Parts of Flame
Picture showing the burning of the candle
The parts of the flame are mentioned below :
- Innermost zone of unburnt wax.
- Middle zone consisting of partially burnt carbon particles.
- Moderately hot zone.
- Hottest zone of completely burnt carbon particles blue in color. It is also called non- luminous zone or the zone of complete combustion.
Understand the meaning of Flame
Activity to understand the meaning of flame :
Take glass tube hold it carefully with a pair of tongs and introduce its one end into the dark zone of a non â€“flickering candle flame Bring a lighted matchstick near the other end of the glass tube. Observe the other end of the glass tube, do you see any flame, Find out the reason for the appearance of the flame. The wax that melts quickly around the wick vaporizes passes through the glass tube reaches the other end and burns with a flame as shown in the diagram.
The picture shows that vapors of wax catches fire when a lighted match stick is brought near it, thus it is concluded that combustible substances that vaporizes and catches fire is called flame. The substances that vaporizes quickly on heating gives flame. For Example, kerosene oil and molten wax rise through the wick and are vaporized during burning and form flames. Charcoal, on the other hand, does not vaporizes and so does not produce a flame.
Activities to understand that different parts of the flame differ in their temperature:
Take a glass plate of 3 cm * 4 cm of length and width hold it with a pair of tongs and show it in to the luminous zone of the flame for about 10 seconds. Remove it from the flame and observe.
Take a long copper wire of 10 cm length , hold it with a pair tongs and introduce it just in to the flame for 30 seconds and observe the changes that takes place to the portion of the copper wire just outside the flame. Record your observations in the form of tabular column.
|Activity 1||Formation of circular blackish ring||Due to the deposition of unburnt carbon particles.||The part of the flame is the luminous zone which is less hot|
|Activity 2||Copper wire becomes red hot||Due to complete combustion maximum heat is supplied to the copper wire.||This part of the flame is non luminous which is more hot.|
Formation of Circular Blackish Ring
Copper Wire becomes Red Hot