Bath bombs release a chemical reaction when they are placed in water. The main ingredient in bath bombs is sodium bicarbonate (baking soda), which reacts with an acid to produce carbon dioxide gas. The acid used in bath bombs is usually citric acid, which reacts with the baking soda to produce the fizzing effect.
Density is a measure of the mass of a substance per unit volume. It is calculated by dividing the mass of the substance by its volume. For example, if you have a block of aluminum that has a mass of 40 grams and a volume of 10 cubic centimeters, the density of the aluminum block would be calculated as follows:
Density = mass / volume
= 40 grams / 10 cubic cm
= 4 g/cm^3
The unit for density is typically expressed in grams per cubic centimeter (g/cm^3) for solids and grams per milliliter (g/mL) for liquids.