Question: 1. What are the advantages of using CNG and LPG as fuels?
Answer: Following are the advantages of using CNG and LPG as fuels:
(a) They are more efficient
(b) They can be easily transported; either in cylinders or through pipelines
(c) They are less polluting than other fossil fuels
Question: 2. Name the petroleum product used for surfacing of roads.
Answer: BitumenFig: Liquid bitumen.Question: 3. Describe how coal is formed from dead vegetation. What is this process called?
Answer: Dead remains of plants got buried under the earth millions of years ago. Due to intense heat and pressure inside the earth they got converted into coal. The process of conversion of dead remains of plants into coal is called carbonization.
Fig: Formation of CoalQuestion: 4. Fill in the blanks:
(a) Fossil fuels are …………, ………… and ……………..
Answer: Coal, Petroleum and Natural gas
(b) Process of separation of different constituents from petroleum is called ……………..
(c) Least polluting fuel for vehicle is ………………
Question: 5. Tick True/False against the following statements:
(a) Fossil fuels can be made in the laboratory. ( F)
(b) CNG is more polluting fuel than petrol. (F)
(c) Coke is almost pure form of carbon. (T)
(d) Coal tar is a mixture of various substances. (T)
(e) Kerosene is not a fossil fuel. (F)
Question: 6. Explain why fossil fuels are exhaustible natural resources.
Answer: It takes millions of years for the formation of fossil fuels. The rate at which we are using them is very fast compared to the rate of their formation. Due to this, fossil fuels are exhaustible in nature.
Question: 7. Describe characteristics and uses of coke.
Answer: Coke is a type of coal. It is a tough, porous and black substance. It is almost pure form of carbon. Coke burns much cleaner than coal and provides more energy for comparable mass. It is used in manufacture of steel and in extraction of many minerals.
Fig: Coal and Coke
Question: 8. Explain the process of formation of petroleum.
Answer: The organisms which lived in the sea got buried at the bottom of oceans. Over a period of time, their dead bodies were covered with sediments. Intense pressure and heat under the earth’s layers transformed these organisms into petroleum.
Fig: Petrol formation.
Question: 9. The following Table shows the total power shortage in India from 1991– 1997. Show the data in the form of a graph. Plot shortage percentage for the years on the Y-axis and the year on the X-axis.