Question:
Anu wants to boil water quickly in a test tube. On observing the j different zones of the flame, she is not able to decide which zone of the
flame will be best for boiling water quickly. Help her in this activity.
Solution:
Anu should keep her test tube in the outermost zone or non-luminous zone of the flame because it is the hottest zone of a flame and has more
temperature.
In the outer zone of a flame, complete combustion of the fuel takes place because there is plenty of air around it so, water in a test tube will boil
quickly in this zone.