NCERT Class VIII Science Solutions: Chapter 5-Coal and Petroleum Part 3

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Question 7:

Describe characteristics and uses of coke.

Answer:

Coke is a tough porous and black substance. It is produced by destructive distillation of coal.

  • It is an almost pure form of carbon.

  • It is used as domestic as well as an industrial fuel in stoves and furnaces.

  • It is used in the manufacture of steel.

  • It gives little or no smoke.

  • It is used for extraction of metals.

  • It can be used to make fuel gases.

Question 8:

Explain the process of formation of petroleum.

Answer:

Petroleum was formed from organisms living in the sea. As these organisms died, their bodies settled down at the bottom of the sea and got covered with sand and clay. The absence of air, high pressure and high temperature for over millions of years transformed the dead organisms into petroleum and natural gas. The petroleum deposits are usually found mixed with salt water. The petroleum is lighter than salt water, and hence, floats over it.

Image result for petroleum

Mining of Petroleum

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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.

Shortage of petroleum

S. No.

Year

Shortage (%)

1

1991

7.9

2

1992

7.8

3

1993

8.3

4

1994

7.4

5

1995

7.1

6

1996

9.2

7

1997

11.5

Answer:

As showing in images is a Total power shortage in india

Total Power Shortage in India

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