what hypothesis of elephant toothpaste

Elephant Toothpaste Science Experiment

Elephant Toothpaste anyone? Although elephants might not be too excited about the idea, your kids will be thrilled with the fun chemical reaction of this super simple science experiment.

With only a few common items that you probably already have at home, kids can see the quick and impressive results of the chemical reaction, feel the heat released from the process, and even play with the “elephant toothpaste” foam afterward.

Below you’ll find detailed and printable instructions, a materials list, a demonstration video, and an easy to understand explanation of why it works!

JUMP TO SECTION: Instructions | Video Tutorial | How it Works

Supplies Needed

• 2 Tablespoons Warm Water
• 1 Teaspoon Yeast
• Food Coloring
• Hydrogen Peroxide – Either 3% or 6%
• Empty Plastic Bottle

Helpful Tip: You can find the 3% at most stores, but you will need to either go to a Beauty Supply Store or order the 6% online. In the video I perform the experiment two ways. Once using the 3% peroxide and once using the 6%. It is often recommended to use 6% peroxide, but we actually preferred the reaction that happened with the 3% better.

Elephant Toothpaste Science Lab Kit – Only $5

Use our easy Elephant Toothpaste Science Lab Kit to grab your students’ attention without the stress of planning!

It’s everything you need to  make science easy for teachers and fun for students  — using inexpensive materials you probably already have in your storage closet!

Elephant Toothpaste Experiment Instructions

Step 1 –  Combine two tablespoons of warm water with one teaspoon of yeast and mix until the yeast is completely dissolved in the water. 

Step 2 –  Pour 1/2 cup hydrogen peroxide into the empty bottle. You’ll see here that we have two bottles. The bottle pictured on the left is being filled with 3% hydrogen peroxide while the bottle pictured on the right is filled with 6% hydrogen peroxide.

Step 3 –  Add a few drops of food coloring into the bottle. Take a moment to make a few observations. What happened when you added the drops of food coloring?

Note: This step is optional, but adding the color adds a fun element to the experiment. You’ll see that we used a different color of food coloring for each bottle. 

Step 4 – Next, add a squirt of dish soap into the bottle. Again, take a moment observe what happened. Did adding the dish soap appear to have any effect on the liquid already in the bottle?

Step 5 – Finally, pour the mixture of water and yeast into the bottle. Watch carefully and observe what happens. 

Helpful Tip: You may need to gently swirl the bottle in order to get the items to completely combine. We had to do that for the 6% hydrogen peroxide.

Sit back and watch what happens. Write down your observations as you watch the experiment. Can you describe what happens when you add the water and yeast mixture to the bottle. If you are using both the 3% and the 6% hydrogen peroxide like we are, is there a difference between what happens? 

Wondering what caused the liquid to react that way? Find out the answer in the how does this experiment work section below.

Video Tutorial

Watch the Elephant Toothpaste Science Experiment Step by Step Instructions Video

How Does the Elephant Toothpaste Science Experiment Work

This experiment shows a very impressive and fast chemical reaction! Hydrogen peroxide is a combination of hydrogen and oxygen (H2O2). In this experiment, yeast is a catalyst that helps release oxygen molecules from the hydrogen peroxide solution.

A catalyst is a material that increases the rate of a reaction without itself being consumed

The release of oxygen molecules in this experiment happens FAST! The foam created in this chemical reaction is made up of very tiny oxygen bubbles. These bubbles result when hydrogen peroxide (H2O2) is broken down by the yeast into water (H2O) and oxygen (O2).

During the reaction, feel the bottle. It will feel warm to the touch because it is an exothermic reaction .

An exothermic reaction is a chemical reaction that releases energy through light or heat (in this case, heat).

The reaction will continue and foam will be produced until all of the hydrogen peroxide (H2O2) has been broken down into water (H2O) and oxygen (O2).

**Have fun playing with the foam after the experiment is over! It is safe to touch because all that foam is just soap, water and oxygen. Let your kids have some fun with the foam too. Just be sure to have a towel handy!

Other Ideas to Try

Try adding more or less yeast when doing the experiment again. How does this affect the amount of foam produced?

Try the experiment again, but change the size of the bottle. How does this affect the amount of foam produced?

I hope you enjoyed the experiment. Here are some printable instructions:

• Hydrogen Peroxide – Either 3% or 6%

Instructions

• Combine two tablespoons of warm water with one teaspoon of yeast and mix until the yeast is completely dissolved in the water.
• Pour 1/2 cup hydrogen peroxide into the empty bottle
• Add a few drops of food coloring into the bottle
• Add a squirt of dish soap into the bottle
• Pour the mixture of water & yeast into the bottle
• Sit back and watch what happens

Reader Interactions

February 7, 2016 at 8:13 pm

do it was a cemical reacin

February 8, 2016 at 1:15 pm

Correct! The yeast is mixed with the hydrogen peroxide causes a chemical reaction.

Which version did you like better, the one that reacted fast or the one that reacted slow?

May 17, 2018 at 12:31 pm

Looks amazing! What is the chemical reaction?

March 24, 2019 at 10:40 am

I’m am going to do that science project and this was super helpful thanks so much

March 24, 2019 at 10:46 am

Thank you so much I am doing this science project and I don’t know what to do and now I know what to do j

September 1, 2019 at 8:09 am

Did you try using more yeast or more 3 % hydrogen peroxide?

Found this explanation: “The yeast acted as a catalyst; a catalyst is used to speed up a reaction. It quickly broke apart the oxygen from the hydrogen peroxide. Because it did this very fast, it created lots and lots of bubbles. Did you notice the bottle got warm. Your experiment created a reaction called an Exothermic Reaction – that means it not only created foam, it created heat! The foam produced is just water, soap, and oxygen ” The yeast is not reacting with the hydrogen peroxide. Rather it is acting as a catalyst. A catalyst is a substance that causes a chemical reaction to speed up but is not “used” up during the reaction. Hydrogen Peroxide: H2O2 hydrogen and oxygen Baker’s Yeast: C19H14O2 carbon, hydrogen and oxygen

August 18, 2020 at 2:25 pm

My son did this experiment which was great! The only problem was that he played with the foam afterwards and his hands got super itchy. Can you be allergic to the yeast? Just a warning in case this happens to anyone else.

