This simple experiment uses common household items to demonstrate a chemical reaction, resulting in the inflation of a balloon without using lung power. It is an engaging way to visualize the power of gas expansion and pressure generated from a mixture of a solid and a liquid. This activity showcases basic chemistry principles that convert reactants into a gaseous product, making the invisible process observable. The entire setup is easy to assemble and provides a rapid, satisfying result.
Gathering Supplies and Safety Checks
You will need a clean, empty plastic bottle, a balloon, baking soda (sodium bicarbonate), white vinegar (acetic acid), a small funnel, and a measuring spoon. Before starting, ensure that an adult is present for supervision. It is recommended to perform the experiment over a tray or in a sink to contain any potential overflow.
The expanding gas creates pressure, so securing the balloon tightly to the bottle opening is important to prevent it from popping off. Consider wearing protective eyewear, like safety goggles, to shield against accidental splashes of vinegar. Pre-stretching the balloon can help it inflate more easily during the experiment.
Executing the Experiment Step-by-Step
Begin by pouring approximately one cup of white vinegar into the plastic bottle, filling it about one-quarter of the way. Next, fit the balloon opening over the narrow end of the funnel. Using a measuring spoon, add about two teaspoons of baking soda into the funnel, shaking it gently until all the powder drops down into the balloon.
Once the baking soda is inside the balloon, remove the funnel and carefully stretch the mouth of the balloon over the opening of the bottle. Keep the balloon draped over the side, ensuring the baking soda remains suspended and does not fall into the vinegar prematurely. Check to make sure the balloon forms a tight seal around the bottle’s neck.
When you are ready to start the reaction, lift the balloon straight up so that all the baking soda falls into the vinegar below. The mixture will immediately begin to bubble vigorously as the chemical reaction starts. Keep a firm grip on the balloon’s mouth until the reaction slows down and the balloon is fully inflated, capturing the gas generated inside the bottle.
The Chemical Reaction Explained
The inflation of the balloon is a direct result of an acid-base reaction between the two primary ingredients: acetic acid (the active component in vinegar) and sodium bicarbonate (baking soda). When these two substances meet, they immediately react to produce three new products: sodium acetate, water, and the gaseous compound known as carbon dioxide.
Sodium bicarbonate and acetic acid yield sodium acetate, water, and carbon dioxide. Carbon dioxide is a gas, and unlike the initial solid and liquid reactants, gas particles require a much larger volume of space. As the reaction vigorously produces this gas inside the sealed bottle, the pressure quickly increases.
Because the balloon is the only available exit, the rapidly expanding carbon dioxide gas flows upward and pushes against the flexible material of the balloon. This outward push of the gas particles forces the balloon to inflate. The inflation stops when one of the original reactants is completely consumed, halting the production of new carbon dioxide gas.