Coal and Petroleum Class 8 Extra Questions Science Chapter 5
Coal and Petroleum Class 8 Extra Questions Very Short Answer Questions
Question 1.
Name some renewable sources of energy.
Answer:
Water, wind, solar.
Question 2.
Give some examples of fossil fuels.
Answer:
Coal, petroleum, natural gas.
Question 3.
Name the elements present in coal.
Answer:
Carbon, oxygen and sulphur.
Question 4.
Which are the two main techniques of mining?
Answer:
Surface mining and underground mining.
Question 5.
List four varieties of coal.
Answer:
Peat, lignite, bituminous, anthracite.
Question 6.
Name the process of conversion of wood into coal.
Answer:
Carbonisation
Question 7.
Mention the temperature at which destructive distillation is done.
Answer:
1000°C
Question 8.
When the crude oil is referred to be ‘sweet’?
Answer:
If the sulphur content is low.
Question 9.
Name the process of conversion of kerogen into gaseous hydrocarbons.
Answer:
Catagenesis
Question 10.
Name the country which is the leading producer of petroleum.
Answer:
Saudi Arabia
Question 11.
Name the gas that occurs over petroleum in reservoirs deep inside the earth.
Answer:
Natural gas
Question 12.
Expand PCRA.
Answer:
Petroleum Conservation Research Association.
Question 13.
Name two fractions of petroleum which are used as fuel.
Answer:
Petrol and diesel
Question 14.
What kind of pollution is caused by the burning of fossil fuels?
Answer:
Air pollution
Question 15.
Write the full form of LPG.
Answer:
Liquefied Petroleum Gas.
Question l6.
Which gas is produced when coal is burnt in air?
Answer:
Carbon dioxide
Question 17.
Can we use all our natural resources forever?
Answer:
No
Question 18.
What is the purest form of carbon?
Answer:
Coke
Question 19.
Where and when was the first oil well drilled?
Answer:
Pennsylvania, USA in 1859.
Question 20.
Name the places where natural gas is found in our country.
Answer:
Tripura, Rajasthan, Krishna Godavari Delta, Maharashtra, etc.
Coal and Petroleum Class 8 Extra Questions Short Answer Questions
Question 1.
What is fuel?
Answer:
Anything that burns to produce energy in an efficient manner is called a fuel.
Question 2.
Define fossil fuels. Give examples.
Answer:
Natural fuels that are made up by burial of living organisms under deep down the earth for over a long period of time, are called fossil fuels.
For example, coal, petroleum, natural gas.
Question 3.
What is coal? Write its two uses.
Answer:
Coal is a hard, black combustible substance that mainly contains carbon.
Uses:
- It is used as a fuel in homes and industry.
- It is used as a fuel at Thermal Power Plants for generating electricity.
Question 4.
Give a brief description about peat.
Answer:
Peat is the most inferior and softest form of coal. Its carbon content is very low. It has a large amount of moisture and is not much suitable to be used as fuel. Its carbon content is 20 – 25%.
Question 5.
Name three constituents of petroleum and write their uses also.
Answer:
The three constituents of petroleum are:
- petrol
- paraffin wax
- diesel
Uses:
- Petrol: It is used as a motor fuel and for dry cleaning.
- Paraffin wax: It is used for making ointments, candles, vaseline, etc.
- Diesel: It is used as a fuel for heavy motor vehicles and electric generators.
Question 6.
Explain about coal tar.
Answer:
It is produced when the gases are evolved due to heating of coal in water. It is a black-coloured, thick, viscous liquid. It has a pungent smell. It is itself a mixture of many compounds. We can get benzene, toluene, napthalene, phenol, etc., from coal tar.
Question 7.
Name two products that you obtain from the destructive distillation of coal. What is the residue left in’ this process? Give one main use of this residue.
Answer:
The two important products obtained from the destructive distillation of coal are: Coal gas and coal tar. The residue left in this process is coke. Coke is used mainly as a reducing agent in the extraction of metals.
Question 8.
Where do we get coal and how is it formed?
Answer:
We get coal deep in the earth’s crust in coal mines. It is formed by the slow decomposition of dead trees and other vegetable matter buried deep under the earth’s crust under high pressure and temperature.
