Kids will love this rainbow variation on the classic naked eggs experiment. Don’t just try the rubber egg experiment without color, make rainbow rubber eggs instead!
My kids like colorful, dramatic science experiments for kids. There is nothing tame or boring about making rainbow rubber eggs!
This experiment has both the “wow” factor and the gross factor that will make confirmed science lovers for life.
We used this experiment as a fun addition to our St. Patrick’s Day STEM activities, but you can also use it for an Easter STEM activity or any time of year as a crowd-pleasing STEM activity.
You can also try the rainbow version of this experiment for any egg in vinegar science fair project.
How to Make a Rubber Egg
In just a few hours, you can completely transform eggs and remove the shell.
For more fun Easter STEM Activities, try exploding rainbow eggs, salt crystal Easter eggs, Peeps slime, or make an Easter lava lamp!
What is a Rainbow Rubber Egg?
Did you know that inside of every egg shell is a membrane holding the “guts” of the egg in place?
This membrane is located between the egg shell and the egg white. There are actually two layers of membrane inside every egg (called inner and outer membrane, not to be too on the nose).
The membranes protect the growing chick from exposure to bacteria, but the membranes are semi-permeable, which is how the dye used in this experiment colors the eggs and why they get bigger when placed in water or vinegar.
The egg membrane is strong, which is how you can play with it and bounce it without breaking it (of course, too much pressure will burst the eggs, causing a huge mess!).
Fun fact: There is also keratin inside an egg membrane, which is present in human hair.
When the acid in the vinegar eats through the calcium shell, the membrane is left encasing the egg. The texture feels rubbery, hence, the rubber egg.
NAKED EGG EXPERIMENT STEAM QUESTIONS
Transform this rubber egg science experiment into a STEM project by asking a few extra questions and adding variables.
- Will shells dissolve in different materials?
- What happens if you use a different kind of dye?
- Will eggs change color without the help of vinegar?
Experiment with different liquids, like soda, water with baking soda added, milk, coffee, water, and oil.
After removing the eggs from the vinegar, watch what happens when you let them sit out on the counter without any liquid.
- Do they dry out?
- What happens if you put the eggs in a salt solution?
What you’ll need to make the rubber egg experiment:
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Osmosis Egg Experiment Results
The osmosis egg experiment teaches children how liquid moves through a membrane. The addition of dye to the rubber egg experiment can show how osmosis works.
For the main rainbow naked egg experiment, however, the scientific concept is a chemical reaction and a lesson in dissolving.
The vinegar eats through the calcium shell, but cannot dissolve the egg’s membrane, which is how the eggs retain their rubbery appearance after the experiment is complete.
The egg membrane is semi-permeable, which simply means that the liquid vinegar will pass through the membrane into the egg.
When the vinegar is dyed, the dye and the vinegar seep into the egg white, creating fun rainbow colors! The brighter the dye that you use, the brighter your egg rainbow will be!
Rubber Eggs Experiment Directions
Fill each container about 1/2 full of vinegar. Add about 10 drops of food coloring to each jar.
Carefully place a raw egg inside each jar. Let the eggs sit for about 48-72 hours in the vinegar.
Try putting other eggs in different liquids to see if they produce a different or similar reaction.
Over time, the vinegar will break down the calcium on the egg’s shell, leaving the egg completely whole, but soft.
When the surface of the water has a weird scummy film, the eggs are ready to come out.
Remove the eggs from the jars (carefully) and rinse them in water.
They are completely colored!
Gently roll and bounce the eggs and watch what happens!
When the kids are done admiring the eggs, break them open. The kids might be surprised to see that the egg yolk is still yellow!
The high protein content of the yolk prevents the egg’s cells from absorbing the colored liquid that is absorbed by the rest of the egg.
Get even more Easter STEM ideas here!