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WorksheetsCOMBUSTION AND FLAME-2
Total questions: 27
Worksheet time: 14mins
An ideal fuel is cheap, readily available, easily combustible and easy to transport. It has high calorific value. It does not produce gases or residues that pollute the environment. Based on the above statements which of the following is closest to being an ideal fuel?
Compressed Natural Gas (CNG)
Kerosene
Petrol
Coal
When a cracker is ignited, a sudden reaction takes place with the evolution of heat, light and sound. Identify the type of combustion?
Explosion
Random combustion
Rapid combustion
Spontaneous combustion
Which is the hottest part in the flame of the candle
Yellow
Wax part
Black
Blue
Good fuel is
Readily available
Cheap
Burn easily in air
All of these
Ideal fuel has ____________ calorific value
Zero
Low
Moderate
High
The least hot zone of a candle flame is
non-lumious zone
luminous
dark zone
blue zone at the base of the wick
Moderately hot zone in a candle flame
outer zone
middle zone
innermost zone
wax candle
which occurs rapidly and produce heat and light?
When water is poured over burning wood, the fire goes off. This is because
temperature of wood decreases
temperature of water goes up
molecules of water reacts with oxygen present in the flame
the flame vapourises
Fire is extinguished by
removing all combustible substance
cutting off supply of air
cooling the burning substance
all the these
Identify the luminous zone in the given picture
A
C
B
None
The substance which ________ during burning give flames,
Heats
Vaporise
Boils
Melts
Combustion is a
Chemical process
Physical process
Both of these processes
None of these processes
Burning of charcoal in a closed room will produce
Carbon dioxide
Nitrogen
Chlorine
Carbon monoxide
Which part of a flame does a goldsmith blow for melting gold and silver?
(a)
Burning of LPG is an example of
Spontaneous
Rapid
Explosion
None
The amount of heat produced on burning one kilogram of fuel completely is called its (a) '
An increase in the average temperature of the earth’s atmosphere, especially a sustained increase that causes climatic changes, is termed as (a) ""
Why does a piece of paper burn with yellow flame?
Very high ignition temperature
Inadequate supply of oxygen
Very low ignition temperature
All of the above
Coal burns with ______
(a) Flame
(b) Only glow
(c) Both flame and glow
(d) None of these
Water cannot be used as a fire extinguisher to put out.
(a) Burning charcoal
(b) Burning oil
(c) Burning paper
(d) Burning cloth
CNG and LPG are the examples of
(a) Solid fuels
(b) Liquid fuels
(c) Gaseous fuels
(d) They are not fuels
The least hot zone of a candle flame is
non-lumious zone
luminous
dark zone
blue zone at the base of the wick
