chapter 1 for class 9 from maharashtra board

1. World of Matter

2. What is matter
Matter is something that occupies space and has mass.
Matter Non – Matter

3. Matter is made up of small particles
Every substance is made up on small particles (called molecules). Each particle has
the same properties as the original substance.
A chemical bond holds the particles together. The strength of the bond between the
particles determines many properties of that substance.

4. Particles of matter are in motion
If you add a few drops of potassium permanganate to
water you will observe that the color of the entire
solution will change even if you don’t stir the solution.
This is because particles of matter are always in
motion.
Particles of a solid vibrate in their place while those of
liquid and gas can move about more freely.

5. There is gap between particles
There is a lot of gap in between two
particles of a substance.
When you add potassium permanganate to
water, the particles of potassium
permanganate occupy the space between
the water particles.
Water molecule
Potassium permanganate molecule
Solid Liquid Gas
There is very little empty space between
particles in a solid.
Gases have the maximum amount of empty
space between particles

6. Properties of Matter
Matter is made up on small particles.
Particles of matter are held together by a chemical bond.
Every particle of matter has the same properties.
Particles of matter are in constant motion.
There is gap between the particles of matter.

7. States of matter
Plasma – Highly excited gas which has lost its electrons
Solid
Liquid
Gas
Plasma

8. States of matter
Solid
Has a fixed shape
Has fixed volume
Very hard to compress
Little empty space between particles
Particles vibrate in their place
Strong chemical bonds hold the
particles together
Liquid
No fixed shape
Takes the shape of the container
Has fixed volume
Can be compressed a bit
Little empty space between particles
Particles can move about freely
within the liquid
Chemical bonds in liquids are
weaker than in solids
Gas
No fixed shape
No fixed volume
Takes the volume of the container
Easily compressible
Large empty space between
particles
Particles have high energy and more
about randomly
Gases have the weakest chemical
bonds amongst the three

9. Viscosity
viscosity describes a liquid’s resistance to
flow.
Honey is more viscous then kerosene which is more viscous
then water.
Honey Kerosene Water

10. 120
90
60
30
0
2 4 6 8 100
Temperature(°C)
Time (s)
-30
Changing the state of matter
Boiling Point
Melting Point

11. What happens on heating
 Matter is made up on small particles which are in constant motion.
 When you heat matter, the particles of matter absorb the heat energy and begin
moving faster (in other words they gain kinetic energy).
 As more energy is provided the chemical bond between the particles become weaker
and hence there is change is the state of matter.
 Latent heat is the heat absorbed or released when matter undergoes a change of
state without a change in it temperature.
 Latent heat of fusion – Melting
 Latent heat of vaporization – Boiling

12. Changing the state of matter
SOLIDS
LIQUID
S
GASES
PLASMAS
EACH ADDITION OF
ENERGY CREATES
A CHANGE IN
STATE

13. Conversion from on state to another
LIQUID
condensation
evaporation
sublimation
deposition
melting
freezing
De-ionization
Ionization
PLASMA
GAS
SOLID

14. Evaporation
Evaporation is a type of vaporization of a liquid that occurs
only on the surface of a liquid.
Rate of evaporation depends up on surface area, temperature, flow of air and
concentration of the substance in air (humidity)
When the molecules collide, they transfer energy to each other. Sometimes during
the transfer a molecule near the surface ends up with enough energy to escape.
Evaporation is all about the energy in individual molecules.

15. Sublimation
Some substances like ammonium chloride, camphor,
dry ice (solid CO2) and naphthalene on heating
transition directly from solid state to gaseous state.
This direct transition from solid state
to gaseous state is known as
sublimation.
Take some ammonium chloride in a china dish. Place
an inverted glass funnel over it. Heat the dish gently.
Ammonium chloride converts directly from solid state
to gaseous state.
Ammonium
chloride
vapours
Cotton plug
Inverted
funnel
Ammonium
chloride
solidified
China dish
Burnner

16. CONDENSE
INTO LIQUIDS
MATTER
SOLID LIQUIDS GASES
MELT INTO LIQUIDS
SUBLIMATE INTO GASES
EVAPORATE INTO GASES
FREEZE INTO SOLIDS
CAN BE
CONVERTED
INTO
CAN BE
CONVERTED
INTO