1. Can Matter Change its State?
• Can matter really change its state?
• What happens to the particles of matter
during the change of its state?
• How does this change of state take place?
PRESENTATION BY: NARESH SINGH RANA
2. Everything in this universe is made up of material which scientists have named
“matter”. The air we breathe, the food we eat, stones, clouds, stars, plants and
animals, even a small drop of water or a particle of sand- each thing is matter.
•MATTER IS MADE UP OF PARTICLES
•THESE PARTICLES ARE VERY SMALL- They are
small even beyond our imagination!!!
•THEY HAVE SPACE BETWEEN THEM
•THEY MOVES CONTINUOUSLY
•THEY ATTRACT EACH OTHER
3. Matter around us exists in three different states- solid, liquid and gas. These states of
matter arise due to the variation in the characteristics of the particles of matter.
SOLID LIQUID GAS
4. Yes, matter can change its state and to show that, the matter can change its state,
water is probably the best example to easily explain and understand too. As we all
know that water can exists in three state of matter-
Solid, as ice
Liquid, as
water
Gas, as
water vapour
5. Conversion of ice to water, then conversion of water to water vapour
•Take a beaker and put some ice into it,
•Start heating the beaker on a low flame,
•Observe it until all the ice has converted into water.
•This is the conversion of solid to liquid state.
•Now heat the beaker till the water starts boiling,
•Keep a careful eye on it till the most of the water has
vaporised,
•Observe the conversion of water in the liquid state to the
gaseous state.
*See the diagram in the next slide…
6. Fig.: (a) Conversion of ice to water, (b) conversion of water to water vapour
Beaker Beaker
Burner Burner
Ice Water
Water vapour
(a) (b)
7. •The energy supplied by heat overcomes the forces of attraction between the particles
of solids. The particles leave their fixed positions and start moving freely. A stage is
reached when the solid melts and converted to a liquid.
•The temperature at which a solid melts to become a liquid
at the atmospheric pressure is called its melting point.
•When we supply heat energy to water, particles starts moving even faster. At a certain
temperature, a point is reached when the particles have enough energy to break free
from the forces of attraction of each other. At this temperature liquid starts changing
into gas.
•The temperature at which a liquid starts boiling at the
atmospheric pressure is known as its boiling point.
Solid State Liquid State Gaseous State
Heat Heat
Cool Cool
8. So, we infer that the state of matter can be changed into another state by changing the
temperature. Substances around us change state from solid to liquid and from liquid to
gas on application of heat. But there are some that change directly from solid state to
gaseous state and vice verse without changing into the liquid state.
•A change of state directly from solid to gas without
changing into liquid state (or vice versa) is called
sublimation.
Liquid
Solid Gas
Sublimation
Sublimation
Fig.: Interconversion of the three states of matter
9. Yes, matter can change its state.
Thus, we can say that pressure and temperature determine the state of a substance,
whether it will be solid, liquid or gas.
