States of Matter
Aim and Objectives
• Aim:
• Give the learner an understanding of physical changes
• Learning Outcomes:
• Understand the arrangement of particles in solids,
liquids and gases
• Describe physical changes and relate them to energy
• Explain why evaporation happens and why it is a
cooling process
Solids, Liquids and Gases
Introducing states of matter
The particle model
Properties of solids, liquids and gases
Diffusion
Summary activities
Different substances
What are the names of the substances described in this table?
(The first letters spell out another word for ‘substance’.)
Liquid metal
Solid used in aircraft
Solid used to coat steel cans
Intoxicating liquid
Radioactive solid
Solid that rusts
Unreactive gas
Solid used by Roman plumbers
Aluminium
Lead
Ethanol
Radium
Tin
What different types of materials are there? Argon
Iron
Mercury
Three states of matter
At room temperature most substances exist in one of three
physical states.
solid
liquid
gas
Solid, liquid or gas?
Solid, liquid or gas?
Solids, Liquids and Gases
Introducing states of matter
The particle model
Properties of solids, liquids and gases
Diffusion
Summary activities
The Particle Model
The difference between solids, liquids and gases can be
explained by the…
 All substances are made up of particles.
 The particles are attracted to each other. Some particles
are attracted strongly to each other and others weakly.
 The particles move around. They are described as
having kinetic energy.
 The kinetic energy of the particles increases with
temperature.
Particles in a solid – animation
Particles in a liquid – animation
Particles in a gas – animation
Solids, Liquids and Gases
Introducing states of matter
The particle model
Properties of solids, liquids and gases
Diffusion
Summary activities
Properties of solids, liquids and gases
Which state of matter am I?
Solids, Liquids and Gases
Introducing states of matter
The particle model
Properties of solids, liquids and gases
Diffusion
Summary activities
How do smells spread out?
Where is the smell coming from and how does it spread out?
What is diffusion?
Diffusion is the movement of
particles that allows them to spread
out and mix with other particles.
For example, the smell of aftershave
or perfume diffuses and is detected by
people on the other side of the room.
Use the particle model to explain these facts about diffusion:
 Diffusion occurs in liquids and gases but hardly at all in
solids.
 Diffusion happens more quickly for gases than for liquids.
 Diffusion happens more quickly at warm temperatures
than at cooler temperatures.
Diffusion animation 1
Diffusion animation 2
Diffusion experiment
In this experiment, two gases diffuse towards each other in
a sealed glass tube.
cotton wool soaked
in ammonia
solution
gases cotton wool soaked
meet in concentrated
here hydrochloric acid
When the gases meet, they react to form a ring of ammonium
chloride which is closer to one end of the tube than the other.
Which gas particles diffuse faster, ammonia or acid, and why?
Solids, Liquids and Gases
Introducing states of matter
The particle model
Properties of solids, liquids and gases
Diffusion
Summary activities
Glossary
diffusion – Particles spreading out and mixing in the gas
or liquid state.
gas – The state of matter in which particles move quickly
in all directions and rarely touch each other.
liquid – The state of matter in which particles are
randomly arranged and touch each other.
matter – The stuff that everything is made of.
particle – The smallest unit of matter.
pressure – The force produced when particles move
against a surface.
solid – The state of matter in which particles are in a fixed
arrangement and touch each other.
Anagrams
Crossword
Across:
2. Change from liquid to solid
5. Force caused by collisions of
particles
6. Arranged in a 3-dimensional
pattern
9. Spacing of particles in solids
and liquids
10. All substances are this state
at very low temperatures
11. Only liquids and gases do this
1
2
3
4
5
6
7
8
9
10
11
Down:
1. Closely packed particles
6. Particles are close but disorganised
3. Change from gas to liquid 7. Particles widely spread out
4. Change from solid to liquid 8. Change from liquid to gas
Multiple-choice quiz