Fill in the blanks in the following sentences.

(a) A ____________ process in which a substance reacts with __________ to give off heat is called combustion.


(b) When the clothes of a person catch __________, the person is covered with a __________ to extinguish fire.


(c) The __________ temperature at which a substance catches fire is called its __________ temperature.


(d) The substances which have very ________________ ignition temperature and can easily catch fire with a flame are called __________ substances.


(e) The substances which vapourise during __________, give flame.


(a) Chemical and Oxygen

Combustion takes place only in the presence of Oxygen.


(b) Fire and Blanket.


A blanket helps prevent oxygen from entering into the cloth which is on fire, and thus helps prevent fire.


(c) Lowest and Ignition.


The minimum temperature at which a substance catches fire is known as the Ignition Temperature.


(d) Low and Inflammable.


Low ignition temperature implies that the substance can catch fire as soon as it is exposed to it. This temperature is known as Ignition Temperature.


(e) Burning


On heating a substance, it produces fire. A flame is produced when a substance is burnt.


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