combution and flame

1. welcome

2. what is combustion
• It means when the substance reacts with oxygen to give off heat and light
is known as COMBUSTION
• AND also when a substance that burn in air to produce heat and light is
called COMBUSTIBLE SUBSTANCE it is also called as FUEL
•

3. combustion
image

4. CONDITIONS NECESSARY FOR COMBUSTION
• FOR COBUSTION combustible substance is necessary , that thus we know
that when we burn a paper , matchstick , kerosene oil burns quickly but when
we burn straw , wood take a long time to burn . So now we know that
combustible substance must be heated in certain temperature to catch fire.
• and also oxygen is very important gas to burn

5. types of combustion
• RAPID COMBUSTION:
• It means that when any thing produce heat and light rapidly is called RAPID
COMBUSTION.
• SPONTANEOUS COMBUSTION :
• The type of combustion in which a material bursts into flame at room
temperature without the application of heat is known as SPONTANEOUS
COMBUSTION .

6. an experiment on that oxygen is needed for combustion

7. inflammable substances
• In flammable substances means the substance that have very low ignition
temperature and , therefore , can catch the fire easily with a flame is known
as INFLAMABLE SUBSTANCES.
• SOME EXAMPLES ARE:
• PETROL , ALCOHOL , KEROSENE , AND LPG (Liquified petroleum gas)
•

8. EXPLOSION
• We generally light fire crackers on festivals. When a cracker is ignited , it
• explodes as a sudden reaction , takes place giving out heat , light and sound.
• A large amount of gas is libreted .Such a reaction is known as EXPLOSION.

9. image of explosion

10. EXPLAINATION ON EXTINGUSHING OF
FIRE
• You have observed that whenever a fire breaks out a fire brigade arrives with a fire
engine. The water is the most common fire extinguisher . It extinguish the fire in
two ways , One , it cools down the combustible material so that its temperature is
brought below its ignition temperature . It helps fire from preventing the fire from
spreading. Two , water vapours cut off the supply to air to the combustible material
by surrounding it. So the fire extinguished . But water does not extinguishes all types
of fires . It not suitable for fires in involving in electricity. A fire can be controlled
by removing one or more of its conditions . A substance that helps to remove any
one of them is called fire extinguiter .

11. EXTINGUISHING A FIRE

12. what is flame
• A flame is the visible gaseous part of the fire where combustion of fuel
takes place .Not all the substances burn with flame . The substances burn
that vaporizes , burns wit flame
• For example kerosene oil and wax rises through the wick and vaporize
before burning . The vapours burns with flame . On the other hand the
charcoal does not vaporize before burning and so does not produce flame
rather burn with a glow .

13. image of flame

14. thank you