What is Meant by Ignition Temperature and Inflammable Substances? Video Lecture | Science Class 8

ignition temperature ignition
temperature of a substance is the
minimum temperature required for the
substance to catch fire the substances
which have a very low ignition
temperature and catch fire at a very low
temperature are called in flammable
substances Patrol and LPG are the
examples of inflammable substances the
following activity shows that for a
substance to catch fire
it must be heated to its ignition
temperature prepare two paper cups in
the shape of a cone and fill one of the
cups with water heat these two cups
separately on the steady flame of a
candle the empty paper cup catches fire
very quickly but the paper cup filled
with water does not catch fire easily
this can be explained as follows the
empty paper cup has nothing but air
inside it and burns as soon as it's
ignition temperature is reached the
paper cup with water does not catch fire
because the heat supplied to it is
conducted to the water inside it
hence the presence of water increases
the ignition temperature of the paper
and therefore the cup doesn't burn