RBSE Class 8 Science Important Questions Chapter 5 Coal and Petroleum

Rajasthan Board RBSE Class 8 Science Important Questions Chapter 5 Coal and Petroleum Questions and Answers.

RBSE Class 8 Science Chapter 5 Important Questions Coal and Petroleum

Objective Questions

Question 1.    
Inexhaustible natural resources is
(a) Sunlight    
(b) Coal
(c) Natural gas    
(d) Petroleum
Answer:
(a) Sunlight

Question 2.    
Which of the following is fossil fuel?
(a) Coal    
(b) Petroleum
(c) Natural gas 
(d) All of the above
Answer:
(d) All of the above

Question 3.    
The slow process of conversion of dead vegetation into coal is called
(a) Oxidation    
(b) Carbonisation
(c) Reduction    
(d) Hydrogenation
Answer:
(b) Carbonisation

Question 4.    
Naphthalene balls can be prepared from
(a) Coal tar    
(b) Coal
(c) Coke    
(d) Coal gas
Answer:
(a) Coal tar

Question 5.    
PCRA is related to
(a) Good Education
(b) Saving petrol/diesel
(c) Running of vehicles
(d) Refining of petroleum
Answer
(b) Saving petrol/diesel

Fill in the blanks 
1. ................ fuel is an exhaustible resource.
Aswer:
Fossil

2. ................ is a black thick liquid with unpleasant smell.
Answer:
Coal tar

3. Petroleum is a dark coloured ................
Answer:
oily liquid

4. The world's first oil well was drilled in ................ , America.
Answer:
Pennsylvania.

True/False

Tick True/False against the following statements.
1. Coal is not a fossil fuel.
Answer:
False

2. Coke is tough, porous and black substance.
Answer:
True

3. Coal Tar is a black, thick, liquid with pleasant smell.
Answer:
False

4. Kerosene oil is used as fuel for stove, lamp and jet aircrafts.
Answer:
True

5. The conversion of dead animals into fuel is very fast.
Answer:
False

6. India has vast reserves of natural gas. 
Answer:
True

Match the words given in 'Column-A' with 'Column-B'

Question 1. 

Column-A	Column-B
(i) Petrol	(a) Road construction
(ii) Bitumen	(b) Vaseline
(iii) Paraffin wax	(c) Fuel for jet aircraft
(iv) Kerosene oil	(d) Fuel for motor vehicles

Answer:

Column-A	Column-B
(i) Petrol	(d) Fuel for motor vehicles
(ii) Bitumen	(a) Road construction
(iii) Paraffin wax	(b) Vaseline
(iv) Kerosene oil	(c) Fuel for jet aircraft

Question  2.    

Column-A	Column-B
(i) Coal	(a) Thick black liquid
(ii) Coke	(b) Porous black
(iii) Coaltar	(c) Dark oily liquid
(iv) Petroleum	(d) Hard as rock

Answer:

Column-A	Column-B
(i) Coal	(d) Hard as rock
(ii) Coke	(b) Porous black
(iii) Coaltar	(a) Thick black liquid
(iv) Petroleum	(c) Dark oily liquid

Question 3.

Column-A	Column-B
(i) London	(a) Natural gas
(ii) Pennsylvania	(b) First oil well
(iii) Assam	(c) Petroleum
(iv) Krishna Godavari delta	(d) Coal gas

Answer:

Column-A	Column-B
(i) London	(d) Coal gas
(ii) Pennsylvania	(b) First oil well
(iii) Assam	(c) Petroleum
(iv) Krishna Godavari delta	(a) Natural gas

Very Short Answer Type Questions

Question 1. 
What is meant by inexhaustible natural resources?
Answer:
The resources which are present in unlimited quantity in nature and are not likely to be exhausted by human activities are called in-exhaustible natural resources.

Question 2. 
What is the meaning of refining?
Answer:
The process of separating the various constituents/fractions of petroleum is known as refining.

Question 3. 
What is the name given to petroleum due to its great commercial importance?
Answer:
'Black gold'.

Question 4. 
What is the complete name of CNG? 
Answer:
Compressed Natural Gas.

Question 5. 
Write the name the petroleum gas which is used in homes?
Answer:
LPG (Liquified Petroleum Gas).

Question 6. 
Write the names of two fossil fuels. 
Answer:

• Coal 
• Petroleum.

Question 7. 
Where are natural gas reserves present in our country?
Answer:
In our country, natural gas has been found in Tripura, Rajasthan, Maharashtra and in the Krishna Godavari delta.

Question 8. 
What is the meaning of PCRA?
Answer:
PCRA is the short form of Petroleum Conservation Research Association.

