Have students wear goggles and follow safety precautions when using BTB solution. Bubble Solution Bubbles can be used to investigate a variety of phenomena, including motion, surface tension, and refraction of light. Stir this mixture carefully so that an excessive amount of suds does not form. Have the students wear safety goggles when blowing soap bubbles. The growth of crystals can be observed by making a crystal garden.
Half fill a clear plastic jar with hot water.
Slowly add salt to the water and stir to dissolve. Continue adding salt until no more will dissolve. Place 1 tablespoon of vinegar in the water. Place a piece of charcoal or small porous stone in the jar. Beautiful crystals will soon start to form on the charcoal or stone.