Question 9.
Define the term ‘petrochemicals’.
Answer:
Petrochemicals are the substances obtained from petroleum and natural gas. They are used in the manufacture of detergents, fibres, polythene, etc.
Question 10.
What is CNG? What are its uses?
Answer:
CNG is short form of Compressed Natural Gas. Natural gas is stored under high pressure as CNG. CNG is used for power generation. It is now being used as a fuel for transport vehicles because it is less polluting. It is a cleaner fuel.
Coal and Petroleum Class 8 Extra Questions Long Answer Questions
Question 1.
Explain about the varieties of coal.
Answer:
Depending upon the amount of carbon content, coal may be of four types:
- Peat: This is the most inferior and softest form of coal. Its carbon content is very low. It has a large amount of moisture and is not much suitable to be used as fuel.
- Lignite: Lignite is comparatively harder than peat, but still is very soft. Its carbon content is more than that of peat.
- Bituminous: Its carbon content is higher, as it is free from moisture and other impurities.
- Anthracite: This is the highest grade coal. This is also known as hard coal. It has maximum amount of carbon. It produces a very little smoke.
Question 2.
The burning of fossil fuels causes air pollution. Explain.
Answer:
The burning of fossil fuels causes a lot of air pollution.
The burning of coal produces gases like carbon dioxide, carbon monoxide, sulphur dioxide, etc., which can lead to undesirable changes in climate due to increase greenhouse effect.
The major air pollutants produced by the burning of petrol in automobiles are carbon monoxide, sulphur dioxide, unbumt hydrocarbons, etc. These pollutants are harmful for human beings and living organisms which causes breathing problems and skin diseases.
Question 3.
Write a short note on petroleum.
Answer:
Petroleum is the liquid form of fuel. It is also known as crude oil and found trapped between the layers of impervious rocks under the ground. It is a natural resource, which formed by the dead plants and animals in the sea. It is a dark coloured viscous liquid and like all other oils, it is lighter than water. It is a mixture of different hydrocarbons. It undergoes fractional distillation to yield petrol, kerosene, diesel and other chemicals used in manufacture of plastics.
Question 4.
How is the energy useful to us? Explain.
Answer:
We need energy in almost every field of our life. Without energy our life is impossible. Some of the uses of energy are:
- We need energy of fuels to generate electricity and to run vehicles.
- We need energy to run our electrical appliances like refrigerator, TV, radio, computer, etc.
- We need energy at construction sites to construct houses, buildings, etc.
- We need energy to cook our food and other domestic use.
- We need energy (petrochemicals) for manufacturing fibres, plastics, paints, cosmetics, etc.
- All the factories, industries, agricultural devices depend on power supply to run the machines.
Question 5.
List the steps to conserve the resources.
Answer:
As we know, we all are dependent on the resources. But we should keep in mind that resources are limited in nature. If we misuse it, our future generation will have no resources. This is an alarming situation.
We can take following steps:
- We shbuld cook our food on low flame.
- Devices that consume less energy like CFLs and LED lights should be preferred.
- We should take care not to waste electricity.
- We should cover our cooking vessels while cooking.
- Instead of use of individual vehicles, use of public transport should be encouraged.
- Solar or tidal energy should be developed and encouraged.
- Dams should be use to generate electricity instead of burning coal or petroleum.
- Public awareness programmes should be conducted.
Coal and Petroleum Class 8 Extra Questions Higher Order Thinking Skills
Question 1.
You are provided with a mixture of petroleum and water. How will you separate the two?
Answer:
Allow to stand the mixture of petroleum and water undisturbed for some time. The top layer will be consisted of petroleum which can be separated from water by decantation.
Question 2.
Differentiate between coke and coal.
Answer:
| Coke | Coal |
| (i) It is an amorphous form of carbon. | (i) It is a non-crystalline form of carbon. |
| (ii) It is obtained by heating soft coal in absence or limited supply of air. | (ii) It is obtained by the decay of vegetation which existed millions of years ago. |
Question 3.
None of the fuels is clean fuel. Comment.
Answer:
On burning, every fuel releases atleast C02 which causes greenhouse effect. Thus none of the fuels are clean.
Question 4.
