The challenge
Will an egg float when the water changes?
What you need
- Two transparent glasses
- Two fresh uncooked eggs
- Water
- Table salt
- Spoon
Safety first
Adult supervision is required. Handle raw eggs hygienically, wash hands and surfaces, and do not eat experiment eggs.
Before you begin
What do you predict will happen? Write down your idea before trying it.
Step by step
- Fill both glasses with equal amounts of water.
- Stir several spoonfuls of salt into one glass until dissolved.
- Gently lower one egg into each glass.
- Observe where each egg settles; add more dissolved salt if needed.
What did you notice?
Compare your prediction with what happened. What changed between the first and second attempt?
Why it works
Dissolved salt increases water density. When the salty water is dense enough, the upward buoyant force can support the egg.
If it doesn’t work
Check your setup, measurements and materials. Make one change at a time and try again. Results can vary.
Try next
Try different salt concentrations and record the changes.