Chemistry experiments

Magic milk

or surface tension and surfactants

Surface tension and surfactants

Materials needed:

milk, water colouring
plate and a cup
cotton buds or pipette
washing up liquid and water

Instructions:

Pour milk in a place and add droplets of food colouring. Do not stir.
In a small cup mix washing up liquid and water. Dip your cotton buds in and touch the surface of the milk. Alternatively, drop a droplet with a pipette and observe. Repeat as many times as the reaction occurs.
Leave the milk to sit after you are finished. The milk will settle down in beautiful patterns (as seen in the picture on the left).

Science behind: Surfactants

In liquids you have hydrophilic and hydrophobic compounds. At the surface, the water molecules are exposed to air on one side, the water molecules experience pull downward, toward the other water molecules below them, than upward toward the air. This causes the water at the surface to contract, minimizing its surface area, which is known as surface tension. Soap, a surfactant, has a hydrophilic part that wants to interact with the water and a hydrophobic part that wants to interact with the fat molecules. Because of this, when the cotton swab with soap touched the milk, the soap separated the fat from the water in the milk. This interaction decreases the milk's surface tension around it, and the higher surface tension area pulled the milk (along with its food coloring) toward it.

Suggestions:

Use a pipette to drop soapy water in the milk and compare the movement of the milk to when cotton buds are used.

Inspired by 'Magic Box' by Katie Cleminson

orange candle

Orange candle

or wax as fuel

Materials needed:

orange (or any citrus fruit, e.g. grapefruit, pomelo, lime or lemon)
knife
oil (any type)
matches/lighter
essential oil, sparkling decoration (optional)

Instructions:

Cut your orange in half horizontally.
Take the meat out, leaving only the stem in the middle.
Pour your oil in (you can decorate with food colouring or additional essential oils), make sure the stem is soaked with oil and light up.
The candle smells gorgeous on its own and burns for hours.

Science behind: Wax as fuel

Oil acts as a fuel for the wick (stem). The wick absorbs the liquid wax and pulls it upward. The heat of flame vaporises the wax. The wick doesn't burn up because vaporising wax cools and protects it. Only the wax on the wick is hot enough to burn and vaporise the liquid wax.

Suggestions:

Experiment with different fruits and oils

Inspired by 'Burn: Michael Faraday's Candle' by Darcy Pattison

Magic porridge bubble

or sublimation

Dry ice is so much fun, it looks like magic. Use it to observe a magic pot grow!

Materials needed:

2 bowls
water
dry ice
cotton string
bubble solution
gloves

Instructions:

Fill your bowl with warm water (half full).
Add your bubble solution to the second bowl and dip your string in it.
Drop your dry ice on the bowl of water. Wear gloves.
Trace the string along the edges in a straight line and watch the bubble grow.

The science behind: Sublimation

Carbon dioxide: the molecule that animals breathe out when we exhale and plants take in when they do photosynthesis. Dry ice is the solid form of carbon dioxide that freezes at -78°C. It is pressurised when frozen to form bricks. It expands when it melts back into its gas form.

Suggestions:

Add a bit of bubble solution to your dry ice and compare

Inspired by 'The Magic Porridge Pot' by Alan Macdonald

magic porridge bubble

Bubble moon

or submination II

Have you tried making a bubble moon? Be careful not to pop it!

Materials needed:

Plastic bottle
2 funnels
tube
water
dry ice
bowl
bubble solution
tape
towel

Instructions:

Cut the top of the bottle and fit the wide side of the funnel on top of it.
Attach the tube to the narrow side of the funnel and secure it with tape.
Attach the narrow end of the second funnel to the other end of the tube and secure it with the tape.
Prepare a bowl with bubble solution, enough to dip the wide side of the funnel.
Put water and dry ice in the bottle, make sure the funnel covers the top of the bottle well. If there is any leakage secure with tape.
Dip your funnel end of the tube in water solution and observe the bubble grow. Once big enough it will drop off, if you put it on top of the towel it won't pop!