August 11, 2023 at 8:49 pm

Yeah I did this with potassium iodide and 25% hydrogen peroxide in a lab and my fingers went a little white on the tips (I had gloves on after this happened) they did get itchy and I think it was just the hydrogen peroxide bleaching the skin. This is an exothermic reaction so it can get hot not sure how hot with yeast.

January 25, 2022 at 11:25 am

It did not work for me and i don’t know why maybe caused i used rubbing alcohol insted

December 6, 2023 at 3:55 pm

good helpful and fun

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Elephant toothpaste

If an elephant used toothpaste, this is probably what it'd look like! Learn about chemical reactions by watching this heat-producing mixture bubble and overflow for up to half an hour. The experiment comes from pages of the Nat Geo Kids book Try This! Extreme .

DON'T FORGET YOUR SAFETY EQUIPMENT: safety goggles, lab apron, nitrile gloves

Stand the soda bottle in a pan.

Insert funnel in neck of soda bottle.

Add ½ cup peroxide, detergent, and food coloring.

UM, DID YOU SEE THE WARNING ABOVE? Check it out again!

In measuring cup, beaker, or plastic cup, combine yeast and warm water. Combine with plastic spoon.

Pour yeast mixture into soda bottle and remove funnel.

WARNING: In case you missed it the first time, avoid touching or getting the chemicals on skin or clothing. And don't get too close, as heat and steam can be dangerous.

WHAT'S GOING ON

Hydrogen peroxide normally decomposes (breaks down into separate elements), and combining it with detergent and yeast (a catalyst) speeds up the process.

As the oxygen emanates from the reaction, it creates bubbles. The detergent speeds up the foaming. The reaction is "exothermic," meaning it produces heat as well as steam.

WARNING:  This experiment uses chemicals that can irritate skin and damage clothes, so make sure to use safety goggles, lab apron, and nitrile gloves. Avoid touching or getting the chemicals on skin or clothing. And don't get too close, as heat and steam can be dangerous.

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Science News Explores

Level up your demonstration: make it an experiment.

With a few tweaks — and many replications — any demonstration can become an experiment

Simple chemistry can make fountains of foam. If you want to do an experiment, though, you’ll need to make more than one.

SDI Productions/iStock/Getty Images Plus

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• Google Classroom

By Bethany Brookshire

April 27, 2021 at 6:30 am

Science demonstrations can be real crowd pleasers. In fact, Camille Schrier won the 2020 Miss America crown after performing a science demonstration during the talent portion of the competition. On stage, she mixed common chemicals to create massive mountains of steaming foam — a trick often called “elephant toothpaste.” It wowed the judges. But as she said when she performed it, this was a demonstration. It wasn’t an experiment. But you can turn that, or any demonstration, into an experiment.

Start by finding a hypothesis . This a statement that you can test. How do you find a hypothesis? You can begin by learning more about how a specific scientific demonstration works. By breaking it down into its parts, you might be able to find a statement to test. And from there, you can design your experiment.

Elephant toothpaste explained

Let’s look at the elephant toothpaste demonstration . There are four ingredients: hydrogen peroxide, dish soap, food coloring and a catalyst. Hydrogen peroxide (H 2 O 2 ) is a chemical people can use to clean wounds or surfaces and bleach them. It slowly breaks down when exposed to light, forming water and oxygen

This is where the catalyst comes in. A catalyst is something that speeds up a chemical reaction. In the elephant toothpaste experiment, yeast or potassium iodide can be used as a catalyst. Either will cause the hydrogen peroxide to break down very quickly.

The dish soap and food coloring aren’t needed for the reaction. But they create the show. As hydrogen peroxide breaks down into water and oxygen, the dish soap will catch the liquid and gas to form bubbles. It’s the source of the foam. The food coloring gives the foam its bright color.

Now that we know what’s happening, we can start asking questions. How much hydrogen peroxide should you use? How much catalyst? How much dish soap? Those are all good questions. In fact, they’re each the beginning of a hypothesis.  

Let’s focus on hydrogen peroxide. If the hydrogen peroxide breaks down into the water and oxygen that power the foam, then perhaps more hydrogen peroxide would produce more foam. That gives us a hypothesis: More hydrogen peroxide will produce more foam .

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Demo to experiment

We can now design an experiment to test that hypothesis. First, identify the variable that you will be testing. Here, our hypothesis is about hydrogen peroxide. So the experiment needs to change the proportion of hydrogen peroxide in the elephant toothpaste.

An experiment also needs a control — a part of the experiment where nothing changes. The control could be no hydrogen peroxide (and no foam). The experiment could then test different amounts of hydrogen peroxide to see which produces the most foam.

You will have to measure the outcome of any experiment. For elephant toothpaste, you might measure the height of the foam using video recordings. Or you could measure the mass of your container before and after the reaction, to see how much foam exploded out. This would be different for every experiment. For an experiment involving plants, you could measure plant height or the size of any fruit. When growing rock candy, you could weigh the final product .

Running the experiment just once isn’t enough. You need to repeat it many times , step by step, over and over. Any single result could have been due to some accident. Repeating the experiment again and again cuts the chance you will see a difference by mistake. Write down all the results very carefully. It helps to keep a lab notebook .

Finally, you will want to compare results. This may mean running statistical tests on your data. These are mathematical tests that can help you interpret your findings. They might show you that more hydrogen peroxide does indeed produce more elephant toothpaste. Or the results might show something else. Maybe there’s just the right amount of hydrogen peroxide, and too much doesn’t produce any more foam.

If you want to find out, though, don’t do a demonstration. Test it through an experiment.

For more ideas, check out our experiments collection . We’ve made experiments out of the five-second rule , baking soda volcanoes , sneezing out snot and much more.

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How to Make Elephant Toothpaste

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As we all know, elephants probably don't brush their teeth. But if they did, they probably wouldn't use elephant toothpaste. It's really fun to make, though.

Imagine shaving cream shooting out of a volcano you made for the science fair. That's the satisfaction that comes with the foaming chemical reaction produced when you mix dish soap, hydrogen peroxide and dry yeast ― and the good news is, you can make it in your home. You know, if nobody minds you making a gigantic mess.