Can forests help reduce the pollution caused by burning of fossil fuels? How?
Answer:
Not all, but yes it reduces some of the pollution like carbon dioxide emitted during burning of fossil fuels.
Question 5.
What other source of energy may be used to drive vehicles?
Answer:
Biodiesel, ethanol, solar energy.
Coal and Petroleum Class 8 Extra Questions Value-Based Questions
Question 1.
Radhey prefers to go to school by pooling car. On other occasions he like to opt for public transport rather than private transport. For short distances, he walks or uses bicycle.
(a) What are the benefits of carpooling?
(b) Which mean of transport do you think is best for short distances?
(c) How on our end we can reduce the consumption of fossil fuels?
(d) What values of Radhey are shown here?
Answer:
(a)
- Cost effective
- Reduces pollution
- Reduces traffic on roads
- Saves fossil fuels
(b) Bicycle
(c)
- By reducing use of plastics as these are products of fossil fuels.
- By consuming electrical energy judiciously as most of the electricity comes from burning coal.
- By carpooling. As car uses petrol or diesel—a form of fossil fuel.
- Switching engine off at red lights.
(d) Radhey is eco-friendly, environmentally conscious and works judiciously.
Question 2.
There was an essay-writing competition on ‘How to Reduce your Carbon Footprint’ in Satish’s school. Satish enquired his best on this topic to his elders and searched internet. He got the first prize in the competition.
(a) What do you understand by the term ‘Carbon Footprint’?
(b) Suggest ways to reduce your carbon footprint.
(c) What values of Satish are shown here?
Answer:
(a) The total amount of greenhouse gases produced by an individual, organisation or event is known as ‘Carbon Footprint’.
(b)
- Follow 3R’s, i.e., – reduce, reuse and recycle.
- Use public transport and carpool.
- Avoid traffic.
- Plant trees.
- Use energy efficient appliances.
(c) Satish is inquisitive, intelligent, hard working and sincere boy.
Activities and Projects
Question 1.
Get an outline map of India. Mark the places in the map where coal, petroleum and natural gas are found. Show the places where petroleum refineries are situated.
Answer:
Question 2.
Choose any five families of your neighbourhood. Enquire whether their energy consumption (coal, gas, electricity, petrol, kerosene) has increased or decreased in the last five years. Enquire also about the measures they adopt to conserve energy.
Answer:
Do it yourself.
Question 3.
Find out the location of major thermal power plants in India. What could be the reasons for their being located at those places?
Answer:
Major thermal power plants in India are located in Uttar Pradesh, Gujarat, West Bengal, Odisha, Chhattisgarh and Madhya Pradesh. The reason for their being located at those places is the presence of majority of coal mines nearer to them.
I. Multiple Choice Questions (MCQs)
Choose the correct option.
Question 1.
Which of the following is a renewable source of energy?
(a) Coal
(b) Petroleum
(c) Water
(d) Natural gas
Question 2.
Which of the following is a non-renewable source of energy?
(a) Water
(b) Coal
(c) Soil
(d) Sun
Question 3.
Plastic is a
(a) natural material
(b) man-made material
(c) both (a) & (b)
(d) none of these
Question 4.
Fossil fuels are
(a) coal
(b) petroleum
(c) natural gas
(d) all of these
Question 5.
The word ‘coal’ is derived from the old English term
(a) col
(b) coke
(c) coco
(d) none of these
Question 6.
Which of the following minerals is present in coal?
(a) Hydrogen
(b) Oxygen
(c) Sulphur
(d) All of these
Question 7.
Naphthalene balls are used as
(a) mosquito repellant
(b) moth repellant
(c) snake repellant
(d) bee repellant
Question 8.
How much percentage of carbon is present in bituminous?
(a) 20 – 25%
(b) 25 – 35%
(c) 65 – 85%
(d) 98%
Question 9.
The process of conversion of wood into coal is called
(a) carbonisation
(b) catagenesis
(c) carboniferous
(d) none of these
Question 10.
Petroleum is also known as
(a)coke
(b) black gold
(c) tar
(d) none of these
Question 11.
The brown variety of coal is
(a) lignite
(b) peat
(c) anthracite
(d) none of these
Question 12.
