Fireworks In A Glass

Fireworks are a beautiful and fun part of many celebrations, but not something you want kids to make themselves. However, even very young explorers can experiment with these safe underwater 'fireworks'. I have to admit, when my oldest daughter (who loves science experiments) wanted to try this one, I wasn't too sure - but even my hubby and I thought this was pretty cool!

What You Need

water

oil

food coloring

tall clear glass

another cup or glass

  Create Fireworks in a Glass

1. Fill the tall glass almost to the top with room-temperature water - (about 1" from the top).
2. Pour a little oil into the other glass. (1-2 tablespoons)
3. Add a couple of drops of food coloring. We used one drop each of Blue, Green, Yellow and Red, but you can use any colors.
4. Briefly stir the oil and food coloring mixture with a fork. You want to break up the food coloring drops into smaller drops, but not thoroughly mix the liquid.
5. Pour the oil and coloring mixture into the tall glass.
6. Now watch! (at first, ours didn't do anything right away - but keep watching) The food coloring will slowly sink in the glass, with each droplet expanding outward as it falls, resembling fireworks falling into water.

        

How It Works

Food coloring dissolves in water, but not in oil. When you stir the food coloring in the oil, you are breaking up the coloring droplets (though drops that come into contact with each other will merge... blue + red = purple). Oil is less dense than water, so the oil will float at the top of the glass. As the colored drops sink to the bottom of the oil, they mix with the water. The color diffuses outward as the heavier colored drop falls to the bottom.