The elephant toothpaste reaction is just the speeding-up of a chemical reaction that usually happens very slowly. Hydrogen peroxide ― that antiseptic liquid that usually comes in a brown bottle and bubbles up when you put it on a cut ― is a chemical compound that's made of two hydrogen and two oxygen molecules bonded together. The chemical formula for hydrogen peroxide is H 2 O 2 , which might sound a bit familiar because it's very close to the most famous chemical compound of all time ― H 2 O, or plain old water. In fact, hydrogen peroxide, if left to its own devices, will sit around quietly decomposing into water and an extra oxygen atom ― especially when exposed to sunlight, which is why it comes in a dark brown bottle. But elephant toothpaste provides a way to see this chemical decomposition happen very quickly and dramatically.

The way to speed it up is to murder some yeast. These tiny organisms, like nearly all living things, contain an enzyme called catalase that acts as a catalyst for the reaction. Once the hydrogen peroxide comes in contact with the yeast, it starts splitting into water and oxygen gas at an alarming rate. The thing is, this reaction doesn't look like much unless you add the third ingredient: dish soap.

Because the oxygen gas released by decomposing H 2 O 2 just forms delicate bubbles that pop when they get to the surface, the spectacle of elephant toothpaste requires a little something extra to give the bubbles surface tension. Adding liquid soap preserves the bubbles and turns them into a rapidly proliferating foam.

Elephant Toothpaste Recipe

So, are you ready to make some elephant toothpaste? Great! You'll need:

• 1/2 cup (4 fluid ounces, or 12 millilters) hydrogen peroxide. There are several different recipes online, but most agree that you get the best reaction with the 12 percent hydrogen peroxide solution (called "V40 developer") you can find at beauty supply stores ― the kind you use to bleach hair. That said, if you're trying this with children, it might be safer (although less exciting) to use the 3 percent H 2 O 2 you get in the brown bottle at the pharmacy, as the stronger stuff can really irritate skin and eyes. Of course, none of this stuff should be ingested.
• One packet of dry yeast granules you can find in the baking section of the grocery store.
• A giant dollop of dish soap.
• Food coloring, for flair, though this is optional.
• Warm water to activate the yeast.
• Protective eye gear like safety goggles or even your own eyeglasses. Gloves and an apron also would be a good idea.
• A container ― any bottle with a narrow neck will show off the elephant toothpaste reaction to its best advantage.
• A pan to catch your results, though a bathtub would be a smart place to do this experiment.

Follow the activation directions on the packet of yeast, adding warm water and waiting until it begins to fizz. Pour the hydrogen peroxide into the bottle first, adding a couple drops of food coloring if you wish, and a generous squirt of dish soap. Pour the yeast mixture in last, and watch it blast off!

Please don't cap the bottle, and please don't try to use this toothpaste on your own teeth!

If you like elephant toothpaste, you might really like the Mentos and Coke explosion .

Elephant Toothpaste FAQ

How do you make elephant toothpaste, can you use 3 percent hydrogen peroxide for elephant toothpaste, what is the meaning of elephant toothpaste, what kind of hydrogen peroxide do you need for elephant toothpaste, what causes elephant toothpaste to explode.

Please copy/paste the following text to properly cite this HowStuffWorks.com article:

Elephant Toothpaste Explosion Experiment

Categories Science Experiments

We are big fans of creative STEM activities and science experiments for kids, which is why it’s a bit surprising that it’s taken us this long to do the classic elephant toothpaste explosion experiment!

The real reason is that this elephant toothpaste STEM project requires one sort of weird material- more concentrated hydrogen peroxide that is used to bleach hair.

Keep reading to find out how to transform this classic science demonstration into a real science lesson and STEM activity. If you love this activity, you’ll also like our entire unit of circus STEM activities!

If you’re like us, and have never tried this chemistry science experiment before, it’s super fun!

Kids love it and it’s an easy way to show how exothermic reactions work while still being relatively touch-safe.

What is the Purpose of Elephant Toothpaste?

Elephant toothpaste is nothing like toothpaste and it certainly isn’t meant for elephants.

I’m not sure where the elephant toothpaste description came from, except that when it comes out of a bottle, it looks a bit like toothpaste (particualrly if you dye it blue), and it’s big and frothy, so I suppose it would be the size an elephant would need to brush its teeth.

Elepahant toothpaste is actually a chemical reaction between yeast and hydrogen peroxide.

How Does Elephant Toothpaste Work?

The two main ingredients in elephant toothpaste (yeast and hydrogen peroxide) create a carbon dioxide gas, which creates large air bubbles that get trapped in soap, creating a frothy mixture that is fun to look at.

Elephant toothpaste is also an example of an exothermic reaction, meaning that the chemical reaction produces heat. If you put your hand near the foam as it is first emerging, you’ll feel a slight warmth.

It is not advised for kids to touch the foam.

Elephant Toothpaste STEM Project Directions

Follow along with these directions to make your own elephant toothpaste STEM project. Remember to stay safe, some of the ingredients in this project may irritate the skin or eyes, and may bleach clothing or furniture.

Elephant Toothpaste Hypothesis

Before starting the elephant toothpaste STEM activity, have the kids create a hypothesis. What do they think will happen when the ingredients mix?

You can also make a version with and without dish soap. How do the kids think the addition of the soap will change the reaction?

Elephant Toothpaste Questions

It’s always a good idea to ask questions and get kids thinking while doing science experiments. The elephant toothpaste science experiment is a good one to use as a examination of why it’s important to stay safe in the science lab.

Here are some questions you can ask the kids while doing this experiment:

• What is a chemical reaction?
• What is an exothermic reaction?
• Why does mixing the ingredients create a chemical byproduct?
• Would using differnet ingredients have the same reaction?
• Does changing the amount of each ingredient change the reaction?
• Why is it important to stay safe during a science experiment?

Elephant Toothpaste Conclusion

Children should come up with their own conclusions when doing this experiment (you can snag a copy of our STEM worksheet below), but some conclusions might include:

• When chemicals mix, they can react
• Changing the ingredients can change the reaction
• Some chemical reactions can be dangerous
• It’s important to take safety precautions when working with chemicals

What You Need for the Elephant Toothpaste Experiment

You’ll need a few things for this experiment:

• Active dry yeast
• 4 0 Volume Hydrogen Peroxide (find it at a local beauty store if you don’t want to ship it)
• Safety goggles ( these are perfect for kids)
• Food coloring ( these are our favorites )
• Large jar or bottle
• Large plastic tray

How to Do the Elephant Toothpaste Explosion Experiment

Mix 1 tablespoon of yeast with 3 tablespoons of slightly warm water in your jar.

