Density Rainbow

Sugar water is denser than water--the more sugar, the denser. This experiment shows you how to layer different densities into a rainbow of color.

Pouring a Skittles Density Rainbow. (The entire process took about four minutes.)

What you need:

• Five small cups for mixing
  
• A clear glass
  
• A wide spoon
  
• Skittles
  
• 2 red
  
• 4 orange
  
• 6 yellow
  
• 8 green
  
• 10 purple
  

To do:

1. Fill five cups with 2 Tbsp of water each.
   
2. Dissolve the Skittles, each color in a separate cup. If the candy is not dissolving, stir frequently or heat the water. (The waxy film floating on the surface can be removed or ignored; it won't affect the experiment.)
   
3. Pour the purple water into the clear glass.
   
4. Hold the spoon upside-down over the purple water, with the tip of the spoon touching the edge of the bowl above the waterline. Slowly pour the green water down the back of the spoon, so that the green water does not mix in with the purple. Instead, it should float on top.
   
   Alternative method: use a small syringe to make the layers. Suction up the green water, hold the tip of the syringe against the edge of the glass, and gently squeeze the water out to make the layer.)
   
5. Repeat with the other colors, and admire your rainbow.
   

What’s happening:
Since the water with less candy is less dense, it floats on top of the denser layer like oil on water. Unlike oil and water, your sugar water layers will eventually mix together, muddying the color. So admire it while it lasts!