Elephant’s Toothpaste: The Chemical Genie
Elephant’s Toothpaste: The Chemical Genie
Professor Picklebottom thinks something is trapped inside this bottle.
It isn’t a genie… but it might behave like one.
Add one special ingredient and watch what happens when the Chemical Genie escapes.
What do you think is hiding inside?
5-12 yrs
Easy
20
min
Stage 3
Mission Briefing.
Designed by Darin Carr (BSc, DipEd)
NESA Accredited Teacher Chemistry & Physics Specialist
Creator of the LAB™ Learning System
Mackey
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Elephant’s Toothpaste: The Chemical Genie
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NESA Accredited Teacher
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High school chemistry & physics specialist 30+ years
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The Crazy Scientist in primary schools — 15 years
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International conference presenter on science education
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Creator of the LAB™ Learning System
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Curriculum aligned: NSW Science & Technology K–6 (2024)
A picture is worth a thousand words — check this out and see if you can spot the science hiding in plain sight.
Mission Equipment
• 1 empty plastic bottle — a 600mL
• 120mL (½ cup) hydrogen peroxide — 3%
• 1 tablespoon dry yeast
• 3 tablespoons warm water — warm, not hot
• 1 large squirt of dish soap — about 1 tablespoon
• Food colouring — optional, for coloured foam
• A measuring cup and spoons
• A large tray or baking dish — to catch the foam
• Safety glasses — hydrogen peroxide can irritate eyes; everyone present wears them
• For Variable 2: a raw potato — grated finely
Let’s Investigate
1
Make your prediction
Before you touch anything, write down your theory.
You have three ingredients: hydrogen peroxide, dish soap, and dry yeast. What do you think each one is doing?
3
Wake up the yeast
In your measuring cup, mix 1 tablespoon of dry yeast with 3 tablespoons of warm water.
Stir for about 30 seconds. The yeast is now active — you might see it starting to look a little frothy.
This is the escape artist getting ready.
5
Check your prediction
Go back to what you wrote in Step 1.
Was your theory right? What was the yeast actually doing — was it adding something, removing something, or speeding something up?
Write one sentence that corrects or confirms your original prediction.
2
Prepare the bottle
Pour 120mL (½ cup) of hydrogen peroxide into the bottle.
Add a large squirt of dish soap and swirl very gently to mix — do not shake.
If you want coloured foam, add a few drops of food colouring now and swirl gently.
4
Start the reaction
Pour the yeast mixture into the bottle and step back immediately.
Do not put your face over the bottle. Watch what happens. Record: how fast does it start?
How long does it keep going? When it slows down, carefully touch the outside of the bottle. What do you notice about the temperature?
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Every experiment follows The Crazy Scientist Lab Learning System™ — a simple way to help kids think like real scientists.
We
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LINK to what they already know,
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ACTIVATE curiosity through hands-on discovery
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BUILD understanding that actually sticks.
Inside every bottle of hydrogen peroxide, a gas is slowly escaping. You cannot see it. You cannot hear it. But right now, wherever that bottle is sitting, the liquid is very gradually breaking down into water and oxygen gas.
Normally that process takes days. You are about to make it happen in seconds — using something that is technically alive.
Before you set anything up: what do you think the yeast is actually doing to cause this? Is it adding something? Removing something? Creating a new substance? Write your theory before you touch anything.
You touched the bottle and it felt warm. A reaction that releases heat is called an exothermic reaction. Where did that heat energy come from — and what does that tell you about the hydrogen peroxide before and after the reaction?
The yeast made the reaction happen much faster — but the yeast itself was not destroyed. It is still there in the foam. If the yeast is not used up, what exactly is it doing? Draw a diagram showing your theory of what the yeast did to the hydrogen peroxide.
Pour a small amount of hydrogen peroxide onto a piece of fresh raw potato. What happens? Compare it to what happened with yeast. What does this tell you about what is inside a potato?
You tested yeast and potato. Both made the reaction go. What do yeast and potato have in common — and what does that tell you about where this enzyme is found in nature? Can you think of other living things that might also have it?
A catalyst is something that speeds up a reaction without being used up. Catalysts are used in car exhaust systems to break down harmful gases, and in industrial factories to make chemicals more efficiently.
Based on what you have seen today, explain in your own words why a catalyst is so useful — and why it matters that it is not used up.
"Want the full teacher guide? The Crazy Scientist Lab includes classroom delivery tips, how to manage the WOW moment, differentiation for Stage 2 & 3, — ready to teach tomorrow."
Think Like a Scientist
Scientists don't just do ONE experiment; they change one part of the experiment (independent variable) and then see how it affects another part of the experiment
(dependent variable)
Change ONE variable and test again.
Does the amount of yeast change the reaction — does more yeast produce more foam or a faster eruption, and is there a point where adding more yeast makes no difference?
Does the source of the enzyme change the result — does grated raw potato produce the same reaction as dry yeast, a bigger one, or a smaller one?
🧪 Try it! Change ONE thing and test again. What did you discover?
Dr Puddledrip’s Science Tip
Want to go deeper? Tap a section below to explore. ▼
The Science Behind It
What’s Really Happening?
Something was trapped inside the bottle.
Not a genie…
but a gas.
Normally that gas escapes very slowly, so slowly that you would never notice it.
When you added the yeast, the reaction suddenly sped up and the gas was released much faster.
The dish soap trapped the gas in thousands of tiny bubbles, creating the giant tower of foam.
Why Did The Bottle Feel Warm?
Did you notice the bottle becoming warm?
Some chemical reactions release heat while they happen.
The foam wasn’t the only clue that something was changing inside the bottle.
The warmth was another clue.
Scientists use observations like bubbles, temperature changes and colour changes to help understand what is happening during a reaction.
Curious Minds Want To Know…
Would warm yeast work faster than cold yeast?
What happens if you use more yeast?
Can other living things make the same reaction happen?
Could you make an even bigger Chemical Genie?
Try next
• Discover another chemical reaction hidden inside a living thing → [The Starch Detective]
• Look at what foam actually is and how its structure forms → [Soap Foam]
Extension: G&T Years 5 & 6
What is an enzyme?
An enzyme is a special type of protein — a large molecule made of folded chains of amino acids — that acts as a biological catalyst. The key feature of an enzyme is its three-dimensional shape.
Each enzyme has a specific region called the active site, which is shaped to fit only one particular type of molecule (called the substrate). When the substrate fits into the active site — like a key fitting a lock — the enzyme triggers a chemical reaction that breaks the molecule apart or joins molecules together.
The enzyme itself is unchanged at the end and can immediately work on the next substrate molecule. One catalase enzyme can process millions of hydrogen peroxide molecules per second.
Vocabulary
Enzyme
A special protein inside living things that speeds up a specific chemical reaction. Each enzyme is shaped to work on one particular substance only.
Catalyst
Something that speeds up a chemical reaction without being used up or changed itself. Enzymes are biological catalysts made by living things.
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TOMORROW?
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What do I do with fast finishers?
What misconceptions will they have?
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What syllabus outcomes does it cover?
What do I say when they ask WHY?
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