Q1Multiple choice
Various materials which are obtained from nature are called natural resources. Which of the following is not a natural resource?
- (a)minerals
- (b)water
- (c)soil
- (d)plastic
Show answer
(d) plastic
Chapter 5 – Coal And Petroleum
Class 8 Science · 35 questions · 35 with answers
Questions
Q2Multiple choice
Air is a natural resource and cannot be exhausted by human activities. It is known as inexhaustible natural resource. Which of the following is another inexhaustible natural resource?
- (a)coal
- (b)petroleum
- (c)sun-light
- (d)minerals
Show answer
(c) sun-light
Q3Multiple choice
Which of the following is a pair of exhaustible natural resources.
- (a)coal and soil
- (b)air and sun-light
- (c)water and petroleum
- (d)wild life and minerals
Show answer
(d) wild life and minerals
Q4Multiple choice
Coal is processed in industries to get some useful products. Which of the following is not obtained from coal?
- (a)coke
- (b)coal tar
- (c)coal gas
- (d)CNG
Show answer
(d) CNG
Q5Multiple choice
Exhaustible natural resources are:
- (a)unlimited in quantity.
- (b)not dependent on nature.
- (c)limited in quantity.
- (d)not exhausted by human activities.
Show answer
(c) limited in quantity.
Q6Multiple choice
Fossil fuels are obtained from:
- (a)remains of non-living materials.
- (b)dead remains of birds only.
- (c)dead remains of insects only.
- (d)dead remains of living organisms.
Show answer
(d) dead remains of living organisms.
Q7Multiple choice
Coal is formed from the remains of
- (a)vegetation only
- (b)animals only
- (c)both vegetation and animals
- (d)neither vegetation nor animals C OAL AND PETROLEUM 25
Show answer
(a) vegetation only
Q8Multiple choice
Which substance is formed by the carbonisation of dead vegetation?.
- (a)coal
- (b)coke
- (c)coal gas
- (d)coal tar
Show answer
(a) coal
Q9Multiple choice
Naphthalene balls are obtained from coal tar and are used as
- (a)mosquito repellant
- (b)honey bee repellant
- (c)moth repellant
- (d)snake repellant
Show answer
(c) moth repellant
Q10Multiple choice
Which of the following is not a constituent of petroleum?
- (a)paraffin wax
- (b)lubricating oil
- (c)petrol
- (d)coke
Show answer
(d) coke
Q11Multiple choice
Petroleum was formed from organisms:
- (a)living on the land
- (b)living on the plants
- (c)living in the sea
- (d)living on the rocks
Show answer
(c) living in the sea
Q12Multiple choice
Choose the correct statement from the following:
- (a)It is difficult to transport natural gas through pipes.
- (b)The disadvantage of natural gas is that it can not be used directly for burning in homes.
- (c)Natural gas is stored under high pressure as compressed natural gas.
- (d)Natural gas cannot be used for power generation.
Show answer
(c) Natural gas is stored under high pressure as compressed natural gas.
Q13Very short answer
You are provided with a mixture of petroleum and water. Can you suggest a method to separate the two?
Show answer
Decantation
Q14Very short answer
What does CNG stand for and why is it considered to be a better fuel than petrol?
Show answer
CNG stands for Compressed Natural Gas. It is considered to be a better fuel because it is less polluting.
Q15Very short answer
Name the petroleum product used as fuel for stoves, lamps and jet aircrafts.
Show answer
Kerosene is used as fuel for stoves, lamps and jet aircrafts.
Q16Multiple choice
Fill in the blanks in the following sentences.
- (a)Coal is one of the ________ used to cook food.
- (b)When heated in air, coal burns and produces mainly ________ gas.
- (c)Coal tar is a black, thick ________ with an ________ smell.
- (d)Petroleum, ________ and ________ are fossil fuels. (e) Forests and coal are ________ natural resources. 26 E XEMPLAR PROBLEMS
Show answer
(a) Coal is one of the ________ used to cook food.
(d) Petroleum, ________ and ________ are fossil fuels. (e) Forests and coal are ________ natural resources. 26 E XEMPLAR PROBLEMS
(b) When heated in air, coal burns and produces mainly ________ gas.
(c) Coal tar is a black, thick ________ with an ________ smell.
Q17Multiple choice
The underlined words in the following sentences have been jumbled up. Write them in their correct form.
- (a)Loca is obtained from mines.
- (b)Umpetlore is a fossil fuel.
- (c)Rineryfe is a place where various fractions of peroleum are separated.
- (d)Keenrose is a fuel used in jet crafts. (e) Nutsgilh is an example of inexhaustible natural resources.
Show answer
(a) Loca is obtained from mines.
(b) Umpetlore is a fossil fuel.
(c) Rineryfe is a place where various fractions of peroleum are separated.
(d) Keenrose is a fuel used in jet crafts. (e) Nutsgilh is an example of inexhaustible natural resources.
Q18Multiple choice
Fill in the blanks.
- (a)The slow process of conversion of dead vegetation into coal is called__________.
- (b)Coal and petroleum are formed from the dead remains of organisms and are known as __________.
- (c)The black thick liquid with __________ smell is known as coal tar.
- (d)During the processing of coal to get coke, coal tar and __________ are also obtained. (e) The process of separating the various constituents of petroleum is known as __________. (f) Excessive burning of fossil fuels is a major cause of __________.
Show answer
(a) The slow process of conversion of dead vegetation into coal is called__________.
(b) Coal and petroleum are formed from the dead remains of organisms and are known as __________.
(c) The black thick liquid with __________ smell is known as coal tar.
