My daughter had to do a science project for school. She came up with the idea to show something amazing, that water can actually float on water. To make this visible she decided to use food coloring to give each water layer a different color.
There is, however, a little secret to the experiment. The water-layers have to have different densities; or they simply mix.
Give fresh water into the left cup – and salty water into the right cup.
Add orange food coloring to the fresh water and blue food coloring to the salty water
Slowly add fresh water to salty water – AND LATER salty water to fresh water
Left: salty water added to fresh water – the water mixed
Right: fresh water added to salty water – the water layered
Observation & Conclusion
- The orange fresh water layers on the blue salty water.
- The blue salty water does not layer on the orange fresh water.
- Pouring slowly was important.
- Water can layer on water if the layers have different densities.
- Salt makes the density higher.
- Only lower densities (fresh water) float on higher densities (salty water) – not the opposite.
And finally, my daughter’s poster, the way she presented it in school. Mum being very proud of the little scientist to be 😉
Thank to Tamara & Raha International School Abu Dhabi