How To Make Colorful Soap Bubbles

Were you one of those kids who tried to add food coloring to ordinary bubble solution to make colored bubbles? Food coloring won't give you bright bubbles, and even if it did, they would cause stains. Here's a recipe for pink or blue colored bubbles, based on disappearing ink, so the bubbles won't stain surfaces when they land.

Safety First

• Please don't drink the bubble solution! Unused bubble solution may be stored for later in a sealed container or disposed of by pouring it down the drain.
• These are bubbles intended for 'blowing bubbles', not for bathing.
• Sodium hydroxide is a strong base. Avoid direct contact with this ingredient. If you do get some on your hands, rinse them immediately with water.

Ingredients

• Liquid dishwashing detergent (or another detergent)
• Water or commercial bubble solution
• Sodium hydroxide
• Phenolphthalein
• Thymolphthalein
• Club soda (optional)

Here's How

1. If you are making your own bubble solution, mix the detergent and water.
2. Add the sodium hydroxide and indicator to the bubble solution. You want enough indicator so that the bubbles will be deeply colored. For each liter of bubble solution (4 cups), this is about 1-1/2 to 2 teaspoons of phenolphthalein (red) or thymolphthalein (blue).
3. Add sodium hydroxide until you get the indicator to change from colorless to colored (about half a teaspoon should do the trick). A little more sodium hydroxide will result in a bubble that keeps its color longer. If you add too much, the color of the bubble won't disappear when exposed to air or rubbed, though you can still react it with club soda.
4. You may find it necessary to dissolve the indicator in a small amount of alcohol before mixing it with the bubble solution. You can use pre-made indicator solution, adding the sodium hydroxide to the indicator rather than diluting with water.
5. You've essentially made disappearing ink bubbles. When the bubble lands, you can make the color vanish by either rubbing the spot (reacting the liquid with air) or by adding a little club soda. Fun!
6. If you have disappearing ink, you could mix it with bubble solution to make disappearing ink bubbles.