60 minute physics
Nine hands-on activities:
with GCSE Physics curriculum links
Changing
states
Mapping data
Digital
Electric
circuits
Machines &
electromagnets
Flight &
movement
Light
Storing energy
Forces &
motion
Changing
states
Changing states
STEM engagement materials developed for the Royal Air Force
Changing states
This activity forms part of a suite of physics-related activities developed by West Yorkshire STEM in
collaboration with the University of Leeds. They have been funded by the Royal Air Force to encourage
pupils to think positively about STEM generally and physics in particular. Each activity has been designed
to be interactive and linked to GCSE physics specifications of OCR and AQA. Stretch or extension activities
are provided in the content for additional follow-up beyond the session.
Changing
states
To run this activity you will need:
•A flat teaching space with enough room for small groups (of around 4 pupils) to work together
to work through activities.
•Powerpoint facilities to introduce the content and activities (using ‘Changing_states.pptx’).
(for quiz)
•Copies of ‘Changing_states_quiz.pdf’ handout for each group/pupil.
(for ‘making slime’ activity)
•1 plastic cup per student
•1 plastic food-type bag per student
•1 lollipop stick per student
•50 ml PVA glue per student
•8 tsp Borax per class
•1 L Water per class
•Paper towel
•Wet wipes
•Assorted glitter
•Assorted food colouring
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Changing
states
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‘Changing sta physics session
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•1 ‘Certificate of completion’ for each student - produced as part of these materials
(Certificate_changing_states.pdf).
Level: KS3/KS4
GCSE science curriculum links: changing state – solids, liquids, gases
Objectives of the session
•Understand the differences between solids, liquids and gases.
•Understand the difference between Newtonian and Non-Newtonian fluids.
•Understand what a ‘monomer’ and ‘polymer’ are.
Session length: 60 mins
Session overview
•The three states of matter (5 mins)
•Solid, liquid, gas quiz (10 mins)
•Unusual properties of fluids: Newtonian and Non-Newtonian (5 mins)
•Implications for everyday life (5 mins)
•Making slime (35 mins)
Extension: Changing states extension reading
Provide participants with the
background reading - produced as part
of these materials (Changing_states_extension_reading.pdf).
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Slide 1
Introduction to the session
•Introduce yourself as the facilitator and outline (briefly) your
STEM background.
•Ask STEM Ambassadors (if present) to (briefly) introduce
themselves and to say which STEM discipline/industry they
are from.
Slide 2
Three states of matter ...
•Solids: The strong bonds between molecules make solids
rigid and very difficult to deform.
•Liquids: The relatively weak bonds between molecules
allow liquids to be deformed without effort. Liquids have a
fixed volume, but their shape is determined by the shape of
the container holding them.
•Gases: Virtually no bonds exist between gas molecule so
that gases can spread into any available space. The volume
of a gas is determined by the size of the container holding
it.
•In their groups ask each to think for a couple of minutes
about examples in each – feedback and note down
responses under each.
Slide 3
Let’s test our knowledge!
•Handout: ‘Changing_states_quiz.pdf’ and ask students to
complete their own sheets and then agree a group response
once they’ve discussed with each other.
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Slide 4
1. Which of the following is NOT a gas?
•Answer: the sea is a liquid, the others are mixtures of gases.
Slide 5
2. You blow up a balloon. Is it heavier or lighter than the
un-inflated balloon?
•Answer: It’s heavier than the un-inflated balloon because
it contains more air.
Slide 6
3. Which material is a solid?
•Answer: Cotton wool is a solid! It stays in one place and is
easy to hold.
4
Slide 7
4. When you squeeze a sponge under water, what are the
bubbles that escape?
•Answer: The bubbles are air coming from the spaces in the
sponge.
Slide 8
5. Which material is a liquid?
•Answer: Shampoo is a liquid! It can be poured and takes
the shape of the container it is in.
Slide 9
6. To change a solid metal to a liquid, you would:
•Answer: Heating a metal would turn it into a liquid. Most
metals need a lot of heat before they turn into liquids.
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Slide 10
7. Which one of these best describes a liquid?
•Answer: My particles are loosely packed. I take the shape
of my container.
Slide 11
8. Which one of these best describes a gas?
•Answer: My particles have lots of room. I try to spread
out in every direction.
Slide 12
9. Which of these is NOT an example of a solid?
•Answer: Runny honey is not a solid, it’s a liquid.
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Slide 13
10. Which one of these best describes a solid?
•Answer: My particles are packed tightly together. I keep
my shape.
Slide 14
When is a fluid not really a fluid?
•Many people have heard of Sir Isaac Newton. He is famous
for developing many scientific theories in mathematics and
physics.
•Newton described how ‘normal’ liquids or fluids behave, and
he observed that they have a constant viscosity (flow). This
means that their flow behaviour or viscosity only changes
with changes in temperature or pressure. For example, water
freezes and turns into a solid at 0˚C and turns into a gas at
100˚C. Within this temperature range, water behaves like a
‘normal’ liquid with constant viscosity.
•Typically, liquids take on the shape of the container they are
poured into. We call these ‘normal liquids’ Newtonian fluids.
But some fluids don’t follow this rule. We call these ‘strange liquids’ non-Newtonian fluids.
•As pressure or speed is applied to non-Newtonian fluids their structure (viscosity) changes – which
can make them appear to be solid!
Slide 15
Slime: a non-Newtonian fluid?
Preparation
1.To prepare the Borax solution, mix 1 tsp of Borax powder for
every 125 ml of water.
2.Have food colouring, glitter, lollipop sticks and plastic cups
laid out for the students use.
3.Ensure that wet wipes and paper towels are easily accessible.
Procedure
1.Give each student a lollipop stick and a plastic cup.
2.Place approximately 50 ml of PVA glue into each student’s
plastic cup.
3.Distribute 2-3 drops of food colouring in each plastic cup and have students mix in the colouring. Students can mix colours, add glitter or create a marble affect in their glue by half-stirring in the food
colouring.
4.Place approximately 25 ml of borax solution into the plastic cups and have students mix their solution
well. The slime should turn into a more solid solution. Continue to add borax solution incrementally until
it reaches a good consistency.
5.Students and empty the contents of the plastic cups into their hands to further stir the slime together
6.Store the slime in a plastic bag to keep it from drying out.
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Slide 16
What are the uses for non-Newtonian fluids?
•If a house is built on certain types of clays and an
earthquake puts stress on this material through the
sudden movement, the apparently solid clay can turn into
a runny liquid.
•Body armour that behaves like a liquid so that you can
move easily but turns into a solid on impact from stress
could be useful for police or the military.
•Could we use Non-Newtonion fluid to fill holes in the road?
– some researchers in the USA thought this would be a
good idea – do you?
Slide 17
RAF examples: Liquid to gas!
•The RAF utilise some of the principles of liquid to solid
(non-newtonian fluids) to create body armour.
•Here we can see a member of the Royal Air Force wearing
Body Armour protection.
•The material is relatively flexible and supple until
it receives a dramatic impact – it then becomes a solid!
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