Combustion and Flame

· Combustion: The process of burning a substance in the presence of air (oxygen) and

undergoes a chemical reaction to produce heat and light.

· The substances which burn in air are called combustible.

· Oxygen (in air) is essential for combustion.

· During the process of combustion, heat and light are given out.

· Ignition temperature is the lowest temperature at which a combustible substance catches


· Flame: It is a zone or burning vapour. The substances which vapourise during burning give

flames. Example: Kerosene oil and molten wax.

· Inflammable substances have very low ignition temperature.

· Fire can be controlled by removing one or more requirements essential for producing fire.

· Water is commonly used to control fires.

· Water cannot be used to control fires involving electrical equipments or oils.

· There are various types of combustions such as rapid combustion, spontaneous combustion,

explosion, etc.

· There are three different zones of a flame - dark zone, luminous zone and non-luminous