MATTER IN OUR SURROUNDINGS
SUCCESS CRITERIA
SUCCESS CRITERIA
ACTIVITY
1.1
(10 marks)
Date
Diagram
Observation
Explanation
Conclusion
I have mentioned the
date on which the
experiment was
performed.
 I have drawn
a diagram.
 My diagram is neat.
 My diagram is well –
labeled.
I have mentioned the
following keywords:
I have mentioned the
following keywords:
I have mentioned the following
keywords:
On addition of salt/ sugar the
water level does not change.
 Particles of water have
spaces between them.
 Particles of salt occupy the
spaces between the
particles of water.
 Matter is made up of particles.
 Particles of water have big
spaces between them.
 Particles of salt are small
enough to fit into the spaces
between the particles of water.
1 mark
3 marks
1 mark
2 marks
3 marks
SUCCESS CRITERIA
Date
Diagram
Observation
Explanation
Conclusion
I have mentioned
the date on which
the experiment
was performed.
 I have drawn
a diagram.
 My diagram is neat.
 My diagram is well –
labeled.
I have mentioned the
following keywords:
I have mentioned the
following keywords:
I have mentioned the following
keywords:
With every dilution the colour
of potassium permanganate
in water becomes lighter.
 A few crystals of potassium
permanganate can colour a
large quantity of water.
 Matter is made up of extremely
small particles.
ACTIVITY 1.2
(8 marks)
 There must be millions of
tiny particles of potassium
permanganate in just one
crystal of potassium
permanganate.
1 mark
3 marks
1 mark
2 marks
1 mark
SUCCESS CRITERIA
Date
Diagram
Observation
I have mentioned
the date on which
the experiment
was performed.
I have mentioned the
 I have drawn
following keywords:
a diagram.
 My diagram is neat.
 My diagram is well –  I could not smell the unlit
incense stick from a
labeled.
distance.
 I could smell the lighted
incense stick from a
distance.
ACTIVITY 1.3
(16 marks)
1 mark
3 marks
2 marks
Explanation
Conclusion
I have mentioned the
following keywords:
I have mentioned the following
keywords:
 A burning incense stick
releases fragrant smoke.
 This smoke consists of
particles which have high
kinetic energy.
 The smoke particles with
high kinetic energy travel
through the big spaces
between the air particles.
 This intermixing of particles
of smoke and air is
diffusion.
 Unlit incense sticks do not
have high energy fragrant
smoke particles. Hence we
are not able to smell them.
 Particles of matter move.
 Therefore, particles of matter
possess kinetic energy.
 Increase in temperature of
matter causes its particles to
move faster.
 The kinetic energy of particles
increases with increase in
temperature.
 The rate of diffusion becomes
higher with rise in temperature.
5 marks
5 marks
SUCCESS CRITERIA
ACTIVITY
1.4
(8 marks)
Date
Diagram
I have mentioned the
date on which the
experiment was
performed.
I have mentioned the
 I have drawn
following keywords:
a diagram.
 My diagram is neat.
 My diagram is well –  The ink diffuses at a faster
rate than honey.
labeled.
1 mark
3 marks
Date
I have mentioned
the date on
which the
experiment was
performed.
Diagram
 I have drawn
a diagram.
 My diagram is
neat.
 My diagram is
well – labeled.
1 mark
3 marks
ACTIVITY
1.5
(13 marks)
Observation
1 mark
Explanation
Conclusion
I have mentioned the following
keywords:
I have mentioned the
following keywords:
 ink has very small solid particles
dissolved in water.
 honey has large particles held
together by strong intermolecular forces of attraction.
2 marks
 Larger particles diffuse
slowly while small particles
diffuse faster.
1 mark
SUCCESS CRITERIA
Observation
Explanation
Conclusion
I have mentioned the
I have mentioned the following keywords:
I have mentioned the
following keywords:
following keywords:
 Water molecules are continuously in
 In water potassium
permanganate crystals
motion. The water molecules collide
 Particles of matter are in
first settle down and then
against the potassium permanganate
continuous motion.
slowly diffuse in the
crystals and break them down into
 Increase in temperature
water. A dense purple
smaller particles.
increases the kinetic
solution
 The smaller potassium permanganate
energy of the particles.
particles are able to move faster.
 Rate of diffusion becomes
 Potassium permanganate  Due to the random continuous motion of
higher on heating.
diffuses faster in hot
water molecules and potassium
water than in cold water.
permanganate particles diffusion finally
takes place.
 In hot water the molecules of water move
faster and have higher kinetic energy
than in cold water. The high energy water
molecules collide with the potassium
permanganate particles with more
energy. Hence diffusion is faster.
2 marks
4 marks
3 marks
SUCCESS CRITERIA
ACTIVITY
1.7
(5 marks)
Date
Observation
Explanation
Conclusion
I have mentioned the
date on which the
experiment was
performed.
I have mentioned the
following keywords:
I have mentioned the following
keywords:
I have mentioned the following
keywords:
 It is easiest to break the
chalk and most difficult to
break the iron nail.
 The particles in the iron nail
have the strongest forces of
attraction between them.
 Particles of matter have forces of
attraction between them which
hold them together.
 The strength of this force of
attraction between particles differs
from one matter to another.
NO DIAGRAM
REQUIRED
1 mark
1 mark
1 mark
2 marks
SUCCESS CRITERIA
ACTIVITY
1.8
(7 marks)
Date
Observation
Explanation
Conclusion
I have mentioned the
date on which the
experiment was
performed.
I have mentioned the
following keywords:
I have mentioned the
following keywords:
I have mentioned the following
keywords:
1 mark
NO DIAGRAM
REQUIRED
 It is easy to break the
stream of water with one’s
fingers.
 The stream of water rejoins
once we remove our
fingers.
2 marks
 The particles of water are
loosely packed hence ir is
easy to break the stream
of water.
 The water stream rejoins
due to the forces of
attraction between the
particles of water.
2 marks
 Particles of matter attract each
other.
 Particles of water have large
spaces between them.
2 marks
SUCCESS CRITERIA
ACTIVITY
1.11
(7 marks)
Date
Diagram
Observation
I have mentioned the
date on which the
experiment was
performed.
I have mentioned the
 I have drawn
following keywords:
a diagram.
 My diagram is neat.
 My diagram is well –  It was easiest to push the
piston in the syringe which
labeled.
had only air.
1 mark
3 marks
1 mark
Explanation
Conclusion
I have mentioned the
following keywords:
I have mentioned the following
keywords:
 There are large spaces
between the particles of
air.
1 mark
 Solids and liquids cannot be
compressed and they occupy
definite volumes.
 Gases can be easily compressed
due to the large spaces between
their particles.
 Gases do not have a definite
volume.
3 marks
MCQs – Particle Model of solids, Liquids and Gases
1.
2.
Which of the following best describes a SOLID?

