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1. What are the advantages of using CNG and LPG as fuels?
Ans: Following are the advantages of using CNG and LPG as fuels:
2. Name the petroleum product used for surfacing of roads.
Ans: Bitumen is the petroleum product used for surfacing of roads.
3. Describe how coal is formed from dead vegetation. What is this process called?
Ans: When the plants and animals are died, they are buried under the layer of soil. Under high pressure and temperature, they are slowly converted into coal. However, it took millions of year for this process. This process is called carbonization.
4. Fill in the blanks.
(a) Fossil fuels are coal, petroleum and natural gas.
(b) Process of separation of different constituents from petroleum is called refining.
(c) Least polluting fuel for vehicle is CNG.
5. Tick True/False against the following statements.
(a) Fossil fuels can be made in the laboratory. (T/F)
Ans: False
(b) CNG is more polluting fuel than petrol. (T/F)
Ans: False
(c) Coke is almost pure form of carbon. (T/F)
Ans: True
(d) Coal tar is a mixture of various substances. (T/F)
Ans: True
(e) Kerosene is not a fossil fuel. (T/F)
Ans: False
6. Explain why fossil fuels are exhaustible natural resources.
Ans: Fossil fuels such as coal and petroleum are exhaustible resources because they are vanished with one use and it took millions of years for their formation.
7. Describe characteristics and uses of coke.
Ans: It is a black, tough and porous material. It is the pure form of carbon, which is used in the manufacturing of steel and extraction of various metals.
8. Explain the process of formation of petroleum.
Ans: Petroleum is formed under the sea from the dead bodies of sea animals that were buried millions of years ago. Under high pressure and temperature they form petroleum. Petroleum is also called crude oil and it is used to obtained petrol, diesel, kerosene, LPG etc.