Floating eggs
In this activity, students investigate water density by floating eggs in freshwater and saltwater.
By the end of this activity, students should be able to:
discuss the concept of density
discuss how salt increases the density of water
explain why an egg sinks in freshwater but floats when salt is added.
Equipment for experiment
The equipment required for the floating egg activity includes: ice cream containers, eggs and salt.
Download the Word file for:
introduction/background notes
what you need
what to do
extension idea.
Related content
Explore the big ideas that underpin floating and sinking in the article Building Science Concepts: Floating and sinking.
Read the articles Ocean salinity and Ocean density to learn about the vital role salinity and density play in ocean currents and heat circulation.
Activity ideas
Temperature, salinity and water density – use this activity to help your students visualise differences in water density.
Buoyancy in water – students make a Cartesian diver to demonstrate the relationship between volume, mass and density.
Investigating seawater – students investigate some of the properties of seawater.
