The premier destination for fun science projects & experiments for kids grades K-8 since 2010!


Test if salt water is more dense than fresh water

Suitable For

Grade 3



Time Required

 <1 Hour



What’s it about?

‘Density’ is a physical property that all matter possess and can be used to compare two substances that have the same ‘volume’, but their ‘mass’ is not the same. Salt water is more ‘dense’ than fresh water, and for the same reason it is easier to float a boat in the sea. Test this scientific fact in the following experiment:

Topics covered

Density, Floating

What will I need?

  • 2x EGGS

Procedure (Method)

Unfortunately, this section is only available in the e-book version of the project.

How does it work?

Unfortunately, this section is only available in the e-book version of the project.

This science experiment works because when the salt is added to one of the glasses with water, the solution’s density is increased. The egg will float in the salt water solution because it has a lower density than salt water. On the other hand, the egg will sink in the fresh water because it is denser than fresh water.

When the two liquids are carefully added together, they do not mix right away. The egg sinks through the fresh water and come to rest or ‘floats’ on the salt water solution (and seem to be suspended in the middle).

Like the sound of it?

Why not check out the full worksheet in one of our popular e-books?

This particular science project can be found in any of the following Experiland e-books:

Experiland e-books contain detailed steps, including illustrations, to complete the science projects from start to finish.

Science project ebooks for kids

Experiland's science e-books contain a diverse range of several hundred of exciting science projects, ideas and experiments.

A project introduction and background, complete listing of required materials, step-by-step instructions on how to carry out the project, why it works, learn more section, as well as a science glossary with all the relevant terms make up each of the all-inclusive science project worksheets in our e-books!

Get your e-Book!