(d) During the processing of coal to get coke, coal tar and __________ are also obtained. (e) The process of separating the various constituents of petroleum is known as __________. (f) Excessive burning of fossil fuels is a major cause of __________.
Q19Multiple choice
Write True/False against the following statements.
- (a)Oxygen in air is an exhaustible natural resource.
- (b)Resources which are present in unlimited quantity in nature are called exhaustible natural resources.
- (c)Wildlife is an exhaustible natural resource.
- (d)Under high temperature and pressure, dead plants get slowly converted to coal. (e) CNG is less polluting fuel than petrol and diesel.
Show answer
(a) Oxygen in air is an exhaustible natural resource.
(b) Resources which are present in unlimited quantity in nature are called exhaustible natural resources.
(c) Wildlife is an exhaustible natural resource.
(d) Under high temperature and pressure, dead plants get slowly converted to coal. (e) CNG is less polluting fuel than petrol and diesel.
Q20Short answer
Sunlight and air are inexhaustible natural resources. Comment.
Show answer
These resources are present in unlimited quantity in nature and are not likely to be exhausted by human activities.
Q21Short answer
Some natural resources are given in a box. Classify them into the exhaustible and inexhaustible natural resources. air, coal, natural gas, sunlight, petroleum, minerals, forests, oxygen. C OAL AND PETROLEUM 27
Show answer
Exhaustible natural resources are coal, natural gas, petroleum, minerals, forests. Inexhaustible natural resources are air, sunlight, oxygen. 122 E XEMPLAR PROBLEMS
Q22Short answer
Write two important uses of coke.
Show answer
It is used for extraction of many metals and also for the manufacture of steel.
Q23Short answer
Write the characteristics and some important uses of coal.
Show answer
Coal is black in colour and hard as stone. It is one of the fuels used to cook food. Earlier it was used in railway engines to produce steam to run the engine. It is used as fuel in thermal power plants to produce electricity and in various other industries.
Q24Short answer
Look at Fig. 5.1 where petroleum and natural gas deposits are shown. Why do we find oil layer above water layer? Fig. 5.1
This question refers to a figure in the original PDF.
Show answer
Hint: Oil is lighter than water hence floats over it.
Q25Fill in the blanks
Fill in the blanks and complete the story. About 300 million years ago the earth had dense ________ in low lying wetland areas. Due to natural processes, like ______, these forests got burried under the ________. As more ________ deposited over them, they were compressed. The ________ also rose as they sank deeper and deeper. Under high ________ and high ________, dead plants got slowly converted into coal.
Show answer
forests, floods, soil, soil, temperature, pressure, temperature.
Q26Multiple choice
Match the items given in Column I with the items of Column II. Column I Column II (a) Used for road surfacing
- (i)Black gold (b) Natural gas
- (ii)Vaseline and candles (c) Petroleum
- (iii)Bitumen (d) Paraffin wax
- (iv)CNG
Show answer
(i) Black gold (b) Natural gas
(iii) Bitumen (d) Paraffin wax
(ii) Vaseline and candles (c) Petroleum
(iv) CNG
Q28Short answer
E XEMPLAR PROBLEMS
Show answer
It takes a very long time for the formation of fossil fuels. It also requires specific conditions and it doesn’t happen quite often. Therefore, their limited stock will last only for a few hundred years.
Q29Long answer
We read in newspapers that burning of fuels is a major cause of global warming. Explain why.
Show answer
Hint: It is related to global warming due to formation of carbon dioxide and some other gases.
Q30Long answer
While driving what are the tips we must follow to save petrol/ diesel/natural gas?
Show answer
• Ensure correct tyre pressure. • Ensure regular maintenance of the vehicle. • Drive at a constant and moderate speed. • Switch off the engine at traffic lights or at a place where you have to wait. ANSWERS 123
Q31Long answer
Imagine that all the exhaustible natural resources are exhausted by human activities. Do you think survival of living beings would be possible.? If yes, why?, If not, why not?
Show answer
This is an open ended question. Let children imagine and write.
Q32Long answer
Why petrol is exhaustible natural resource, whereas sunlight is not? Explain.
Show answer
Hint: Sunlight is present in unlimited quantity in nature whereas it takes millions of years to form petrol from dead remains of organisms.
Q33Long answer
Write some important uses of the various constituents of petroleum.
Show answer
• Petroleum gas in liquid form (LPG) — used as fuel for home and industry. • Petrol — used as fuel for automobile and aviation. • Kerosene — used as fuel for stoves, lamps and for jet aircrafts. • Diesel — used as fuel for heavy motor vehicles, electric generators. • Lubricating oil — used for lubrication • Praffin wax — used in ointments, candles, vaseline etc. • Bitumen — used in paints and road surfacing.
Q34Long answer
Coal reserves are said to be enough to last for another hundred years. Do you think we need to worry in such case? Why or why not?
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Open ended question. Let children write their views.
Q35Long answer
What steps would you suggest for the judicious use of fossil fuels?
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Open ended questions. Let children write their ideas.
Q36Long answer
Complete the crossword Fig. 5.2 with the help of the clues: Fig. 5.2 C OAL AND PETROLEUM 29 Across 1. Fuels obtained form dead remains of living organisms. (6,5) 2. A process by which the various constituents of petroleum are separated. (8) 3. A porous black substance obtained form coal. (4) 4. Another name for motor fuel. (6) Down 5. The substance obtained by carbonisation. (4) 6. Fuel for heavy motor vehicles. (6) 7. A petroleum product used for road surfacing. (7) 8. Dead remains of sea animals got converted into it. (9)
This question refers to a figure in the original PDF.
Show answer
124 E XEMPLAR PROBLEMS