Combustible and Non-Combustible Substances
All substances around us do not burn. Based on this, substances are divided into two types
(i) Combustible Substances The substances which burn in the presence of air or oxygen are called combustible substances, e.g. petrol, LPG, kerosene, etc.
(ii) Non-combustible Substances The substances which do not burn in the presence of air or oxygen are called non-combustible substances, e.g. water, glass, sand, etc.