Add some food coloring and stir.

Add about a tablespoon of dish soap to the liquid and stir carefully, so you don’t create too much froth.

Place the jar on the tray.

Put on your safety goggles. There is a small chance you might get some of the foam in your eyes while doing this experiment, so it’s important to stay safe!

Pour about 1/2 a cup of the hydrogen peroxide into a seperate cup.

When you are ready to start the reaction, carefully pour the hydrogen peroxide into the jar and watch things happen!

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Elephant Toothpaste Experiment: How-To Plus Free Worksheet

Heat things up with this larger-than-life science lesson.

Who knew toothpaste could be so fun? While no actual toothpaste is produced, this experiment is an exciting and hands-on way to bring several science lessons to life. You’ll want to use some caution when performing it with kids. Some of the chemicals used can be irritating and the substance produced is hot, so you won’t want to actually brush anyone’s teeth with the foam, as tempting as that may be! Read on to see how to do the Elephant Toothpaste Experiment, and  fill out the form on this page  to grab your free recording sheet.

How does the Elephant Toothpaste Experiment work?

This experiment works through a chemical reaction that results from a catalyst (potassium iodide, aka yeast) being introduced into a mixture of hydrogen peroxide and dish soap. The hydrogen peroxide is decomposed into water and oxygen and the catalyst speeds up the reaction, forcing the oxygen into the soap bubbles. The resulting effect is the substance quickly pouring up and out of the container.

What does the Elephant Toothpaste Experiment teach?

This experiment is a crowd-pleaser, but it also serves to teach kids a lot. The concept of a catalyst speeding up a reaction is demonstrated in an obvious and exciting way as the introduction of the yeast forces the foam to explode up and out of the bottle. It also teaches kids about exothermic reactions as the foam coming out of the bottle is hot. Additionally, kids get to see a decomposition reaction as the rapid decomposition of hydrogen peroxide results in the release of oxygen gas.

Is there an Elephant Toothpaste Experiment video?

This video from teacher Hilary Statum will give you the step-by-step instructions for making your own Elephant Toothpaste.

Materials Needed

To do the experiment, you will need:

• 16-oz. empty plastic soda bottle
• Very warm water
• 3% hydrogen peroxide (6% is better, if available)
• Measuring cups
• Measuring spoons
• Safety glasses
• Safety gloves
• Funnel or measuring cup with a lip
• Food coloring

Our free recording sheet is also helpful— fill out the form on this page to get it!

Elephant Toothpaste Experiment steps:

1. place the bottle on a large tray and put on your safety goggles and gloves., 2. mix 1 tablespoon of yeast into 3 tablespoons of warm water until you achieve a creamy consistency. place in a small cup and set to the side., 3. use a funnel or measuring cup to pour half a cup of hydrogen peroxide into the bottle., 4. add a bit of food coloring. for a solid color, add directly into the bottle. for stripes, squirt it with the pipettes so it trickles down the sides of the inside of the bottle., 5. add approximately 1 tablespoon of dish soap to the hydrogen peroxide., 6. use a funnel or measuring cup to add the yeast mixture to the bottle., 7. step back and watch the explosion, grab our free elephant toothpaste experiment worksheet.

Fill out the form on this page to get your worksheets. The first worksheet asks kids to make a prediction about what they think will happen. They can use the provided spaces to draw or write their predictions and observations. The second worksheet lists questions for students to answer about the experiment.

Additional Reflection Questions

• Why do we add the yeast to the water?
• What do you think would happen if we added more dish soap?
• What do you think would happen if we added more yeast to the mixture?
• What is the liquid that is left in the bottle?
• Describe the reaction that occurs. How long does it last?

Can this experiment be done for a science fair?

Yes! If you want to do the Elephant Toothpaste Experiment for a science fair, we recommend switching up some of the variables. For example: Does the type or shape of the container matter? Does the type of dish soap matter? Does adding more yeast change the reaction? Form a hypothesis about how changing the variables will impact the experiment. Good luck!

Looking for more experiment ideas? Check out our  big list of experiment ideas here.

Plus, be sure to  subscribe to our newsletters  for more articles like this., you might also like.

Giant Bubbles Experiment: How-To Plus Free Worksheet

It'll blow everyone away! Continue Reading

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August 1, 2019

Make Elephant Toothpaste

A bubbly science project from Science Buddies

By Science Buddies & Ben Finio

Squeeze some science: Use a little kitchen chemistry to make a fountain of "toothpaste" almost big enough for an elephant's brush!

George Retseck

Key Concepts Chemistry Biology Reaction Catalyst Surface tension

Introduction Create a giant foaming reaction, and use science to wow your friends with this classic activity. With just a few ingredients you can make something that looks like foamy toothpaste being squeezed from a tube—but so big that it looks almost fit for an elephant!

Background You might be familiar with hydrogen peroxide as an antiseptic used to clean cuts and scrapes, which it does by killing bacteria. But what is it? It is a liquid made from hydrogen atoms and oxygen atoms (its chemical formula is H 2 O 2 ). It is available in different strengths, or concentrations. You usually find it in a 3 percent concentration (although higher concentrations are available, they are more dangerous and must be handled carefully). It also breaks down when exposed to light, which is why it usually comes in dark brown bottles. 

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When hydrogen peroxide breaks down, it turns into oxygen (O 2 ) and water (H 2 O). Normally this breakdown happens very slowly. But you can make that reaction happen faster! How? By adding a catalyst. Yeast is an organism that contains a special chemical called catalase that can act as a catalyst to help break down hydrogen peroxide. Catalase is present in almost all living things that are exposed to oxygen, and it helps them break down naturally occurring hydrogen peroxide. 

This means that if you mix yeast with hydrogen peroxide, the hydrogen peroxide will rapidly break down into water and oxygen gas. The oxygen gas forms bubbles. These bubbles would usually escape from the liquid and pop quickly. But adding a little dish soap provides additional surface tension, allowing the bubbles to get trapped and creating lots of foam. This foam looks like a giant squeeze of toothpaste—almost big enough for an elephant!

Empty plastic bottle

Dry yeast (found in the baking section of the grocery store)

Liquid dish soap

3% hydrogen peroxide

Measuring cups 

Measuring spoons

Safety glasses

Large tub or tray to catch the foam 

Location for the activity that can tolerate spills (of hydrogen peroxide as well as possibly food coloring), such as a kitchen or bathroom—or an outdoor location 

Liquid food coloring (optional)

Different-shaped bottles or glasses (optional) 

Preparation

Put on your safety glasses to do this activity because hydrogen peroxide can irritate your eyes. (Note: although the product of this activity resembles toothpaste, it is not toothpaste, so do not attempt to use it!)

