Easy⏱ time30 min$ cost5
Rainbow Density Column
Stack liquids that refuse to mix into a striped tower sorted purely by density.
Start building ↓
Result first
The build
Step 01
Start dense
Pour honey into the bottom of a tall glass.
Step 02
Layer up
Gently add soap, then coloured water, then oil.
Step 03
Top it off
Float alcohol on top last.
Step 04
Drop objects
Add small items — they settle at their own density.
Working Principle
Each liquid has a different density, so the heaviest sinks and the lightest floats, forming stable layers that won't mix on their own.
The science behind it
A closer look
Density (mass per volume) decides stacking order; objects added float at the layer matching their own density.
Take it further
Variables to test
- 1 Predict where a grape vs a cork settles.
- 2 Warm one layer — does density change the order?
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