fills container, takes shape of container, flows easily, low density

definite volume, definite shape, does not readily flow, high density

definite volume, takes shape of container, flows easily, high density

fills container, definite shape, does not readily flow, low density
The table shows the melting points and boiling points of some substances A to D. Which substance is a liquid at
-10 C and a gas at 10oC?
Melting Point oC and Boiling Point oC
o
3.
4.
5.

-66 and 42

-142 and -78

-95 and 4

90 and 189
BOILING is the state change from?

liquid to gas

gas to liquid

liquid to solid

solid to liquid
Air is in a bottle with a tight screw-top. When the bottle becomes cooler, the pressure inside decreases
because the molecules of air?

move faster

move slower

become bigger

become smaller
The table below shows the melting points and boiling points of substances A to D. Which substance is suitable
to use in a thermometer that measures in the range -4oC to 50oC?
Melting point oC (mpt), Boiling Point oC (bpt)

mpt = 0, bpt = 100

mpt = -110, bpt = 80

mpt = 40, bpt = 350

mpt = -200, bpt = 40
6.
7.
8.
9.
10.
11.
The diagram shows an experiment using a light colourless gas (air) and a heavier brown coloured gas (bromine
or nitrogen dioxide). The gases fully mix together because?

all the gas particles can move around freely

of convection currents in the air

the gases have different densities (one is 'lighter' or 'heavier' than the other)

the air can sink into the coloured gas and the coloured gas can float on air
The diagram shows an experiment using a light colourless gas (air) and a heavier brown coloured gas (bromine
or nitrogen dioxide). The gases spread around in the gas jars by a process called?

evaporation

condensation

diffusion

sedimentation
Which of the following is the opposite of evaporating?

condensing

melting

freezing

boiling
Which of the following best EXPLAINS why liquids flow much more easily than solids?

liquid particles are lighter than solid particles

liquid particle attractive forces are weaker than solid particle attractive forces

liquid particles have more energy than solid particles

liquid particles can change shape more easily than solid particles
CONDENSING is the state change from?

liquid to solid

gas to liquid

liquid to gas

solid to liquid
Which describes sand?

a liquid

a gas

difficult to classify simply as gas, liquid or solid

12.
13.
14.
15.
16.
a solid
Starting with the solid, the graph shows the results of
measuring the temperature of substance X as it was heated from a low to a high temperature. Which of the
following is TRUE?