Gather your materials in the location where you plan to do your activity. Place your plastic bottle on the tray or tub so that it is easy to clean up all the foam.

Measure 1/2 cup of hydrogen peroxide, and carefully pour it into the bottle.

Add a big squirt of dish soap into the bottle, and swirl gently to mix.

If you want to make your foam a single color, add a few drops of food coloring directly into the hydrogen peroxide, and swirl the bottle gently to mix. If you want to give your foam stripes like some toothpastes, put the drops along the inside rim of the bottle’s mouth. Let them drip down the inside of the bottle, but do not mix. 

In a measuring cup mix together one tablespoon of yeast and three tablespoons of warm water. Stir for about 30 seconds. 

Pour the yeast mixture into the bottle then quickly step back, and watch your reaction go! What happens? How long does the reaction last?

Extra: Try the activity without the dish soap. What happens? How was the result different?

Extra: Try the activity with different-shaped containers. What happens if you use a bottle with a narrower or wider neck—or a cylindrical drinking glass with no neck?

Observations and results You probably saw lots of bubbles and foam in this activity. What makes the foam appear? When the hydrogen peroxide comes into contact with the yeast it starts breaking down into water and oxygen. Oxygen is a gas and therefore wants to escape the liquid. The dish soap that you added to your reaction, however, traps these gas bubbles, forming a foam. The reaction continues as long as there is some hydrogen peroxide and yeast left. Once one of them runs out it stops making new foam. If you tried the activity without dish soap, the reaction probably will still made bubbles—but not foam. 

Cleanup Wash the foam down the sink when you are done with the activity. 

More to Explore Enzymes, Foam and Hydrogen Peroxide , from Science Buddies Exploring Enzymes , from Scientific American The Liver: Helping Enzymes Help You , from Scientific American Erupting Diet Coke with Mentos , from Science Buddies Yeast Alive! Watch Yeast Live and Breathe , from Scientific American STEM Activities for Kids , from Science Buddies 

This activity brought to you in partnership with Science Buddies

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Fantastic foamy fountain.

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You will need.

• A clean 16 ounce (473 ml) plastic soda bottle or a water bottle.
• 20-Volume hydrogen peroxide liquid (20-volume is a 6% solution that is stronger than what you find in most pharmacies. It is typically used for lightening hair and is found at many beauty supply stores. You can use the 3% hydrogen peroxide found in pharmacies, but the reaction will be a bit smaller)
• 1 Tablespoon (15ml –  one packet) of dry yeast
• 3+ Tablespoons (15 ml) of warm water
• Liquid dishwashing soap
• Food coloring
• Safety goggles

NOTE: The foam could overflow from the bottle, so be sure to do this experiment on a washable surface, or place the bottle on a tray.

CAUTION: The unreacted hydrogen peroxide can irritate skin and eyes. Read the safety information on the hydrogen peroxide bottle and be sure to wear safety goggles.

• Use a funnel to carefully pour 3/4 cup (180 ml) of the hydrogen peroxide liquid into the bottle
• Add about 10 drops of your favorite food coloring into the bottle.
• Add about 1 tablespoon (15ml) of liquid dish soap into the bottle and swish the bottle around a bit to mix it.
• In a separate small cup, combine the warm water and the yeast together and mix for about 30 seconds. It should be about the consistency of melted ice cream – add a bit more warm water if needed.
• Now the adventure starts! Use the funnel to pour the yeast-water mixture into the bottle and watch the foaminess begin!

Can I touch the foam? The reaction typically breaks down the hydrogen peroxide so you are left with mostly just soapy water and yeast. There can, however, be un-reacted peroxide which could irritate skin and eyes. For that reason, it is recommended you do not touch the foam.

(If you use the 3% hydrogen peroxide found in most pharmacies, then the foam can be touched safely.)

How does it work?

Foam is awesome! The foam you made in this classic Elephant’s Toothpaste reaction is extra-special because each tiny foam bubble is filled with oxygen. The yeast acted as a catalyst; a catalyst is used to speed up a reaction.  It quickly broke apart the oxygen from the hydrogen peroxide. Because it did this very fast, it created lots and lots of bubbles. Did you notice the bottle got warm? Your experiment created a reaction called an Exothermic Reaction – that means it not only created foam, it created heat! The foam produced is just water, soap, and oxygen so you can clean it up with a sponge and pour any extra liquid left in the bottle down the drain.

This experiment is sometimes called “Elephant’s Toothpaste” because it looks like toothpaste coming out of a tube, but don’t get the foam in your mouth!

Make it an experiment:

The project above is a DEMONSTRATION. To make it a true experiment, you can try to answer these questions:

• Does the amount of yeast change the amount of foam produced?
• Will the experiment work as well if you add the dry yeast without mixing it with water?
• Does the size of the bottle affect the amount of foam produced?

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Elephant's Toothpaste

Elephant toothpaste.

This demonstrations is called Elephant’s Toothpaste because the chemical reaction produces a large foamy mess that looks like toothpaste squirting out of a tube. It is so big that only an elephant could use toothpaste this large. It is, of course, not toothpaste so please do not try to brush your teeth with it! The kids safe version below is harmless but certainly wouldn’t taste very good.

Our EXTREME Scientists do the Elephant’s Toothpaste demonstration in our  Extreme Science Theater  located on the lower level of the science center. So if you want to see it again just come on in!

What is Elephant Toothpaste?

This large demonstration uses hydrogen peroxide (H 2 O 2 ), sodium iodide (NaI) and soap. First we pour in the hydrogen peroxide, then the soap and finally the sodium iodide.

The hydrogen peroxide used in the demonstration is 30% hydrogen peroxide. This is 10 times stronger than the hydrogen peroxide that you have in your medicine cabinet. That is usually 3% hydrogen peroxide, and your local salon probably uses 6%. The 30% hydrogen peroxide is not something you would put on a cut or scrape, but it works perfectly for this demonstration. The sodium iodide reacts with the hydrogen peroxide (H 2 O 2 ) by removing an oxygen atom. This essentially produces water and oxygen gas (H 2 O + O2). The oxygen gas produced gets trapped in the soap which produces the big ball of foam. The reaction produces oxygen gas, water and iodine. That is why the foam has a yellow color. If you were to touch this foam, your hand would be stained yellow just as if you put iodine on your skin.

