CLASS
VIII SCIENCE
COAL
AND PETROLEUM
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:
Bitumen
3. Describe how coal is formed from
dead vegetation. What is this process called?
Answer:
- Dead remains of plants are buried under the earth millions of years ago. Due
to intense heat and pressure inside the earth they are converted into coal. The
process of conversion of dead remains of plants into coal is called
carbonization.
Question: 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 ……………..
Answer:
Refining
(c) Least polluting fuel for vehicle
is ………………
Answer:
CNG
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 and they are in limited quantity. 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.
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.
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.
Answer:
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