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Why Salt & Soda Make Bubbles When Together

The chemistry behind even the most simplistic of experiments can baffle most, such as the bubbling as a result of salt being added to soda. Soda itself is already "bubbly" due to its carbonation, but add a dash of salt and it bubbles even more violently than on its own. This bubbling effect has to do with the salt's alkaline nature and the release of carbon dioxide when it reacts with the soda.

Salt
- Salt is one of the most plentiful minerals on earth, as well as one of the most basic molecules. It is vital for your health in small quantities but harmful in large doses. The primary ingredient in table salt is sodium chloride. Sodium is a natural alkalizing mineral (non-acidic) with a pH of 14. Once wet, the alkaline properties of the salt cause carbon dioxide gas bubbles. Chloride is an essential electrolyte for acid/base balance, nerve impulse transport and fluid regulation. Sodium chloride is made of one sodium ion and one chlorine ion.
Soda
- Carbonated water is composed of basic H20 with carbon dioxide and is created through a process called carbonation. The carbon dioxide causes the water to become effervescent, meaning it releases gas bubbles that make the water fizzle. Soda is primarily composed of carbonated water, which is why there is a "hiss" sound when you open a can or bottle.
Salt and Soda
- Dropping salt in soda causes the salt to dissolve and subsequently reduce the availability of the soda's solvent to dissolve the carbon dioxide, which is due to the increase in solutes causing a change in the balance of the soda's chemistry, also causing the soda to release some of its carbon dioxide. The salt falling into the soda allows for the formation of nucleation sites for carbon dioxide bubbles. These bubbles transition to the surface and cause the bubbling effect you notice after pouring salt into soda. The salt dissolving into the soda causes a change in the pH balance of the solution. In return, the pH shift causes a decrease in the solubility of the carbon dioxide, thus releasing CO2 gas, or the bubbles you see when salt is combined with soda.
Other Uses of Salt and Soda
- Salt and soda can be used as household cleaners by applying a dab of club soda and a small amount of salt on a small cloth. Use the cloth to wipe down the refrigerator for a refreshing effect. Salt can also be used for a variety of other applications, such as cleaning oven spills, coffeepots, maintaining sink drains and getting rid of rust.

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