X is melting between times t0 and t1

X is boiling between times t2 and t3

temperature TE1 is the melting point of X

X is completely liquid between times t1 and t2
Which of the following best describes what happens to the particles of water vapour when it condenses?

They lose energy and and are closer and less free to move around

They gain energy and increase their freedom to move without significant attractio

They lose energy and lose freedom to move about

They gain energy and gain freedom to move about
Which of the following best EXPLAINS why the liquid in a glass thermometer expands with rise in
temperature?

the liquid particles get bigger expanding the liquid

the glass contracts forcing the liquid further up the tube

the liquid particles gain more energy and collide more forcefully

the glass particles gain more energy and push the liquid particles up the tube
Which of these is a gas?

sand

water

rock

oxygen
Gases diffuse because they?

have a low density

easily move as convection currents
17.
are made of rapidly moving particles

have low boiling points
Which describes carbon dioxide?
18.
19.


a gas

a liquid

difficult to classify simply as gas, liquid or solid

a solid
Water turning to a solid is called?

freezing

boiling

condensing

melting
The table shows the melting points and boiling points of some substances A to D. Which substance is a liquid at
20 C?
Melting Point oC and Boiling Point oC
o
20.

-142 and -78

-95 and 4

-66 and 42

90 and 189
Which of the following best describes what happens to the particles of ice when it melts?

They lose energy and lose freedom to move about

They lose energy and escape into the atmosphere

They gain energy and gain freedom to move about

They gain energy and break up into atoms of hydrogen and oxy
THE THREE STATES OF MATTER
GAS-LIQUID-SOLID PARTICLE THEORY MODELS
1. Particle model of gases





A gas has no fixed shape or volume, but always spreads out to fill any container.
There are almost no forces of attraction between the particles so they are completely free of each
other.
The particles are widely spaced and scattered at random throughout the container so there is no order
in the system.
The particles move rapidly in all directions, frequently colliding with each other and the side of the
container.
With increase in temperature, the particles move faster as they gain kinetic energy.
Using the particle model to explain the properties of a Gas

Gases have a very low density (‘light’) because the particles are so spaced out in the container (density
= mass / volume).
o

Density order: solid > liquid >>> gases
Gases flow freely because there are no effective forces of attraction between the gaseous particles molecules.

o
Ease of flow order: gases > liquids >>> solids (no real flow in solid unless you powder it!)
o
Because of this gases and liquids are described as fluids.
Gases have no surface, and no fixed shape or volume, and because of lack of particle attraction, they
always spread out and fill any container (so gas volume = container volume).

Gases are readily compressed because of the ‘empty’ space between the particles.
o

Ease of compression order: gases >>> liquids > solids (almost impossible to compress a solid)
Gas pressure
o
When a gas is confined in a container the particles will cause and exert a gas pressure which is
measured in atmospheres (atm) or Pascals (Pa = N/m2) - pressure is force/area on which force is
exerted.

The gas pressure is caused by the force created by millions of impacts of the tiny individual
gas particles on the sides of a container.

For example - if the number of gaseous particles in a container is doubled, the gas pressure
is doubled because doubling the number of molecules doubles the number of impacts on the
side of the container so the total impact force per unit area is also doubled.
This doubling of the particle impacts doubling the pressure is pictured in the two diagrams below.
2x
particles
===>
Px2

If the volume of a sealed container is kept constant and the gas inside is heated to a higher
temperature, the gas pressure increases.
o
The reason for this is that as the particles are heated they gain kinetic energy and on average
move faster.
o
Therefore they will collide with the sides of the container with a greater force of impact, so
increasing the pressure.
DIFFUSION in Gases:

The natural rapid and random movement of the particles in all directions means that gases readily
‘spread’ or diffuse.

Diffusion is faster in gases than liquids where there is more space for them to move (experiment
illustrated below) and diffusion is negligible in solids due to the close packing of the particles.

Diffusion is responsible for the spread of odours even without any air disturbance e.g. use of
perfume, opening a jar of coffee or the smell of petrol around a garage.

The rate of diffusion increases with increase in temperature as the particles gain kinetic energy
and move faster.

