Bath bombs release colorful fizz and fragrance when dropped into water. The technique is simple-just mix the ingredients in the right proportions, press the mixture into the mold, and let it dry for 24 hours. Choose from 5 trendy molds and mix the three primary-color baking sodas to make a whole rainbow of colors. Includes information on the chemistry behind the fizzy reaction. Contains: Baking soda in 3 colorsCitric acid5