Egg and Toothpaste Experiment (Learn Importance of Brushing Your Teeth)

This wonderful experiment using eggs and toothpaste helps parents and teachers to teach children how important is brushing teeth.

Science Behind The Egg and Toothpaste Activity

Most parents out there have had difficult times to make your child’s brushing time fun and excited!!

Also, many parents experienced annoying times to stop their kid from grabbing artificial sweeteners like soda, candies, etc.

If you are one among such parents whose warnings just remain as warnings which are not put into serious action by your child, here is the super-fun activity for you!

Egg and Toothpaste Science Activity

Objective: To observe how eggshell is protected by tooth paste and learn how tooth reacts to acids and stain.

Time: The activity requires 24 hours to show stain on eggs.

Inspiration: One day, my younger daughter (who is 5 years old) came up with a question “Mumma! How come our teeth becomes stained and turn into yellow colored?”

Immediately, I asked her what is wrong with her teeth.

She replied, “Mumma! I am completely fine but today in my school, one of my close friends was suffering from teeth pain and I observed her teeth were yellow tinted.”

Then, I understood the complete picture and turned her question as a great opportunity to show her how important is brushing our teeth using toothpaste.

For this activity I used eggs and toothpaste to show her importance of brushing.

Why eggs? Eggshells are having the same material as of our tooth and bone composition. So, eggs make a great ingredient in this activity.

Appropriate For Age Group: this fun science investigation is perfect for preschoolers, kindergarten, and elementary children. Toddlers can enjoy and try to understand the results but they may not exactly know the science involved in this experiment.

Materials Required: For your surprise, this super cool egg and tooth paste science activity requires 3-4 ingredients from the fridge of your kitchen. Do you want to know what those simple supplies are!? Have a look here:

Material Required For Egg And Toothpaste Experiment

1) 4 plain and raw eggs

2) Tooth Paste (any kind of toothpaste right in your home is fine)

3) Coca Cola

4) Black Coffee

That’s it! Just collect these items from your kitchen and get ready at the experiment table to investigate eggs and toothpaste hands-on.

Simple Step-by-Step Instructions

This fun science investigation takes a few minutes to finish but we need to wait for a day or 24 hours to see the spectacular results. So, plan accordingly if you want to perform this activity either at home or in a school event.

Let us jump into the simple instructions and follow the same while experimenting with eggs and toothpaste.

Step-1: Do little Preparations

Pour Black Coffee Into Glass cups

Before you start this activity, you need to help your children in making black coffee.

If your children are too young to manage burners, then prepare black coffee and directly offer them to use in the activity.

And keep four neatly cleaned transparent glasses ready! Also make sure the eggs you picked up are in good condition that means there is no breakage or leakage of egg inside contents.

Because leaking egg can damage the whole experiment results and looks messy too!

Drop Egg Into Black Coffee

Step-2: Keep the eggs ready for the Experiment

Apply Toothpaste On The Egg

Bring the eggs to the room temperature in order to achieve appropriate outcome.

Once you check the eggs are in good condition, ask your child to wash the eggs carefully with neat hands. And then let them dry the wet eggs using paper or cloth napkins.

That’s all! Your eggs are ready to go on to the experiment table.

Step-3: Cover the eggs with Toothpaste  

Cover the eggs with Toothpaste

Ask your child to coat two plain eggs with good amount of toothpaste evenly. And the rest two eggs remain as it is. That means we are not coating these eggs with any other material.

Drop ToothPaste Coated Egg Into Black Coffee

Step-4: Arrange the Glasses for Experiment

Pour Coca Cola Into Glass cups

Now pick four transparent glasses and fill two glasses with coke and the other two glasses with black coffee.

Make sure you are placing these glasses on a plain and flat surface such that you can avoid unnecessary disturbances and messy work during investigation.

Also, remember to fill the glasses with the respective liquids in equal amounts. If you want, you can measure and pour the liquids in to the glasses to keep the quantity equal.

Step-5: Drop the Eggs

Drop Egg Into Coca Cola

It is time to drop the eggs into the liquids for investigation! Pick one plain egg and one toothpaste coated egg and drop them in coke filled glasses respectively.

After that pick another set of eggs i.e. one plain egg and one egg covered with toothpaste and drop into the two glasses filled with black coffee respectively.

