Have you ever wondered how bath bombs work? What is the science of the color fizzing ball in a person’s bathtub? But why does it fizz? Using commonly found ingredients, bath bombs can be made easily at home. If you look at the ingredients used, most are not involved in the fizzing chemistry at all. Only three ingredients are important: baking soda, citric acid, and water. When in water, the baking soda and acid start reacting together in an acid-base reaction. The citric acid is obviously the acid, and the baking soda is a base. Have you ever wondered how bath bombs work? What is the science of the color fizzing ball in a person’s bathtub? But why does it fizz? Using commonly found ingredients, bath bombs can be made easily at home. If you look at the ingredients used, most are not involved in the fizzing chemistry at all. Only three ingredients are important: baking soda, citric acid, and water. When in water, the baking soda and acid start reacting together in an acid-base reaction. The citric acid is obviously the acid, and the baking soda is a base.