MEDIUM
8th CBSE
IMPORTANT
Earn 100

Follow the clues and solve the terms you have learned.

Across:

1. A portable device that discharges a jet of water, carbon dioxide gas, or other material for putting out small fires (4,12)

3. A very fast combustion reaction in which a large amount of heat, light, and sound is produced.

Down: 

1. A hot, luminous mixture of gases undergoing combustion.

2. The amount of heat energy produced on the complete combustion of 1kg of fuel (4,10)

4. The lowest temperature at which a substance catches fire and starts burning (8,11)

5. Rain which contains small amounts of acids formed from acidic gases such as sulphur dioxide and nitrogen oxides present in polluted air (4,4)

6. A material that is burnt to produce heat energy.

7. A fuel that fulfils most of the requirements for a particular use (5,4)

Question Image

Important Questions on Combustion and Flame

MEDIUM
8th CBSE
IMPORTANT
Fill in the blank with the correct options from the box.
Every fuel must be heated to its _____ before it can start burning.
Carbon dioxide Carbon monoxide Ignition temperature Water Low
Kilojoule per kg (kj/kg) Nuclear Spontaneous Hotter Blue, yellow
HARD
8th CBSE
IMPORTANT

Fill in the blank with the correct options from the box.
Fire caused by oil cannot be extinguished with _____.

Carbon dioxide Carbon monoxide Ignition temperature Water Low
Kilojoule per kg kj/kg Nuclear Spontaneous Hotter Blue, yellow
MEDIUM
8th CBSE
IMPORTANT

Fill in the blanks with the correct options from the box.

 Forest fire is an example of _____combustion.

Carbon dioxide Carbon monoxide Ignition temperature Water Low
Kilojoule per kg (kj/kg) Nuclear Spontaneous Hotter Blue, yellow
MEDIUM
8th CBSE
IMPORTANT
Fill in the blank with the correct options from the box.
Substances with _____ ignition temperature catch fire easily.
Carbon dioxide Carbon monoxide Ignition temperature Water Low
Kilojoule per kg kJ/kg Nuclear Spontaneous Hotter Blue, yellow
MEDIUM
8th CBSE
IMPORTANT

Fill in the blanks with the correct options from the box. Calorific value is measured in _____.

Carbon dioxide Carbon monoxide Ignition temperature Water Low
Kilojoule per kg Nuclear Spontaneous Hotter Blue, yellow
EASY
8th CBSE
IMPORTANT

Fill in the blank with the correct options from the box.
In the sun, heat and light are produced due to _____ reactions.

Carbon dioxide Carbon monoxide Ignition temperature Water Low
Kilojoule per kg (kj/kg) Nuclear Spontaneous Hotter Blue, yellow
EASY
8th CBSE
IMPORTANT
Fill in the blank with the correct options from the box.
_____ is used to extinguish the fire that involves electrical equipment.
Carbon dioxide Carbon monoxide Ignition temperature Water Low
Kilojoule per kg (kJ/kg) Nuclear Spontaneous Hotter Blue, yellow
MEDIUM
8th CBSE
IMPORTANT
Fill in the blank with the correct options from the box.
The non-luminous zone is _____ than the luminous zone.
Carbon dioxide Carbon monoxide Ignition temperature Water Low
Kilojoule per kg (kj/kg) Nuclear Spontaneous Hotter Blue, yellow