What Happens When You Mix Baking Soda With Vinegar to Inflate a Balloon?

By Susan Davis
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Balloons, baking soda and vinegar lead to fun-filled, science-related experiments for any age. These materials are common in science classes from elementary to college. The chemical reaction caused by mixing baking soda and vinegar can cause balloons to race, homemade volcanoes to erupt and bubbles galore. Balloons are often used in baking soda and vinegar experiments because you can see the result of the chemical reaction.

The Chemical Reaction

Baking soda has the chemical name sodium bicarbonate. Vinegar is a combination of water and 5 percent acetic acid. Since both materials contain chemicals, when the two combine there is a chemical reaction. When vinegar and baking soda are mixed, a new chemical called carbonic acid is made. This carbonic acid immediately decomposes into carbon dioxide gas. When you mix the vinegar and baking soda, it's the carbon dioxide gas that makes the bubbles.

Inflating a Balloon

Put 1 teaspoon of baking soda in a medium-sized balloon. Empty a 1-liter water bottle and put 4 tablespoons of vinegar into the empty bottle. Place the balloon over the mouth of the water bottle. Turn the water bottle so that the vinegar pours into the balloon. Turn the bottle right side up and watch the balloon inflate. The balloon inflates because the carbon dioxide gas that is formed fills up the balloon. Try varying the amounts of baking soda and vinegar you use and see what happens.

Interesting Information

The chemical reaction that occurs to make the balloon inflate also happens when baking soda is used in cake and bread mixes that don't contain yeast. There is a chemical reaction when the baking soda combines with the heat of the oven, making the cake or bread rise. Nahcolite is naturally forming sodium bicarbonate. It is found 2,000 feet under ground. Most baking soda that is bought from the store is artificially made.

Other Things to Try

Try putting baking soda in a plastic cup, then pour in some vinegar. The cup will soon overflow with foam and bubbles. Make a volcano by wrapping a cone-shaped object with brown paper. Put red food coloring in baking soda and put baking soda into the volcano through the top of the cone. When you are ready for the volcano to erupt, pour in some vinegar. The bubbles and foam will soon be flowing down the side of the volcano. You can also try filling a film canister with baking soda. Add 2 teaspoons of vinegar on top of the baking soda and quickly close the lid. Turn the canister upside down and set it on a flat surface outside. The carbon dioxide that forms in the canister has nowhere to go, causing the entire container to lift off the ground. Be sure to stand back.