Spoon Or Other Measuring Device

Potential Volcano

Materials:

· Balloons

· Funnel

· spoon or other measuring device

· baking soda

· vinegar

· Lemon juice

· Juice or soda bottle

Experiment:

1. Add two large spoonfuls of baking soda in a balloon using the funnel.

2. Half fill the bottle with vinegar.

3. Stretch balloon over neck of bottle, without allowing baking soda to fall into vinegar.

4. Hold balloon upright, allowing baking soda to fall into vinegar.

Related Terms:

Heat of vaporization: energy required to be input (or removed from the system, depending on convention), to convert a liquid to a vapor or gas

Diffusion: translational motion of molecules in liquid or vapor states

Chemical Reaction: chemical change of your starting materials, or create a new chemical species or product.

Physical Reaction: physical change, materials remain the same chemically on a molecular level.

Acid/Base

Sodium bicarbonate (baking soda): NaHCO3(s)

2 NaHCO3(s) à Na2CO3(s) + CO2(g) + H2O(g)

Heating or baking sodium bicarbonate causes it to form a solid, and two gases, carbon dioxide and water. A similar reaction can occur by mixing with an acid. Baking soda itself is a base.

Carbonic acid decomposes to form CO2 and H2O.

The carboxyl group in acetic acid gives off (releases) its H ion (the H single-bonded to the O in the O-H group single bonded to the C==O), which attacks the baking soda, and cleaves off the carbonate group (HCO3-) and bonds to form carbonic acid. As the carbonic acid decomposes, carbon dioxide and water are released to inflate the balloon.

The double bond in the carboxyl group draws (or tries to pull) electrons from the C-O-H bond in the carboxyl group. As a result, the O-H bond is placed under stress, and is weakened, which allows the H ion to cleave off more easily, and be able to react with the baking soda. Therefore, O-H groups that are part of a carboxyl group will more easily give up the H ion than an O-H group attached to a simple C molecule, such as in citric acid.

Kinetics: the more hydrogen ion available to cleave the baking soda, the faster the CO2 and H2O are produced, and the faster the balloon inflates.

Baking soda is a base.

Baking powder is baking soda, plus an acid, and corn starch. When water is added, the solid is dissolved, the base and acid mix and generate CO2 and H2O.

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