Since you can’t get these materials at home we have a Kids Safe version of this demonstration that you can do at home or in the classroom! Do this at your next family night, slumber party or birthday party. It is fun, safe and cool to watch.

Kid-Safe Elephant Toothpaste

What you need:

12 oz plastic bottle

hydrogen peroxide (3%)

baking sheet

What to do:

Prepare yeast solution by adding dry yeast to warm water and wait a few minutes until it becomes frothy.

Pour 2 inches of hydrogen peroxide (3%) into the bottle.

Place bottle on baking sheet.

Squeeze in a good squirt of dish soap.

Pour in yeast solution (3 tablespoons).

The Science:

The yeast contains an enzyme called Catalase that breaks down hydrogen peroxide (H 2 O 2 ) into oxygen gas and water. The oxygen gas gets trapped by the soap, and you get a large foamy solution that squirts out of the top of the bottle!

The cool thing about this activity is that the enzyme Catalase can also be found in potatoes, dogs and even us! We have the same enzyme in our bodies. That is why you see the 3% hydrogen peroxide bubble when you put it on a cut or scrape. The oxygen released is what kills the germs in the cut. We have this enzyme because we naturally produce low amounts hydrogen peroxide as a byproduct of oxidative metabolism (the way that a cell gains useful energy). Our cells need energy, but low amounts of hydrogen peroxide are produced and need to be neutralized through enzymes like Catalase.

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Elephant Toothpaste – Two Ways to Make It

Elephant toothpaste is a chemical reaction that makes a volcano of foam when soapy water traps gases from the rapid decomposition of hydrogen peroxide. There are two easy methods for making elephant toothpaste. One makes a giant mountain of foam, while the other produces a smaller effect but is safe enough for kids to touch. The dramatic reaction uses strong peroxide and potassium iodide, while the kid-friendly version uses dilute peroxide and replaces potassium iodide with yeast. Here are instructions for both methods and a look at the chemistry involved.

Why Is It Called Elephant Toothpaste?

First, you may wonder why the reaction has the name “elephant toothpaste.” It’s because the thick column of foam escaping a tube looks like toothpaste big enough for an elephant to use. Also, it’s a lot easier and more descriptive than calling the reaction “rapid decomposition of peroxide”. After all, the point of elephant toothpaste is engaging people in the wonder of science. Even if someone doesn’t understand the chemistry, the project is fun and entertaining.

How to Make Giant Elephant Toothpaste

When you see videos of the world’s largest elephant toothpaste, you’re viewing the classic version of the demonstration.

This version uses concentrated hydrogen peroxide, potassium iodide or sodium iodide, liquid dishwashing detergent, water, and (if desired) food coloring:

• 30% hydrogen peroxide (H 2 O 2 )
• Potassium iodide (KI) or sodium iodide (NaI)
• Liquid dishwashing detergent
• Food coloring (optional)
• Large graduated cylinder or Erlenmeyer flask
• Tray or tarp to catch the foam

The chemicals are available online, although it’s easier to just pick up the peroxide at a beauty supply store. Choose any tall container for the demonstration, but use glass and not plastic because the reaction generates heat.

Start by putting on proper safety gear, including safety goggles and gloves.

• First, prepare a saturated solution of potassium iodide or sodium iodide in water. In a beaker, dissolve crystals of either chemical in about 120 ml (4 ounces) of water. Continue stirring in the solid until no more dissolves. It takes about a tablespoon of the dry chemical. But, measurements are not critical here. Set aside the solution for now.
• Set the cylinder or flask in a tray or on a tarp. Pour about 60 ml (2 ounces) of 30% hydrogen peroxide into the glass tube. Add a squirt (about 5 ml) of dishwashing liquid to the tube. If you want colored foam, add a few drops of food coloring. Swirl the liquids to mix them. Here again, exact measurements are unnecessary.
• When you’re ready for the reaction, pour about 15 ml (one tablespoon) of the iodide solution and stand back. Foam forms within seconds and rapidly escapes the tube.
• After the reaction ends, wash the contents of the tray and tube down the drain with water.

Kid-Friendly Elephant Toothpaste

The classic chemistry demonstration is for chemistry educators, but the kid-friendly elephant toothpaste is safe enough for parents and children to perform and touch. Also, this version uses easy-to-find ingredients.

• 3% household peroxide
• 1-2 packet of dry yeast
• Food coloring
• Empty plastic soft drink bottle
• Cookie sheet or pan to catch the foam (optional)

It’s not necessary to don safety gear for this reaction and it’s fine to use either a plastic or glass container. Just make sure the bottle has a narrow opening because this channels the foam and improves the effect.

Don’t worry about measuring ingredients precisely.

• Pour about a cup of 3% hydrogen peroxide into an empty bottle. If the bottle opening is small, use a funnel.
• Add a couple of squirts of dishwashing liquid and a few drops of food coloring to the bottle. Swish the liquid around to mix it.
• In a separate container, mix together yeast with enough warm water that the liquid is easy to pour. A paper cup is a great container choice because you can pinch its rim and make pouring the yeast mixture easier. Wait a couple of minutes before proceeding so the yeast has a chance to activate.
• When you’re ready, place the bottle on a cookie sheet or pan and pour yeast mixture into the bottle
• Clean-up using warm, soapy water.

Is Elephant Toothpaste Safe to Touch?

You can handle the ingredients and the foam from the kid-friendly elephant toothpaste project. However, don’t touch either the ingredients or the foam from the classic giant elephant toothpaste. This is because the peroxide is concentrated enough to cause a chemical burn, while the giant toothpaste is hot enough to cause a thermal burn.

How Elephant Toothpaste Works

The basis for the elephant toothpaste display is the rapid decomposition of hydrogen peroxide (H 2 O 2 ). Hydrogen peroxide naturally decomposes into water and oxygen gas according to this chemical reaction:

2H 2 O 2 (l) → 2H 2 O(l) + O 2 (g)

In a decomposition reaction , a larger molecule breaks down into two or more smaller molecules. The normally slow progression of the reaction is why a bottle of peroxide has a shelf life . Exposure to light accelerates the decomposition, which is why peroxide comes in opaque containers.

