When we have the balloon well fastened to the bottle, we drop its content inside the bottle. At this moment a chemical reaction begins to take place between the vinegar and the sodium bicarbonate… and as if by magic the balloon is inflated.
Thus, when vinegar and specifically the acid it contains, which is acetic acid (CH3COOH), and a base, which is sodium bicarbonate (NaHCO3), are mixed, carbon dioxide (CO2) is produced, among other products. This gas is released in the form of bubbles and has a tendency to escape from the bottle and reaches the balloon causing it to swell.
When the bubbles are no longer produced, the chemical reaction is finished and the balloon will no longer inflate. Chemical reactions are finished when the reactants, or at least one of them, are consumed. The chemical reaction in our experiment is as follows:
What is baking soda and vinegar for?
Queralt invites you to discover what happens when we mix baking soda and vinegar, a base with an acid. We will see the process by which some substances (the reactants) are transformed into other different substances called products. This is an acid-base chemical reaction that we will understand by simulating a volcano eruption and inflating a balloon without blowing it up.
Eruption of a volcano: With a spoon we put baking soda to cover the base of the glass. We put a thin layer of paprika that will serve as coloring. We pour vinegar on top and we will see how it reacts in such a way that the mixture rises in the glass like a volcano eruption.
When we mix the vinegar (which is an acid) with the sodium bicarbonate (which is a base), they react and transform into water, sodium acetate (a salt) and carbon dioxide (a gas). Carbon dioxide (CO2) is the gas responsible for the volcano eruption bubbles forming and the balloon swelling. When bubbles stop being produced, the chemical reaction is over and the balloon will no longer inflate. Chemical reactions end when the reactants are consumed.
Vinegar with baking soda
Vinegar is used as a condiment or preservative and has existed since time immemorial, although it only began to be produced deliberately in the Middle Ages, when the first artisans appeared who produced it for commercial purposes. At that time, people used the raw materials they had at hand and produced different types of vinegar. One of the properties of vinegar is that it enhances flavor, because it has chemical reactions with some food components.
Acetic acid, being an acid, reacts with basic substances such as sodium bicarbonate, forming other substances. One of them is carbon dioxide (CO2) in the form of gas. This explains the bubbles when vinegar is reacted with sodium bicarbonate. However, the acetic acid contained in vinegar sometimes reacts with some substances and sometimes not with others. This is the same for all substances. Chemists are interested in how a chemical reaction occurs and why substances react.
Baking Soda and Vinegar Experiment Conclusion
One of the most striking experiments in recreational physics consists of creating a partial vacuum inside a container so that it is crushed by the action of atmospheric pressure. The simplest way to create this vacuum is to replace the air with water vapor and then cause it to condense, resulting in a sharp reduction of the internal pressure. Figure 1 shows the sequence of operations required to achieve this effect with a soft drink can (Shakhashiri 1985).
Another effective method to reduce the internal pressure of a vessel, which is partially occupied by a gas, is to remove that gas by a chemical reaction. The problem is that most of these reactions involve gases that require the use of conventional laboratory equipment to obtain or handle (as is the case with sulfur dioxide, chlorine, ammonia, etc.) and do not always result in such a large and rapid reduction in pressure as in the previous method.