A small experiment in scientific inquiry – homemade rainbow cups

Rainbow Cup


Experimental materials

Water cup, cooking oil, detergent, coloring, alcohol, stir bar, water.




Step 1

Pour some detergent into the glass, drizzle a few drops of green food coloring, stir, and make a green detergent on the bottom of the cup.


Step two

Prepare a small half cup of red solution and slowly pour over the green detergent along the tamper.


Step 3

Take a small half cup of yellow cooking oil and slowly pour it over the red solution along the glass.


Step 4

Prepare a small half cup of blue alcohol solution, then slowly pour over the yellow cooking oil along the stir bar.


Step 5

The four-color liquid did not mix together, a beautiful rainbow cup was made!


Experimental principle

The greater the density, the greater the gravity of the object, so the dense liquid sinks, the small density liquid floats, the density of detergent > the density of water> the density of edible oil> alcohol density, so finally the cup is divided into four layers and becomes a rainbow cup.