbonization. Q.10. Fill in the blanks : (a) Fossil fuels are, and. (b) Process of separation of different constituents from petroleum is called. (c) Least polluting fuel for vehicle is. Ans. (a) Coal, petroleum, natural gas (b) Refining (c) CNG Q.11. Tick True/False against the following statements: (a) Fossil fuels can be made in the laboratory. (b) CNG is more polluting fuel than petrol. (c) Coke is almost pure form of carbon. (d) Coaltar is a mixture of various substances. (e) Kerosene is not a fossil fuel. 5

6 Ans. a. False b. False c. True d. True e. False Q.12. Explain why fossil fuels are exhaustible natural resources. Ans. Fossil fuels are made by the decomposition of the dead remains of living organisms. The amount of fossil fuel in nature is limited. It can be exhausted by human activities. So, fossil fuels are exhaustible natural resources. Q.13. Describe characteristics and uses of coke. Ans. Coke is obtained by heating soft coal in the absence of air. Coke is a tough, porous and black substance. It is almost pure form of carbon. Coke is used in the manufacturing of steel and in the extraction of many metals. Q.14. Explain the process of formation of petroleum. 6

7 Ans. Petroleum is a fossil fuel. It is formed by decomposition of the dead bodies of the living organisms buried beneath the earth. Due to some natural calamities like earthquake or volcano, innumerable living organisms (plants and animals) got burried beneath the earth. Due to heat and pressure, they started getting decomposed and got converted into liquid and gas form. In this way, petroleum oil and petroleum gas are formed. Q.15. The following Table shows the total power shortage in India from Show the data in the form of a graph. Plot shortage percentage for the year on the Y-axis and the year on the X-axis. S.No. Year Shortage (%) Ans. 7

8 Scale Along x axis 1 unit = 1 year Along y axis 1 unit = 2% 8