Fill in the blanks using the words given in the box.

ignition, petrol, combustion, calorific value, combustible, inflammable


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


(b) Wood, paper, CNG are __________ substances.


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


(d) Ignition temperature of __________ is lower than that of wood.


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


(f) The amount of heat energy produced on complete combustion of 1kg of a fuel is called its __________.

(a) Combustion


It is a process where a substance reacts with oxygen and gives off heat.


(b) Combustible


A substance that can catch fire easily is called combustible substances. Examples include wood, paper etc.


(c) Ignition


The lowest temperature at which a substance catches fire is called its ignition temperature.


(d) Petrol


Petrol is an inflammable substance


(e) Ignition, Inflammable


(f) calorific value


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