Rainbow Science Experiment

Make a rainbow to learn all about density in this awesome science experiment!

You’ll need: 4 glass containers, food coloring in red, yellow, blue and green, water, a tablespoon measuring spoon, sugar and an eye dropper


  1. Line up your glass containers and number them 1-4.
  2. Leave the first container empty. Add 1 tablespoon of sugar to bowl #2. Add 2 tablespoons of sugar to bowl #3. Add 3 tablespoons of sugar to bowl #4.
  3. Now, one tablespoon at a time, add water to bowl #4 and stir until all of the sugar is dissolved. Make sure to track how much water you use and then use the same amount of water in the remaining 3 containers so each bowl has the same volume.
  4. Add 3 drops of food coloring to each bowl so you have one container of each of the four colors.
  5. Next, grab your eye dropper and squeeze the bulb. Start with bowl #1 which has the lowest density. Let just a bit of liquid into the dropper.
  6. Repeat this process with bowls 2,3 and 4 in that order. You should have a layer of each color in the dropper!

Does it look like a rainbow? Each liquid has a different density because of the added sugar, with #1 having the lowest density (pure water), and #4 has the highest density (most sugar). The food coloring should allow you to see the difference in density in the liquids as the colors remain separate.

Sponsored by National Grid.

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