The science behind: Sublimation

Carbon dioxide: the molecule that animals breathe out when we exhale and plants take in when they do photosynthesis. Dry ice is the solid form of carbon dioxide that freezes at -78°C. It is pressurised when frozen to form bricks. It expands when it melts back into its gas form.

Suggestions:

Dip your hands with bubble solution and you'll be able to hold the bubbles in your hands!

Inspired by 'Kitten's First Full Moon' by Kevin Henkes

bubble moon

Nappy snow

or superabsorbent polymers

Do you have a spare nappy lying around? Not white Christmas this year? Or do you simply miss winter? How about some nappy snow?

Materials needed:

scissors
disposable nappy
bowl
ice-cold water

Instructions:

Cut the nappy into small pieces and take the inside of the nappy out.
Tear the inside of the nappy into tiny pieces, the smaller the better.
Once you are satisfied that you cannot make it any smaller, add some water.
Watch as the snow expands and forms right in front of your eyes.
(Alternatively, you can just take the inside out, add some water and keep squishing until you get the snow effect.）

The science behind:

Sodium polyacrylate: the secret ingredient in dipers. It is a water-absorbing chemical, a superabsorbent polymer that has the ability to absorb 100 to 1000 times its mass in water. A polymer is simply a long chain of repeating molecules that contains sodium atoms that distribute equally between the network and the water. It absorbs water by a process called osmosis

Suggestions:

If you have real snow at hand, tie their eyes and have them compare the difference based on feel only.

Inspired by 'Snow' by Uri Shulevitz

Nappy snow

Melting ice-berg

or decomposition reaction

How about an environmental twist to a popular vinegar and soda experiment?

Materials needed:

bowl and spoon
plate
paper
pipette
baking soda
water
vinegar

Instructions:

Mix baking soda and a bit of water, only enough to make the substance liquid.
Create cones out of paper and fill it with soda.
Place in the freezer and let it freeze.
Unpack the paper and place it on a plate.
Drop the vinegar on your cones and watch the icebergs melt.

The science behind:

Decomposition reaction: chemical change where sodium bicarbonate (baking soda) is reacted with acetic acid and water (vinegar) releasing carbon dioxide and making sodium acetate. This produces bubbling which is the carbon dioxide (CO2) gas being released.

Suggestions:

Make your iceberg different sizes and create a scenery suitable for polar bears
For older children touch on the question of global warming, melting icebergs and its implication for polar bears

Inspired by 'The Last Polar Bears' by Harry Horse

iceberg

colourful vulcano

Colourful volcano

or exothermic reaction

This is a different take on the typical vinegar and baking soda volcano experiment?

Materials needed:

tray, swimming pool or sensory bath
1 teaspoon of yeast
warm water
food colouring and sparklers
washing up liquid
bottle
glass and spoon
hydrogen peroxide (at least 3%, but the higher % the faster the

reaction)

Instructions:

Combine warm water (2 tablespoons) with yeast.
Pour 1/2 cup of hydrogen peroxide in the bottle, add colouring and washing up liquid.
Add the water with yeast in the bottle and enjoy.

The science behind:

Exothermic reaction: Rapid decomposition of hydrogen peroxide (breaking oxygen from hydrogen peroxide) using yeast and warm water as a catalyst. The faster the reaction the more bubbles are created. The foam produced is just water, soap, and oxygen that are warm to touch.

Suggestions:

Discuss that lava is also hot
Prepare hydrogen peroxide at 3%, 6%, and 20% and observe the change in the speed of the reaction

Inspired by 'Going to the volcano' by Andy Stanton and Miguel Ordonez

dancing grains

Dancing grains

or decomposition reaction II

How about an environmental twist to a popular vinegar and soda experiment?