Either potassium iodide or the enzyme catalase (found in yeast) acts as a catalyst for the reaction. In other words, either of these chemicals supercharges the reaction so it proceeds very quickly. Breaking chemical bonds in peroxide releases a lot of energy. Only a fraction of this energy goes back into forming chemical bonds making water and oxygen. What this means is that elephant toothpaste is an exothermic reaction or one that releases heat. How hot the reaction gets depends on how much peroxide you start with and how efficiently the catalyst speeds up the reaction. So, the classic version of the project gets hot enough to steam. The kid-friendly version of elephant toothpaste gets warm, but not hot enough to cause a burn.

Producing gas isn’t enough to make a foamy volcano. Adding liquid soap or dishwashing detergent to the mixture traps the gas bubbles. Normally, the reaction doesn’t have much color. Using food coloring makes the foam more interesting. Depending on your choice of colors, it also makes the foam resemble toothpaste.

• Dirren, Glen; Gilbert, George; Juergens, Frederick; Page, Philip; Ramette, Richard; Schreiner, Rodney; Scott, Earle; Testen, May; Williams, Lloyd. (1983).  Chemical Demonstrations: A Handbook for Teachers of Chemistry. Vol. 1.  University of Wisconsin Press. Madison, Wisconsin. doi:10.1021/ed062pA31.2
• “ Elephant’s Toothpaste .”  University of Utah Chemistry Demonstrations . University of Utah.
• Hernando, Franco; Laperuta, Santiago; Kuijl, Jeanine Van; Laurin, Nihuel; Sacks, Federico; Ciolino, Andrés (2017). “Elephant Toothpaste”.  Journal of Chemical Education . 94 (7): 907–910. doi: 10.1021/acs.jchemed.7b00040
• IUPAC (1997). “Chemical decomposition”. Compendium of Chemical Terminology (the “Gold Book”) (2nd ed.). Oxford: Blackwell Scientific Publications. ISBN 0-9678550-9-8. doi: 10.1351/goldbook

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Elephant’s toothpaste.

Explore the science of this explosive elephant toothpaste experiment, and try your own version at home.

Experiment with some enormous ‘toothpaste’, fit for an elephant.

Hydrogen peroxide (H2O2) decomposes naturally into water (H2O) and oxygen (O2). By adding a few more ingredients we can make a huge, bubbly reaction to visualise this process. In this experiment we add dish soap, to help create bubbles, and a catalyst — which is a special chemical that allows us to fast forward a reaction.

We’ve used two different concentrations of hydrogen peroxide to show how the strength of a chemical can change the size of the reaction, but you can easily try this experiment at home with just a few household ingredients.

IMPORTANT: Please note, if you try this experiment at home you need to use hydrogen peroxide bleach, NOT a chlorine-based bleach.

What you’ll need:

• Empty plastic bottle
• 1/4 cup of dishwashing liquid
• 1/2 cup of 3% hydrogen peroxide
• Packet of active yeast

Instructions

• Pour the dishwashing liquid and hydrogen peroxide into your bottle.
• Activate the yeast by stirring in a little warm water, waiting at least 10 minutes for the yeast to “wake up”. The yeast mixture is ready when the yeast has dissolved and the liquid starts bubbling. This will be the catalyst for this reaction.
• When you’re ready to start the experiment, add the yeast and watch how quickly the reaction occurs!

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Elephant Toothpaste Chemistry Demonstration

A fun science experiment that looks like pachyderm dental care

Jasper White / Getty Images

• Ph.D., Biomedical Sciences, University of Tennessee at Knoxville
• B.A., Physics and Mathematics, Hastings College

The dramatic elephant toothpaste chemistry demonstration produces copious amounts of steaming foam that looks like the kind of toothpaste an elephant might use to brush his tusks. To see how to set up this demo and learn the science of the reaction behind it, read on.

Elephant Toothpaste Materials

The chemical reaction in this demonstration is between the hydrogen peroxide and a solution of potassium iodide and dishwashing detergent that captures the gases to make bubbles.

• 50-100 ml of 30% hydrogen peroxide (H 2 O 2 ) solution (Note: This hydrogen peroxide solution is much more concentrated than the kind you'd generally purchase at a pharmacy. You can find 30% peroxide at a beauty supply store, science supply store, or online.)
• Saturated potassium iodide (KI) solution
• Liquid dishwashing detergent
• Food coloring
• 500 mL graduated cylinder
• Splint (optional)

For this demonstration, it's advisable to wear disposable gloves and safety glasses. Since oxygen is involved in this reaction, do not perform this demonstration near an open flame. Also, the reaction is exothermic , producing a fair amount of heat, so do not lean over the graduated cylinder when the solutions are mixed. Leave your gloves on following the demonstration to aid with cleanup. The solution and foam may be rinsed down the drain with water.

Elephant Toothpaste Procedure

• Put on gloves and safety glasses. The iodine from the reaction may stain surfaces so you might want to cover your workspace with an open garbage bag or a layer of paper towels.
• Pour ~50 mL of 30% hydrogen peroxide solution into the graduated cylinder.
• Squirt in a little dishwashing detergent and swirl it around.
• You can place 5-10 drops of food coloring along the wall of the cylinder to make the foam resemble striped toothpaste.
• Add ~10 mL of potassium iodide solution. Do not lean over the cylinder when you do this, as the reaction is very vigorous and you may get splashed or possibly burned by steam.
• You may touch a glowing splint to the foam to relight it, indicating the presence of oxygen.

Variations of the Elephant Toothpaste Demonstration

• You can add 5 grams of starch to the hydrogen peroxide. When the potassium iodide is added, the resulting foam will have light and dark patches from the reaction of some of the starch to form triiodide.
• You can use yeast instead of potassium iodide. Foam is produced more slowly, but you can add a fluorescent dye to this reaction to produce elephant toothpaste that will glow very brightly under a black light .
• You can color the demonstration and make it into an Elephant Toothpaste Christmas Tree for the holidays.
• There's also a kid-friendly version of the elephant toothpaste demo that's safe for little hands.

Elephant Toothpaste Chemistry

The overall equation for this reaction is:

2 H 2 O 2 (aq) → 2 H 2 O(l) + O 2 (g)

However, the decomposition of the hydrogen peroxide into water and oxygen is catalyzed by the iodide ion.

