Here we are providing Class 8 Science Objective Chapter – 6 Combustion and Flame because its very important for Class 8 students as we all know that every board exam question has MCQs so that students should practice these questions so that students can get good marks in board. Class 8 Science Objective Chapter – 6 Combustion and Flame is an extremely important and its also a year in which students learn the fundamentals of concepts that help them lay a solid foundation for their higher education. Here we are providing in Class Class 8 Science Objective Chapter – 6 Combustion and Flame Wastewater Story 100+ questions so that students practice more and more. If you want class wise Notes Then Click Here
Class 8 Science Objective Chapter – 6 Combustion and Flame
1.Which of the following fuels is used for running automobiles?
( A ) CNG
( B ) Petrol
( C ) Both ( A ) and (b)
( D ) Wood
Ans – ( C )
2.Which one of the following gases is used in combustion?
( A ) Hydrogen
( B ) Oxygen
( C ) Nitrogen
( D ) Carbon dioxide
Ans – ( B )
3.Magnesium burns to form
( A ) calcium carbonate
( B ) magnesium oxide
( C ) calcium oxide
( D ) magnesium sulphate
Ans – ( B )
4.The burning of LPG is an example of
( A ) rapid combustion
( B ) spontaneous combustion
( C ) slow combustion
( D ) explosion
Ans – ( A )
5.Coal burns to produce
( A ) calcium bicarbonate
( B ) magnesium
( C ) carbon dioxide
( D ) oxygen
Ans – ( C )
6.A temperature at which the substance burns is called
( A ) melting
( B ) boiling temperature
( C ) kindling temperature
( D ) evaporation
Ans – ( C )
7.Name the chemical process in which a substance reacts with oxygen to give out heat.
( A ) Reaction
( B ) Junction
( C ) Combustion
( D ) All of these
Ans – ( C )
8.Which is non-renewable source of energy’?
( A ) Natural gas
( B ) Wind energy
( C ) Tidal energy
( D ) Mechanical energy
Ans – ( A )
9.The substance that undergoes combustion is said to be
( A ) burning
( B ) flame
( C ) charcoal
( D ) combustible
Ans – ( D )
10.Which of the following is not a fossil fuel?
( A ) Coal
( B ) Petroleum
( C ) Natural gas
( D ) Water gas
Ans – ( D )
11.Combustible substances are also known as
( A ) inflammable
( B ) flaming
( C ) illuminous
( D ) non-flammable
Ans – ( A )
12.Which gas helps in the process of combustion?
( A ) Cooking gas
( B ) Nitrogen gas
( C ) Oxygen gas
( D ) Producer gas
Ans – ( C )
13.Which of the following is combustible?
( A ) Stone piece
( B ) Wood
( C ) Glass
( D ) None of these
Ans – ( B )
14.Which zone represents the partial combustion in candle flame?
( A ) Outer zone
( B ) Middle zone
( C ) Inner zone
( D ) Lower zone
Ans – ( B )
15.In the sun, light and heat are produced by
( A ) chemical reactions
( B ) nuclear reactions
( C ) burning reactions
( D ) bunsen burner
Ans – ( B )
16.Lowest temperature at which a substance catches fire is known as
( A ) lowest temperature
( B ) burning temperature
( C ) ignition temperature
( D ) flaming temperature
Ans – ( C )
17.Burning coal in a closed room will produce
( A ) nitrogen oxides
( B ) carbon dioxide
( C ) carbon monoxide
( D ) oxygen
Ans – ( C )
18.Long, long ago, which of the following trees was used to produce matchsticks?
( A ) Mango
( B ) Deodar
( C ) Banyan
( D ) Pine
Ans – ( D )
19.Substances which catch fire are called
( A ) acids
( B ) bases
( C ) combustible
( D ) burners
Ans – ( C )
20.Which chemical is used in the rubbing surface provided for matchsticks?
( A ) Sulphur
( B ) Gold
( C ) Red phosphorus
( D ) White phosphorus
Ans – ( C )
21.Out of these, which is able to control fires?
( A ) NH3
( B ) H2
( C ) CO2
( D ) F2
Ans – ( C )
22.Substances that have very low ignition temperature and can catch fire easily are called
( A ) flammable substances
( B ) inflammable substances
( C ) combustible substances
( D ) all of these
Ans – ( D )
23.Which zone of a flame does a goldsmith use for melting gold and silver ?
( A ) Outer zone
( B ) Middle zone
( C ) Inner zone
( D ) Lower zone
Ans – ( A )
24.Which of the following is an example of inflammable substance?
