Burning
1. Presence of Fuel
Burning begins only if something that can burn is present.Examples: paper, wood, kerosene, LPG.
2. Oxygen from Air
The fuel must have oxygen around it.Without oxygen, no burning can start.
3. Heating the Fuel
The fuel must be heated to its ignition temperature.This is the minimum temperature at which the fuel starts burning.
This heat may come from:
A matchstick
A spark
Friction
Another flame
4. Ignition (Start of Burning)
Once the fuel reaches ignition temperature, it reacts rapidly with oxygen.This point is called ignition.
5. Combustion Reaction Begins
The chemical reaction starts:
Fuel + Oxygen → New substances + Heat + LightThis stage is the burning process itself.
6. Fire Appears
Burning produces:
Heat
Light
Flame (in some cases)
Smoke
Hot gases
All these together form fire.
Fire is the visible result of combustion.
7. Flame Formation (If Applicable)
A flame appears when:
The fuel changes into hot gases
These gases glow because of high temperature
Flame = glowing gasFire = whole burning process
Not all fires produce flames (example: red-hot charcoal).
8. Production of Gases
During burning, several gases are released:
Carbon dioxide (CO₂)
Water vapour
Carbon monoxide (CO) (if oxygen is low)
Other gases depending on the fuel
These gases rise into the air.
9. Smoke Formation
If burning is incomplete, some parts of the fuel do not burn fully.These form:
Soot
Tiny particles
Unburnt carbon
These mix with hot air and appear as smoke.
10. Formation of Ash
After burning is finished, the leftover solid part is ash.Ash is made of:
Minerals
Non-burnable parts of the fuel
Ash proves that the fuel has turned into new substances, meaning a chemical change has occurred.
11. Type of Chemical Reaction
Burning is an:
Exothermic Oxidation Reaction (Combustion)
Exothermic → releases heat & light
Oxidation → reacts with oxygen
This is why burning becomes hotter and brighter.