what goes with bath bombs

A hot bath sounds especially appealing when the weather outside is terrible. Adding bath bombs to the water can enhance the experience. But what exactly is in these scented spheres, and what makes them so bubbly?

Bath bombs are typically made from three main ingredients: baking soda, citric acid and cornstarch, says Frankie Wood Black, a chemistry instructor at Northern Oklahoma College and an experienced bath bomb maker. Often, bath bombs also contain dyes and perfumes, and sometimes laxative salts.

The fizziness of body wash comes from the chemical reaction that occurs when baking soda and citric acid come in contact with water. Baking soda, or sodium bicarbonate, has the chemical formula NaHCO3. In water, baking soda quickly dissolves and the positively charged sodium (Na+) separates from the negatively charged bicarbonate (HCO3-). [ Goopy Science: How to Make Slime with Glue ]

At the same time, the citric acid dissolves, the individual hydrogen ions (H+) separate from the rest of the molecule, and then the positively charged hydrogen from the citric acid and the negatively charged bicarbonate from the baking soda mix in a very rapid series of reactions. One of the end products is carbon dioxide (CO2). Because CO2 is a gas, it forms small bubbles in the bath water, creating a pleasant fizzing sound.

If there are perfumes or fragrance oils in the shower gel, they will be released into the air with the CO2 bubbles. The sodium in the baking soda and the rest of the citric acid molecules (minus the hydrogen lost when dissolved) remain only in the water.

The cornstarch in the body wash has only one function: to slow down the reaction.

By combining with baking soda and citric acid, corn starch slows down the dissolution of both. The result is dizziness that can last 3 or 4 minutes, rather than just a few seconds.

She mixes 1 cup of baking soda, ½ cup of citric acid and ½ cup of cornstarch in a bowl. All three are available at the grocery store, and Wood-Black notes that citric acid, which is found in soda and candy, can also be used to make cheese. All three can be bought at the grocery store. Citric acid is found in soda and candy, and can also be used to make cheese. After mixing the three ingredients, she adds about 1 teaspoon of water, which is enough to slightly moisten the ingredient mixture and make the powder stick together. She then scoops the mixture into a mold (such as a Santa Claus or star candy mold) to form a shape, and lets the shape dry overnight.

But you can also mix the three key ingredients together and skip the water. Put the mixture in a jar and spoon it into the tub, she says.