World of Matter
Standard 9
What is matter
Matter is something that occupies space and has mass.
Matter
Non – Matter
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.
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.
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
There is very little empty space between
particles in a solid.
Solid
Liquid
Gas
Gases have the maximum amount of
empty space between particles
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.
States of matter
Gas
Plasma
Liquid
Solid
Plasma – Highly excited gas which has lost its electrons
Bose-Einstein Condensate NEW! – matter at the coldest temperatures (0.000,000,001°K)
States of matter
Solid
Liquid
Gas
Has a fixed shape
No fixed shape
Takes the shape of the container
No fixed shape
Has fixed volume
Has fixed volume
No fixed volume
Takes the volume of the container
Very hard to compress
Can be compressed a bit
Easily compressible
Little empty space between particles
Little empty space between particles
Large empty space between
particles
Particles vibrate in their place
Particles can move about freely
within the liquid
Particles have high energy and more
about randomly
Strong chemical bonds hold the
particles together
Chemical bonds in liquids are
weaker than in solids
Gases have the weakest chemical
bonds amongst the three
Viscosity
Viscosity describes a liquid’s resistance to flow.
Honey is more viscous then kerosene which is more viscous then water.
Changing the state of matter
120
Boiling Point
Temperature (°C)
90
60
30
Melting Point
0
-30
0
2
6
4
Time (s)
8
10
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
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.
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.
Evaporation
Evaporation is a type of vaporization of a liquid that occurs
only on the surface of a liquid.
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.
Rate of evaporation depends up on surface area, temperature, flow of air and
concentration of the substance in air (humidity)
Conversion from on state to another
BEC
De-ionization
Gas
Plasma
Ionization
sublimation
condensation
evaporation
deposition
freezing
Liquid
melting
Solid