Drop ToothPaste Coated Egg Into Coca Cola

Step-6: Allow the set-up for a day

This is so simple and easy step where you have nothing to do or investigate! Yes, ask your children to leave the experiment set-up for 24 hours completely to see the fascinating results.

Step-7: Observe the Results

Are you done waiting for 24 hours to see the outcomes? Here are the results we experienced after a long wait of 24 hours. Hahaha! Yes, waiting for 24 hours is a long wait for children to see the results.

I am attaching the results table and pictures for your reference. Just compare and see whether you also experienced the same.

Glass-1 filled with coke and plain egg got stains where the one coated with toothpaste and dropped in glass 2 with coke does not have any stains.

In the same way, the plain egg dropped in black coffee showed stains whereas the egg coated with tooth paste does not show any stains. You can see the pictures attached for your reference.

Science behind the Egg and Toothpaste Activity

Egg And Tooth Paste Science Activity GoScienceGirls

Egg shell is the rich source of calcium carbonate whereas black coffee and coca-cola are acidic in nature.

When the plain egg dropped in the coke and black coffee, the acidic contents immediately start reacting with calcium carbonate and forms stains.

As this is a slow process we are letting the experiment set up for 24 hours to see best results. On the other hand, the eggs coated with toothpaste, when dropped in the coke and black coffee, the fluoride in toothpaste build a protective layer between the eggshells and acidic solutions.

The fluoride in toothpaste makes the eggshell stronger and protects it from reacting to acidic contents of coke and black coffee.

Fluoride is the natural mineral helps the outer layer of eggs and teeth become stronger naturally.

Science Experiment With Egg And Tooth-Paste

Egg-Toothpaste Science Experiment and Importance of Brushing Teeth

Eggshells denote the teeth of humans as the outer layers of both made of same material i.e. calcium. And the chemical composition of eggs, bones, and teeth are same.

So, we are representing eggshells as teeth. Coke and black coffee represents the acids caused due to bacteria in the form of plaque. Plaque is the result of constant consumption of artificial sweeteners.

So, when we brush our teeth properly using toothpaste, the fluoride content in it helps teeth from the damage of acids, cavities, stains, and plaque.

This is how we can explain and give a great demonstration on importance of proper brushing teeth with fluoride contained toothpaste.


What happens when you put toothpaste on an egg?

The fluoride content in toothpaste keeps the eggshells safe from the acids present in black coffee and coke. Hence, the toothpaste acts as a strong protective layer between the acids in coke and calcium content of eggshell respectively.

What liquids dissolve egg shells?

Liquids rich in acids are the best liquids to dissolve egg shells. For example: Orange Juice, Vinegar, Coke, Black Coffee, and other acidic liquids.

The acids in these liquids react with calcium carbonate in egg shells. Carbon dioxide is the gas released during this reaction.

If you let the reaction to continue for long hours, you can observe acids dissolving the egg shells gradually and completely.

Finally, the reaction leave the egg to uncover its outer layer and exposes inside contents.  

What happens when you put an egg in water for 24 hours?

Osmosis is the process through which sudden drive of solvent particles happen from less concentrated solution to high concentrated solution.

This is the same happens when you place an egg in pure water for 24 hours.

The water travels from outside part of the egg through the semi-permeable membrane to the inside part of the egg.

You can observe osmosis when the egg swells up after sometime the egg put in the water.

Otherwise, add some food color to the water and let the egg sit for a day.

You can easily observe the transmission of water through the color travel from outside to inside part of egg.  

What happens if you put an egg in Coca Cola?

Take a glass of coca cola and place an egg in it. Let it remain in the coke solution for 24 hours. Then, take out the egg and you can see the egg is stained. This is because the acid the coke reacts with calcium in the egg shell.

Does Coke dissolve egg shell?

Absolutely yes! Coke contains dissolving agent in it i.e. acidic nature, which is why the egg shells dissolves completely when an egg is placed in coke solution and left for long hours.

The egg shell is nothing but calcium carbonate which softens and melts on long exposure to acidic solutions like coke.

You can observe this amazing chemical reaction by witnessing the carbon dioxide gas releasing as a result of reaction in the form of tiny bubbles.


Leave a Reply

Your email address will not be published. Required fields are marked *