The major constituent of natural gas is/are
(a) butane
(b) methane
(c) hydrogen
(d) ethane
Question 13.
The product obtained by destructive distillation of coal is
(a) coal tar
(b) coke
(c) coal gas
(d) all of these
Question 14.
The petroleum product which is not used as fuel is
(a) petrol
(b) kerosene
(c) diesel
(d) petroleum jelly
Question 15.
Main constituent of LPG is
(a) methane
(b) butane
(c) ethane
(d) propane
Question 16.
A natural gas stored under high pressure is called
(a) CNG
(b) LPG
(c) KLG
(d) PNP
Question 17.
Name the petroleum product used for surfacing of road.
(a) Peat
(b) Bitumen
(c) Lignite
(d) Anthracite
Question 18.
The mining of oil under sea is termed as
(a) distillation
(b) carbonisation
(c) shore mining
(d) destructive distillation
Question 19.
Which is the best type of coal?
(a) Lignite
(b) Anthracite
(c) Bituminous
(d) peat
Question 20.
Petroleum is separated by using the difference in
(a) ignition temperatures
(b) melting points
(c) freezing points
(d) boiling points
Answer:
1. (c)
2. (b)
3. (b)
4. (d)
5. (a)
6. (d)
7. (b)
8. (c)
9. (a)
10. (b)
11. (a)
12. (b)
13. (d)
14. (d)
15. (b)
16. (a)
17. (b)
18. (c)
19. (b)
20. (d)
II. Fill in the Blanks
Fill in the blanks with suitable word/s.
1. Resources which get replenished by natural processes in a certain period of time is called ___________.
2. ___________ is a mixture of various constituents such as lubricating oil, paraffin wax, etc.
3. ll the things that are required to fulfil one’s need are called ___________.
4. Anything that burns to produce energy is called a ___________.
5. ___________ is a black-coloured hard substance that mainly contains carbon.
6. The time period taken to complete the process of carbonisation is called ___________.
7. ___________ is the most inferior and softest form of coal.
8. The least polluting fuel for vehicle is ___________.
9. The major fossil fuels are ___________ and ___________.
10. The major component of CNG is ___________.
11. Destructive distillation of coal is done at ___________.
12. Petroleum is a mixture of different ___________.
13. ___________ is another name for petroleum.
14. Devices that consume less energy are ___________ and ___________ lights.
15. Forests are ___________ natural resources.
16. Petra means ___________ and oleum means ___________.
17. ___________ is the leading producer of crude oil.
18. When heated in air, coal burns and produces mainly ___________ gas.
19. We should use ___________ instead of individual vehicles.
20. Separation of different constituents of petroleum is called ___________.
Answer:
1. renewable resources
2. Petroleum
3. resources
4. fuel
5. Coal
6. carboniferous age
7. Peat
8. CNG
9. coal, petroleum
10. methane
11. 1000°C
12. hydrocarbons
13. Black gold
14. CFL, LED
15. exhaustible
16. rock, oil
17. Saudi Arabia
18. carbon dioxide
19. carpools
20. refining of petroleum
III. Match the following
Match the items given in column I suitably with those given in column II.
Answer:
1. (c)
2. (a)
3. (b)
4. (f)
5. (g)
6. (d)
7. (e)
8. (h)
9. (j)
10. (i)
IV. True or False
State whether the given statements are true or false.
1. Coal is a renewable source of energy.
2. Coal is a solid fossil fuel.
3. Coke is almost a pure form of carbon.
4. CNG is more polluting than petrol.
5. 40% of electricity generation depends on coal.
6. Carbon content of lignite is 25-35%.
7. Fossil fuels are inexhaustible natural resources.
8. We get napthalene ball from coal tar.
9. The time period take to complete carbonisation is called carboniferous age.
10. Peat is the hardest grade coal.
11. Petroleum is also known as ‘black gold.’
12. 30% of paraffins is present in petroleum.
13. Petroleum can be mixed with water.
14. Natural gas is transported through pipelines.
15. Kerosene is not a fossil fuel.
Answer:
1. False
2. True
3. True
4. False
5. True
6. True
7. False
8. True
9. True
10. False
11. True
12. True
13. False
14. True
15. False