Embedded Files
In this simple experiment, students can easily visualize the concept of density, by comparing what happens when an egg is dropped into a cup of freshwater compared with a cup of saltwater. Sink or float?!
Grade Level: 2 - 8
Time: 15 - 30 minutes
Learning Standards: PS1.A, PS1.B, MP.4, SL1
Here's what to do
Here's what to do
Fill one cup 2/3 full with water
Fill one cup 2/3 full with warm water, and mix in 3 tbsp of salt; stir well until dissolved
Start with freshwater - have students predict what will happen when the egg is placed in the cup
Place the egg into the freshwater and see what happens! Discuss their thoughts about why!
Next do the same steps with the egg in the saltwater cup (predicting, experimenting, wondering, and discussing!)
Follow up by more deeply exploring the difference in density between fresh water & saltwater
Materials needed
Materials needed
Two clear cups - glass or plastic (large enough for egg)
Salt (course sea salt may have better results)
Warm water
Egg (make sure eggs are fresh)
What are we learning?
What are we learning?
Saltwater is water containing a measurable percentage of dissolved minerals and salts (in the water cycle, it is found in the oceans, seas, saltwater lakes, bays & estuaries, and sometimes even groundwater!). This measure is known as "salinity," and as salinity increases, so does the density and mass of the water. Due to the increased density of saltwater, an egg will float, whereas it will sink in the less dense freshwater.
What to expect
What to expect
The egg will sink in the freshwater & float in the saltwater.
Page updated
Google Sites
Report abuse