Other evidence for random particle movement including diffusion:
When smoke particles are viewed under a microscope they appear to 'dance around' when illuminated
with a light beam at 90o to the viewing direction. This is because the smoke particles show up by
reflected light and 'dance' due to the millions of random hits from the fast moving air molecules. This is
called 'Brownian motion' (see below in liquids). At any given instant of time, the hits will not be even,
so the smoke particle get a greater bashing in a random direction.
2. Particle model of Liquids

A liquid has a fixed volume at a given temperature but its shape is that of the container which holds
the liquid.

There are much greater forces of attraction between the particles in a liquid compared to gases, but not
quite as much as in solids.

Particles quite close together but still arranged at random throughout the container, there is a little close
range order as you can get clumps of particles clinging together temporarily.

Particles moving rapidly in all directions but more frequently collisions with each other than in gases
due to shorter distances between particles.

With increase in temperature, the particles move faster as they gain kinetic energy, so increased
collision rates, increased collision energy and increased rate of diffusion.
Using the particle model to explain the properties of a Liquid

Liquids have a much greater density than gases (‘heavier’) because the particles are much closer
together because of the attractive forces.

Most liquids are just a little less dense than when they are solid
o

Water is a curious exception to this general rule, which is why ice floats on water.
Liquids usually flow freely despite the forces of attraction between the particles but liquids are not as
‘fluid’ as gases.
o
Note 'sticky' or viscous liquids have much stronger attractive forces between the molecules
BUT not strong enough to form a solid.

Liquids have a surface, and a fixed volume (at a particular temperature) because of the increased particle
attraction, but the shape is not fixed and is merely that of the container itself.
o
Liquids seem to have a very weak 'skin' surface effect which is caused by the bulk molecules
attracting the surface molecules disproportionately.

Liquids are not readily compressed because there is so little ‘empty’ space between the particles, so
increase in pressure has only a tiny effect on the volume of a solid, and you need a huge increase in pressure
to see any real contraction in the volume of a liquid.

Liquids will expand on heating but nothing like as much as gases because of the greater particle attraction
restricting the expansion (will contract on cooling).
o
Note: When heated, the liquid particles gain kinetic energy and hit the sides of the container more
frequently, and more significantly, they hit with a greater force, so in a sealed container the pressure
produced can be considerable!

The natural rapid and random movement of the particles means that liquids ‘spread’ or diffuse.
Diffusion is much slower in liquids compared to gases because there is less space for the particles to move
in and more ‘blocking’ collisions happen.
o
Just dropping lumps/granules/powder of a soluble solid (preferably coloured!) will resulting in a
dissolving followed by an observable diffusion effect.
o
Again, the net flow of dissolved particles will be from a higher concentration to a lower
concentration until the concentration is uniform throughout the container.

Diffusion in liquids - evidence for random particle movement in liquids:
o
If coloured crystals of e.g. the highly coloured salt crystals of potassium permanganate are dropped
into a beaker of water and covered at room temperature.
o
Despite the lack of mixing due to shaking or convection currents from a heat source etc. the bright
purple colour of the dissolving salt slowly spreads throughout all of the liquid but it is much slower than
the gas experiment described above because of the much greater density of particles slowing the
spreading due to close proximity collisions.
o
The same thing happens with dropping copper sulphate crystals (blue, so observable) or coffee granules
into water and just leaving the mixture to stand.
Particle model of Solids

A solid has a fixed volume and shape at a particular temperature unless physically subjected to
some force.

The greatest forces of attraction are between the particles in a solid and they pack together as tightly
as possible in a neat and ordered arrangement.

The particles are too strongly held together to allow movement from place to place but the particles
vibrate about their position in the structure.

With increase in temperature, the particles vibrate faster and more strongly as they gain kinetic
energy.
Using the particle model to explain the properties of a Solid

Solids have the greatest density (‘heaviest’) because the particles are closest together.

Solids cannot flow freely like gases or liquids because the particles are strongly held in fixed positions.

Solids have a fixed surface and volume (at a particular temperature) because of the strong particle
attraction.

Solids are extremely difficult to compress because there is no real ‘empty’ space between the particles,
so increase in pressure has virtually no effect on the volume of a solid.

Solids will expand a little on heating but nothing like as much as liquids because of the greater particle
attraction restricting the expansion and contraction occurs on cooling.
o
The expansion is caused by the increased energy of particle vibration, forcing them further apart
causing an increase in volume and corresponding decrease in density.

Diffusion is almost impossible in solids because the particles are too closely packed and strongly held
together with no ‘empty space’ for particles to move through.