( A ) Iron
( B ) Glass
( C ) LPG
( D ) Stone
Ans – ( C )
25.Calorific value of a fuel is expressed in
( A ) kilojoule per kilogram
( B ) kilojoule per gram
( C ) joule per milligram
( D ) kilojoule per milligram
Ans – ( A )
26.Which of the following are required essentially for producing fire?
( A ) Glass, coal, water
( B ) Fuel, coal, straw
( C ) Fire, wood, burner
( D ) Fuel, air, heat
Ans – ( D )
27.Which is non-combustible substance?
( A ) Wood
( B ) Paper
( C ) Iron nails
( D ) Straw
Ans – ( C )
28.The most common element used as fire extinguisher is
( A ) CO2
( B ) oxygen
( C ) phosphorus
( D ) NO2
Ans – ( A )
29.Acid rain contains mainly
( A ) oxygen and nitrogen gas
( B ) fluorine and chlorine gas
( C ) magnesium oxide
( D ) nitrogen oxide and sulphur dioxide
Ans – ( D )
30.Baking soda constitutes
( A ) hydrogen chloride
( B ) sodium oxide
( C ) sodium bicarbonate
( D ) oxygen
Ans – ( C )
31.Which of the following fuel produces ash on burning:
( A ) wood
( B ) LPG
( C ) petrol
( D ) diesel
Ans – ( A )
32.LPG means
( A ) Liquefied Petroleum Gas
( B ) Liquefied Petrol Gas
( C ) Liquid Petrol Godown
( D ) Liquid Petroleum Gas
Ans – ( A )
33.The zone of a flame used by goldsmith for melting gold and silver is:
( A ) innermost zone
( B ) middle zone
( C ) outermost zone
( D ) all of these
Ans – ( C )
34.Phosphorus burns at
( A ) room temperature
( B ) 100°C
( C ) cool temperature
( D ) any temperature
Ans – ( A )
35.Can the process of rusting he called combustion ?
( A ) yes
( B ) no
( C ) can’t say
( D ) none of these
Ans – ( A )
36.‘Firework’ is an example of
( A ) rapid combustion
( B ) explosion
( C ) spontaneous combustion
( D ) slow combustion
Ans – ( B )
37.Is heat and light produced by Sun a combustion process?
( A ) yes
( B ) no
( C ) can’t say
( D ) none of these
Ans – ( B )
38.The calorific value of ‘hydrogen’ is
( A ) 50,000 kJ/kg
( B ) 55,000 kJ/kg
( C ) 1,50,000 kJ/kg
( D ) 6,000 kJ/kg
Ans – ( C )
39.Heat and light produced in the sun is by:
( A ) combustion
( B ) nuclear reactions
( C ) burning
( D ) none of these
Ans – ( B )
40.Which of these is a combustible substance?
( A ) Asbestos
( B ) Paper
( C ) Stone
( D ) Sand
Ans – ( B )
41.Ignition temperature is the:
( A ) temperature at which a substance catches fire
( B ) highest temperature at which a substance catches fire
( C ) lowest temperature at which a substance catches fire
( D ) none of these
Ans – ( C )
42.Which of the following is non¬combustible substance?
( A ) Alcohol
( B ) Coal
( C ) Iron
( D ) Wood
Ans – ( C )
43.Which of them can be easily burnt with the help of a matchstick?
( A ) wooden chips
( B ) straw
( C ) wooden log
( D ) all of them
Ans – ( B )
44.Which of the following is an inflammable substance?
( A ) Coal
( B ) Alcohol
( C ) Wood
( D ) Stone
Ans – ( B )
45.A mgtchstjck does not catch fire on its own at room temperature because its:
( A ) ignition temperature is more than room temperature
( B ) ignition temperature is less than room temperature
( C ) ignition temperature is same as room temperature
( D ) none of these
Ans – ( A )
46.A flame has
( A ) one zone
( B ) two zones
( C ) three zones
( D ) four zones
Ans – ( C )
47.Which of the following gas extinguishes fire:
( A ) oxygen
( B ) hydrogen
( C ) carbon dioxide
( D ) nitrogen
Ans – ( C )
48.The outermost zone of flame is in colour.
( A ) blue
( B ) orange
( C ) brown
( D ) dark
Ans – ( A )
49.Combustion that takes place at a very fast rate is called:
( A ) rapid combustion
( B ) spontaneous combustion
( C ) explosion
( D ) none of these
Ans – ( A )
50.Which of the following does not produce flame while burning?