Materials needed:

glass and spoon
baking soda
vinegar
water
grains/beans/rice/broken spaghetti/small light object

Instructions:

Mix baking soda and in a glass of water and mix until completely dissolved
Add your 'dancing grains'.
Start adding a bit of vinegar at a time, do not add too much at once or the glass might overflow.
After a few spoonfuls, you should start seeing your grains going up and down the glass.

The science behind:

Decomposition reaction: chemical change where sodium bicarbonate (baking soda) is reacted with acetic acid and water (vinegar) releasing carbon dioxide and making sodium acetate. This produces bubbling which is the carbon dioxide (CO2) gas being released. The CO2 lifts the grains up to the surface of the water as it is being released. Once it is released, the grains fall back down.

Suggestions:

Use different grains and compare the speed of their 'dance'

I

M

...because the simplest of words become stories for a lifetime...

Magic milk

or surface tension and surfactants

Surface tension and surfactants

Materials needed:

milk, water colouring

plate and a cup

cotton buds or pipette

washing up liquid and water

​

Instructions:

Pour milk in a place and add droplets of food colouring. Do not stir.

In a small cup mix washing up liquid and water. Dip your cotton buds in and touch the surface of the milk. Alternatively, drop a droplet with a pipette and observe. Repeat as many times as the reaction occurs.

Leave the milk to sit after you are finished. The milk will settle down in beautiful patterns (as seen in the picture on the left).

Science behind: Surfactants

Suggestions:

Use a pipette to drop soapy water in the milk and compare the movement of the milk to when cotton buds are used.

Orange candle

or wax as fuel

​

Materials needed:

orange (or any citrus fruit, e.g. grapefruit, pomelo, lime or lemon)

knife

oil (any type)

matches/lighter

essential oil, sparkling decoration (optional)

​

Instructions:

Cut your orange in half horizontally.

Take the meat out, leaving only the stem in the middle.

Pour your oil in (you can decorate with food colouring or additional essential oils), make sure the stem is soaked with oil and light up.

The candle smells gorgeous on its own and burns for hours.

Science behind: Wax as fuel

Oil acts as a fuel for the wick (stem). The wick absorbs the liquid wax and pulls it upward. The heat of flame vaporises the wax. The wick doesn't burn up because vaporising wax cools and protects it. Only the wax on the wick is hot enough to burn and vaporise the liquid wax.

Suggestions:

Experiment with different fruits and oils

Magic porridge bubble

or sublimation

Dry ice is so much fun, it looks like magic. Use it to observe a magic pot grow!

Materials needed:

2 bowls

water

dry ice

cotton string

bubble solution

gloves

​

Instructions:

Fill your bowl with warm water (half full).

Add your bubble solution to the second bowl and dip your string in it.

Drop your dry ice on the bowl of water. Wear gloves.

Trace the string along the edges in a straight line and watch the bubble grow.

The science behind: Sublimation

Carbon dioxide: the molecule that animals breathe out when we exhale and plants take in when they do photosynthesis. Dry ice is the solid form of carbon dioxide that freezes at -78°C. It is pressurised when frozen to form bricks. It expands when it melts back into its gas form.

Suggestions:

Add a bit of bubble solution to your dry ice and compare

Bubble moon

or submination II

Have you tried making a bubble moon? Be careful not to pop it!

​

Materials needed:

Plastic bottle

2 funnels

tube

water

dry ice

bowl

bubble solution

tape

towel

​

Instructions:

Cut the top of the bottle and fit the wide side of the funnel on top of it.

Attach the tube to the narrow side of the funnel and secure it with tape.

Attach the narrow end of the second funnel to the other end of the tube and secure it with the tape.

Prepare a bowl with bubble solution, enough to dip the wide side of the funnel.

Put water and dry ice in the bottle, make sure the funnel covers the top of the bottle well. If there is any leakage secure with tape.

Dip your funnel end of the tube in water solution and observe the bubble grow. Once big enough it will drop off, if you put it on top of the towel it won't pop!

Materials needed: