combustion flame and fuel

The substances can easily be burned in the presence of air is called combustible sub

Ex: coal , petroloam, LPG, paper ,matchsticketc

The substances that cannot catch fire in the presence of air is called combustible substances

Ex: sand, rock,water,glass

a combustible substance - For the combustion , you need the presence of a combustible substances

a supporter of combustion- elements that support the combustion of a substance . EX: oxygen

heating it to its ignition temperature

Substances that have a low ignition temperature and can catch fire easily is called inflammable substances .

The substances that vaporize on heating produce flame while those substances that do not vaporize don't produce flame .

• nature of the substance burnt
• availability of oxygen
• temperature

• non -luminous - It is the outermost zone that is very hot. Complete combustion , cannot be seen.
• luminous zone- is the middle zone it is luminous and can be seen it is partial combustion, yellow colour
• Dark Zone- it is the inner most part of the candle and , Here no combustion combustion takes place , dark blue color