H 2 O 2 (aq) + I - (aq) → OI - (aq) + H 2 O(l)

H 2 O 2 (aq) + OI - (aq) → I - (aq) + H 2 O(l) + O 2 (g)

The dishwashing detergent captures the oxygen as bubbles. Food coloring can color the foam. The heat from this exothermic reaction is such that the foam may steam. If the demonstration is performed using a plastic bottle, you can expect a slight distortion of the bottle due to the heat.

Elephant Toothpaste Experiment Fast Facts

• Materials: 30% hydrogen peroxide, concentrated potassium iodide solution or a packet of dry yeast, liquid dishwashing detergent, food coloring (optional), starch (optional)
• Concepts Illustrated: This demonstration illustrates exothermic reactions, chemical changes, catalysis, and decomposition reactions. Usually, the demo is performed less to discuss the chemistry and more to raise interest in chemistry. It is one of the easiest and most dramatic chemistry demonstrations available.
• Time Required: The reaction is instantaneous. Set-up can be completed in under half an hour.
• Level: The demonstration is suitable for all age groups, particularly to raise interest in science and chemical reactions. Because the hydrogen peroxide is a strong oxidizer and because heat is generated by the reaction, the demonstration is best performed by an experienced science teacher. It should not be performed by unsupervised children.
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Elephant Toothpaste Science Experiment

• Written by Children's Museum Team
• Posted on Friday May 1, 2020

Where Do Elephants Pack Their Toothpaste? In Their Trunk!

This demonstration’s called Elephant’s Toothpaste because the chemical reaction produces a large foamy mess that looks like toothpaste squirting out of a tube. It is so big that only an elephant could use toothpaste this large. It is, of course, not toothpaste so please do not try to brush your teeth with it ! The kids-safe version below is harmless but certainly wouldn’t taste very good.

Vocabulary:

• Baking soda
• Endothermic

Elephant Toothpaste Materials:

 Hydrogen peroxide – 6% if possible. 3% (what is sold in drug stores) will give off a smaller reaction  Yeast  Dish Soap  Liquid watercolor or food coloring (optional)  Medium-sized soda-pop bottle (empty)  Funnel  Tiny scoops & spoons (about ¼-ish teaspoon) + a Tablespoon measure  Pipettes  Tub of water/sink close-by  Safety gloves  Safety glasses

Elephant Toothpaste Directions

• Before you do anything, put the soda-pop bottle on a baking tray or large bowl.
• Mix 1 Tbsp yeast into 3 Tbsp of warm water in a small paper cup. Consistency should be that of melted ice cream. Set aside to get all bubbly and happy (as yeast and warm water always do)
• Using the funnel, carefully pour about ½ cup of the Hydrogen Peroxide into the soda bottle
• Add some liquid watercolor (optional)
• Add about 1 Tbsp of dish soap to the Hydrogen Peroxide
• Use the funnel to pour the yeast mixture into the soda-pop bottle, then step back.

What’s Happening?

When hydrogen peroxide breaks down, it turns into oxygen (O 2 ) and water (H 2 O). Normally this breakdown happens very slowly. But the reaction could be done faster by adding a catalyst. Yeast is an organism that contains a special chemical called catalase that can act as a catalyst to help break down hydrogen peroxide. Catalase is present in almost all living things that are exposed to oxygen, and it helps them break down naturally occurring hydrogen peroxide.  This means that if you mix yeast with hydrogen peroxide, the hydrogen peroxide will rapidly break down into water and oxygen gas. The oxygen gas forms bubbles. These bubbles would usually escape from the liquid and pop quickly. But, adding a little dish soap provides additional surface tension, allowing the bubbles to get trapped and creating lots of foam. This foam looks like a giant squeeze of toothpaste—almost big enough for an elephant! Because this reaction is exothermic, the bottle and the foam will be warm.

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How to make elephant toothpaste

This is one to really sink your tusks into.

Dr Stuart Farrimond

Need some eye-opening and fun science experiments to try at home with family and friends? Here's one from our DIY Science special in issue 310 of BBC Focus magazine ( subscribe here ) .No specialist equipment is needed for this one, butjust remember to wash your hands after making elephant toothpasteand make sure that children are supervised by an adult.

To make elephant toothpaste you will need:

• Safety goggles (best to get a pair that completely seal your eyes so that notoothpaste gets underneath)
• Washing-up liquid
• Dried yeast (make sure that it is in date)
• Food colouring
• Empty 500ml plastic drinks bottle
• 9% hydrogen peroxide, whichis a mild skin disinfectant that you can buy over the counter at pharmacies(Warning: hydrogen peroxide can irritate eyes and sensitive skin, so wear safety glasses and gloves. Do not swallow hydrogen peroxide or splash in eyes.)
• Glycerine, which you can find in the baking section of the supermarket, or in bigger bottles at a pharmacy
• This experiment is messy! Either work at a table that’s easy to clean, or head outside.

• Put on gloves and safety glasses.
• Pour half a cupful of hydrogen peroxide into the bottle (more if you’re using a larger bottle).

• Pour in up to two tablespoons of glycerine.
• You are going to be making toothpaste, so why not add some food colouring? I drizzled some orange food colouring down one side of the bottle and blue down the other.
• Pour the (now activated) yeast into the bottle using the funnel.
• Stand back as the bottle erupts with a thick foam that seems to just keep on going. It looks like toothpaste, but it’s definitely not for brushing teeth with!

What's going on?

Elephant toothpaste isn’t toothpaste at all, but a foam of oxygen bubbles that have been ensnared by the washing-up liquid and thickened by the glycerine.

Chemically, hydrogen peroxide is made of two hydrogen atoms and two oxygen atoms (H 2 O 2 ). This makes it similar to water (H 2 O) but with an extra oxygen atom (O) – yet hydrogen peroxide is poisonous to living things, which is why we use it as a disinfectant, and why we keep it away from our mouths and eyes.

Yeast, however, carries a protective enzyme called catalase that destroys hydrogen peroxide. The moment the living yeast cells touch the liquid disinfectant, the enzymes go to work tearing the hydrogen peroxide molecules apart, into water and oxygen. The oxygen bubbles up vigorously to form a rapidly growing foam that erupts from the top of the bottle, such is the fervour of the reaction.

You can try this science demonstration with liver instead of yeast, as this organ also contains enzymes that destroy hydrogen peroxide.

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