( A ) Wax
( B ) Petrol
( C ) Diesel
( D ) Coal
Ans – ( D )
51.The coldest zone of candle is:
( A ) the middle zone
( B ) the innermost zone
( C ) the outermost zone
( D ) none of these.
Ans – ( B )
52.Combustion is a
( A ) chemical process
( B ) physical process
( C ) both of these
( D ) none of these
Ans – ( A )
53.Smoke contains:
( A ) unburnt carbon particles
( B ) burnt carbon particles
( C ) unburnt sulphur particles
( D ) unburnt lead particles.
Ans – ( B )
54.The lowest temperature at which a substance catches fire is called its
( A ) boiling point
( B ) melting point
( C ) ignition temperature
( D ) critical temperature
Ans – ( C )
55.The colour of the non-luminous zone is:
( A ) white
( B ) yellow
( C ) blue
( D ) black
Ans – ( C )
56.In the presence of water, ignition temperature of paper
( A ) decreases
( B ) increases
( C ) remains constant
( D ) none of these
Ans – ( B )
57. A chemical process in which a substance reacts with oxygen to give off heat is called
( A ) Conduction
( B ) Conjunction
( C ) Combustion
( D ) Confusion
Ans – ( C )
58.Rapid combustion occurs when
( A ) gas bums and produces heat and light
( B ) material suddenly bursts into flames
( C ) there is evolution of heat
( D ) none of these
Ans – ( A )
59. Fuel may be
( A ) Solid only
( B ) Solid,Liquid or gas
( C ) Liquid only
( D ) Gas only
Ans – ( B )
60.Explosion involves the evolution of
( A ) heat
( B ) light
( C ) sound
( D ) all of these
Ans – ( D )
61. The amount of heat energy produced on complete combustion of_____ fuel is called its calorific value.
( A ) 1 litre
( B ) 1 Kg
( C ) 1 milli litre
( D ) 1 gram
Ans – ( B )
62.A substance which vaporises during burning gives
( A ) sound
( B ) flame
( C ) combustion
( D ) none of these
Ans – ( C )
63. The substances which have very low ignition temperature and can easily catch fire with a flame are called
( A ) Inflammable substances
( B ) Flaming substance
( C ) Fire proof substance
( D ) None of the above
Ans – ( A )
64.The most common fire extinguisher is
( A ) water
( B ) carbon dioxide
( C ) oxygen
( D ) hydrogen
Ans – ( A )
65. When we heat water in a paper bowl over a candle, the paper does not catch fire because
( A ) Paper is not inflamable
( B ) Paper gets wet
( C ) Due to water the ignition temperature of paper is not reached
( D ) This is not possible
Ans – ( C )
66.Unburnt carbon particles cause
( A ) stomach infections
( B ) respiratory problems
( C ) brain infections
( D ) throat problems
Ans – ( B )
67. When oil or petrol catches fire, water is not used to extinguish it because
( A ) Water covers oil and oil burns under water layer which may not be noticeable
( B ) Water is heavier than oil / petrol and so remains below the oil layer which continues to burn
( C ) Water get mixed with oil and increases fire
( D ) Water gets evaporated
Ans – ( B )
68.In the Sun, heat and light are produced by
( A ) chemical reactions
( B ) nuclear reactions
( C ) ionic reactions
( D ) none of these
Ans – ( B )
69. In combustion
( A ) Both heat and light is produced
( B ) Only heat is produced
( C ) Only light is produced
( D ) All are correct
Ans – ( A )
70.The head of the safety match contains
( A ) antimony trisulphate
( B ) potassium chlorate
( C ) both ( A ) and (b)
( D ) none of these
Ans – ( C )
71. A person caught fire on clothes is wrapped with blanket because
( A ) The person suddenly feels cold
( B ) To hide the burnt body parts
( C ) The person’s clothes gets burnt
( D ) To reduce air supply and put fire off
Ans – ( D )
72.When a matchstick is struck against the rubbing surface, red phosphorus
( A ) converts into white phosphorus
( B ) reacts with potassium chlorate
( C ) ignites antimony trisulphide
( D ) none of these
Ans – ( A )
73. Ignition temperature is
( A ) The maximum temperature at which a substance catches fire
( B ) The minimum temperature at which a substance catches fire
( C ) The temperature of burning substance
( D ) The temperature in the substance when fire if put off
Ans – ( B )
74.The amount of heat energy produced on complete combustion of 1 kg of a fuel is called its
( A ) combustion value
( B ) calorific value
( C ) ignition value
( D ) none of these
Ans – ( B )
