Coal and Petroleum (NCERT Solutions, Class 8)

Exercise

(1) What are the advantages of using CNG and LPG as fuels?

Ans- Advantages of using CNG and LPG as fuels are

(a) It is easy to transport CNG via pipes.

(b) CNG and LPG are good for environment because they are less polluting environment.

(2)Name the petroleum product used for surfacing of roads.

Ans- Coal tar is the petroleum product used for surfacing of roads. Now a days, bitumen is using for surfacing the roads.

(3) Describe how coal is formed from dead vegetation. What is this process called?

Ans- The dense forest of low lying wetland areas got buried under the earth as a result of flood or natural activities. These forests were compressed by the more soil deposits over them and temperature also increases as these sank deeper and deeper. These dead plants converted to coal due to high pressure and high temperature. Therefore, coal is also called fossil fuel. The process of conversion of dead vegetation in to carbon is called carbonisation.

(4) 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) 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 statement.

(a) Fossil fuels can be made in the laboratory. (T/F)

(b) CNG is more polluting fuel than petrol. (T/F)

(c) Coke is almost pure form of carbon. (T/F)

(d) Coal tar is a mixture of various substances. (T/F)

(e) Kerosene is not a fossil fuel. (T/F)

Ans-

(a) Fossil fuels can be made in the laboratory. (T/F ])

(b) CNG is more polluting fuel than petrol. (T/F[ )

(c) Coke is almost pure form of carbon. (T[ /F)

(d) Coal tar is a mixture of various substances. (T[ /F)

(e) Kerosene is not a fossil fuel. (T/F[ )

(6) Explain why fossil fuels are exhaustible natural resources.

Ans-

The fossil fuels are limited in nature because they need millions of years to convert dead organisms into fuel. The fuel obtained from exhaustible resource will be last for few hundreds year.

(7)Describe characteristics and uses of coke.

Ans-

Characteristics and uses of the coke-

(a) It is a tough, porous and black substance.

(b) It is an almost pure form of carbon.

(c) It is used in the manufacture of steel and in the extraction of many metals.

(8)Explain the process of formation of petroleum.

Ans- Petroleum is formed from the dead organisms of sea. The bodies of these organisms settled at the bottom of sea. The layers of sand and clay covered these bodies. These bodies converted into the petroleum and natural gas in the presence of high pressure and high temperature and in the absence of air. The whole process took millions of year to complete.

(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 on the Y – axis and the year on the X – axis.( Note:- Question is typed as in NCERT books but according to given table years should be from 2004 to 2010)