Can you make an egg float in water? In this simple science experiment, we take just a few minutes to test the laws of density and discover just how easy it is to make make an egg float!

Below you’ll find detailed instructions and our demonstration video as well as the scientific explanation of “why it works.” We’ve also included a more ideas to explore the concept a bit further.

Watch the Floating Egg Science Experiment

Floating Egg Science Experiment

Supplies Needed for the Floating Egg Science Experiment

2 Eggs
2 Tall Drinking Glass
Salt
Water

Floating Egg Science Experiment Instructions

Step 1 – Fill a tall drinking glass about 3/4 full of water.

Step 2 – Place the egg into the glass of watch and watch it sink.

But this is the Floating Egg Experiment, right?

Step 3 – Fill another tall drinking glass about 3/4 full of water.

Step 4 – Add 3 Tablespoons of salt and stir until combined.

Step 5 – Place the egg into the glass and watch it float.

How Does the Floating Egg Science Experiment Work

Why does the egg sink in regular tap water, but float in saltwater? The answer lies in the density of water! Density is a measure of the mass per unit volume of a substance. Simply said, how much “stuff” in a given volume. Water has a density of 1 g/mL (g/cm3). Objects will float in water if their density is less than 1 g/mL. Objects will sink in water if their density is greater than 1 g/mL.

The egg will sink in regular tap water because the density of the egg is greater than the density of water. The egg’s density is only slightly higher than water at 1.03 g/mL, but that is enough to make the egg sink. When you add salt to the water, you are increasing the density of the water by adding more mass (or stuff) in the given volume. You don’t really change the volume of the water by adding salt. By adding enough salt, you increase the density of the water so that it is higher than the density of the egg and the egg will float!

Other Ideas to Try

Try this experiment again, but instead of using an egg use a potato slice or a carrot slice. You will have to play around with the amount of salt you add to the water because all objects have their own unique density. Add salt a tablespoon at a time and mix well until you cannot see any salt in the solution, then add your object to see if it floats or sinks. Remove your object and keep adding salt until you can get your object to float. To make it a true science experiment, create a data table to keep track of how much salt you add to the solution.

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

Floating Egg Science Experiment

Materials

Egg
Salt
Water
Drinking Glass

Instructions

Fill a tall drinking glass about 3/4 full of water
Place the egg into the glass of watch and watch it sink
Fill another tall drinking glass about 3/4 full of water
Add 3 Tablespoons of Salt and stir until combined
Place the egg into the glass and watch it float