MEDIUM
Earn 100

Have you ever tried burning a piece of paper or wood or coal, a small rock or a pebble?

Important Questions on Chemical Changes and Reactions

EASY
Science>Chemistry>Chemical Changes and Reactions>Combustion and Respiration
State any two conditions required for combustion.
MEDIUM
Science>Chemistry>Chemical Changes and Reactions>Combustion and Respiration
Name two substances having low ignition temperatures and two having high ignition temperatures.
EASY
Science>Chemistry>Chemical Changes and Reactions>Combustion and Respiration
Nitrogen supports combustion.
EASY
Science>Chemistry>Chemical Changes and Reactions>Combustion and Respiration
What are combustible substances? Name three combustible substances.
EASY
Science>Chemistry>Chemical Changes and Reactions>Combustion and Respiration
Blisters and ulcers occur in the case of _____.
MEDIUM
Science>Chemistry>Chemical Changes and Reactions>Combustion and Respiration
Why does a goldsmith blow air into the kerosene lamp flame with a blow-pipe?
EASY
Science>Chemistry>Chemical Changes and Reactions>Combustion and Respiration
List conditions under which combustion can take place.
MEDIUM
Science>Chemistry>Chemical Changes and Reactions>Combustion and Respiration
Why do you have to use paper or kerosene oil to start fire in wood or coal?
MEDIUM
Science>Chemistry>Chemical Changes and Reactions>Combustion and Respiration
Can the process of rusting be called combustion? Give reason for your answer.
EASY
Science>Chemistry>Chemical Changes and Reactions>Combustion and Respiration
It is difficult to burn a heap of green leaves but dry leaves catch fire easily. Explain. 
MEDIUM
Science>Chemistry>Chemical Changes and Reactions>Combustion and Respiration
What are the conditions necessary for combustion to take place?
EASY
Science>Chemistry>Chemical Changes and Reactions>Combustion and Respiration
_____ is the technique to put out a fire on our clothes. (Give proper indentation) [Stop, drop and roll/ Run and jump in water]
HARD
Science>Chemistry>Chemical Changes and Reactions>Combustion and Respiration
How will you show that air is necessary for combustion?
EASY
Science>Chemistry>Chemical Changes and Reactions>Combustion and Respiration
The temperature of the substance should be lowered below the _____ temperature. (room / kindling)
MEDIUM
Science>Chemistry>Chemical Changes and Reactions>Combustion and Respiration
What are fuels? Name any two common fuels.
EASY
Science>Chemistry>Chemical Changes and Reactions>Combustion and Respiration
What are non-combustible Substances? Name three non-combustible substances.
MEDIUM
Science>Chemistry>Chemical Changes and Reactions>Combustion and Respiration
Explain why, when a burning candle is covered with an inverted gas jar, the candle gets extinguished after some time.
EASY
Science>Chemistry>Chemical Changes and Reactions>Combustion and Respiration
Which one is a supporter of combustion?
MEDIUM
Science>Chemistry>Chemical Changes and Reactions>Combustion and Respiration
Can you burn a piece of wood by burning a lighted matchstick near it? Explain.
MEDIUM
Science>Chemistry>Chemical Changes and Reactions>Combustion and Respiration
If you see a person whose clothes are on fire, how will you extinguish the fire? Give reason for your answer.