Combustion and Flame
Important notes
Combustion:
Definition: Combustion is a chemical process in which a substance reacts with
oxygen (from the air) and releases energy in the form of heat and light. This
process is commonly called burning.
Types of Combustion:
1. Complete Combustion: Occurs when oxygen is sufficient. The products are
carbon dioxide (CO₂) and water vapor (H₂O). Example: Burning of methane
in oxygen.
2. Incomplete Combustion: Occurs when there is insufficient oxygen. This
results in the formation of carbon monoxide (CO), soot, or other incomplete
products. Example: Burning of wood in a limited air supply.
Conditions for Combustion:
1. Presence of a Combustible Substance: A substance that can burn, like wood,
coal, oil, or gas.
2. Oxygen Supply: Oxygen is required for combustion to take place.
3. Heat or Activation Energy: A certain amount of heat is needed to start the
combustion process. This is called the ignition temperature.
Ignition Temperature: The minimum temperature at which a substance starts
burning is known as its ignition temperature.
Flame:
Definition: A flame is the visible, gaseous part of a fire. It is produced when a
substance undergoes combustion and produces light and heat.
Parts of a Flame:
1. Outer Zone (Blue Flame): This is the hottest part of the flame, where
complete combustion occurs. In this zone, oxygen is abundant.
2. Inner Zone (Yellow Flame): This part is cooler and usually seen when
combustion is incomplete. The yellow colour is due to the presence of
carbon particles (soot) that are heated and glow.
3. Luminous Zone: The part of the flame that emits light, often seen as yellow
or orange. It occurs when there is incomplete combustion.
Types of Flames:
1. Blue Flame: Indication of complete combustion. Example: A gas stove flame.
Important notes
Combustion:
Definition: Combustion is a chemical process in which a substance reacts with
oxygen (from the air) and releases energy in the form of heat and light. This
process is commonly called burning.
Types of Combustion:
1. Complete Combustion: Occurs when oxygen is sufficient. The products are
carbon dioxide (CO₂) and water vapor (H₂O). Example: Burning of methane
in oxygen.
2. Incomplete Combustion: Occurs when there is insufficient oxygen. This
results in the formation of carbon monoxide (CO), soot, or other incomplete
products. Example: Burning of wood in a limited air supply.
Conditions for Combustion:
1. Presence of a Combustible Substance: A substance that can burn, like wood,
coal, oil, or gas.
2. Oxygen Supply: Oxygen is required for combustion to take place.
3. Heat or Activation Energy: A certain amount of heat is needed to start the
combustion process. This is called the ignition temperature.
Ignition Temperature: The minimum temperature at which a substance starts
burning is known as its ignition temperature.
Flame:
Definition: A flame is the visible, gaseous part of a fire. It is produced when a
substance undergoes combustion and produces light and heat.
Parts of a Flame:
1. Outer Zone (Blue Flame): This is the hottest part of the flame, where
complete combustion occurs. In this zone, oxygen is abundant.
2. Inner Zone (Yellow Flame): This part is cooler and usually seen when
combustion is incomplete. The yellow colour is due to the presence of
carbon particles (soot) that are heated and glow.
3. Luminous Zone: The part of the flame that emits light, often seen as yellow
or orange. It occurs when there is incomplete combustion.
Types of Flames:
1. Blue Flame: Indication of complete combustion. Example: A gas stove flame.
