World of Matter

Standard 9

What is matterMatter 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 particlesThere 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

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

Plasma – Highly excited gas which has lost its electrons

Bose-Einstein Condensate NEW! – matter at the coldest temperatures (0.000,000,001°K)

SolidLiquid

GasPlasma

States of matter

Solid Liquid GasHas a fixed shape No fixed shape

Takes the shape of the containerNo fixed shape

Has fixed volume Has fixed volume No fixed volumeTakes 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.

120

90

60

30

0

2 4 6 8 100

Tem

pera

ture

(°C)

Time (s)

-30

Changing the state of matter

Boiling Point

Melting Point

What happens on heatingMatter 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 – MeltingLatent heat of vaporization – Boiling

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.

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.

Conversion from on state to another

SolidLiquid

GasPlasma

condensation

evaporation

sublimation

deposition

melting

freezing

De-ionization

Ionization

BEC