Short Answer Type Questions

Question 1. 
Write the names of two products obtained by coal processing and give one use of each product.
Answer:
Products obtained by coal processing and their use:

1. Coke: Coke is used in the industrial preparation of steel.
2. Coal Tar: Coal Tar is used in the formation of synthetic colour.

Question 2. 
In how many classes natural resources present in nature, are classified? Explain each of them.
Answer:
Natural resources present in nature can be broadly classified into two kinds.
1. Inexhaustible Natural Resources:
These resources are present in unlimited quantity in nature and not likely to be exhausted by human activity. Examples are sunlight and air.
2. Exhaustible Natural Resources:
The amount of these resources in nature is limited. They can be exhausted by human activities. Examples of these resources are forests, wildlife, minerals, coal, petroleum, natural gas, etc.

Question 3. 
What is coal tar and its importance? 
Answer:
Coal tar is obtained by the processing of coal. Products obtained from coal tar are used as starting materials for manufacturing various substances used in everyday life and in industry, like synthetic dyes, drugs, explosives, perfumes, plastics, paints, photographic materials, roofing materials, etc. Interestingly, naphthalene balls used to repel moths and other insects are also obtained from coal tar.

Question 4. 
What is petroleum? Which substances are obtained by the refining of it?
Answer:
Petroleum is a dark oily liquid. It has an unpleasant odour. Petroleum gas, petrol, diesel, lubricant oil, paraffin wax, etc. are obtained by the refining of petroleum. The refining of petroleum is carried out in a petroleum refinery.

Question 5. 
What is meant by petrochemicals? Explain.
Answer:
Many useful substances are obtained from petroleum and natural gas. They are termed as 'Petrochemicals'. They are used in the manufacture of detergents, fibres (polyster, nylon, acrylic (etc.), polythene and other man - made plastics. Hydrogen gas obtained from natural gas, is used in the production of fertilisers (urea).

Question 6. 
Being a vigilant citizen, what suggestions will you give to vehicle drivers to save fuel?
Or
Write the complete name of P.C.R.A. and write the four advice to save petrol/diesel given by it.
Or
Write the advices to save petrol/diesel, given by Petroleum Conservation Research Association (PCRA).
Answer:
The complete name of P.C.R.A. is Petroleum Conservation Research Association. The following items of advice are given by it to save petrol/diesel during driving.

1. Drive the vehicle at a constant and moderate speed as far as possible.
2. Switch off the engine of vehicle at traffic lights or at a place where you have to wait.
3. Ensure correct tyre pressure, and
4. Ensure regular maintenance of the vehicle. 

Question 7. 
Fossil fuels must be used only in absolute necessity. Why?
Answer:
Fossil fuels are limited. These are beneficial when we use these fuels in absolute necessity.

1. Less use of them results in better environment.
2. The risk of global warming will be less.
3. They will be available for a longer period of time.

Essay Type Questions

Question 1. 
Represent the various constituents and uses of petroleum in the form of a Table.
Answer:
Various constituents of Petroleum and their uses are as under:

Constituents of petroleum	Uses
1. Petroleum Gas in Liquid form (LPG)	As a fuel for home and industry
2. Petrol	As motor fuel, aviation fuel and solvent for dry cleaning
3. Kerosene	Fuel for stoves, lamps and jet aircrafts
4. Diesel	Fuel for heavy motor vehicles and electric generators
5. Lubricating oil	In the lubrication
6. Paraffin wax	In ointments, candles, vaseline etc.
7. Bitumen	In paints and road surfacing

Question 2. 
Write the various uses of coal. Why the LPG is treated as a better fuel than coal?
Answer:
The important uses of coal are as under:

1. Coal is used as fuel in homes and industries.
2. Coal is used in the formation of coal gas.
3. Coal is used in the formation of coke.
4. Coal is used in the formation of coal tar which is an important source of organic compounds like Benzene, Toluene, Aniline, Naphthalene and Anthracene.
5. Coal is also used in the formation of synthetic petrol and synthetic natural gas.

LPG is treated as a better fuel than coal due to following reasons:

1. LPG bums without smoke so it does not create air pollution.
2. The calorific value of L.P.G is high so it produces excess heat on burning.
3. LPG bums completely and no residues are left.
4. LPG bums easily.
5. No harmful gas is formed by die burning of L.P.G whereas coal bums with excess smoke which creates air pollution.

Calorific value of coal is comparatively low. Coal does not bum completely and leaves large amount of ash. Coal does not bum easily and some harmful gases are also produced during the burning of coal.