How can we create a rainbow in a cup using a sugary solution?
"It can't be done!" the doubters cried.
BUT WAIT... Hmmmm... LET ME THINK...
The children's brains fizzed. Cogs whirred. Ears smoked. And then from a quiet corner of the room a little voice said,
"Some liquids are heavier than others!"
YIPPEE! Suddenly scientific thoughts began to swirl and eventually we designed our little experiment.
The made sugar solutions of different saturations which resulted in solutions with different densities. The more dense the solution, the lower the layer in the cup. The less dense the solution, the higher the layer in the cup. Our purple layer was saturated (no more solute could be dissolved in the solvent) and so was the most dense.
We had to measure carefully and add each solution gently to avoid overly agitating the solutions which could cause them to mix together.
Our results are simply beautiful. Science is brill! And pretty!!