Description: A colorless liquid is added to a yellow liquid. The mixture turns pink and foams. Alternatively, acid and powdered carbonate are mixed in a corked test tube and pressure resulting from the gas generated pushes the cork out of the test tube.

Concept: When acids and carbonates react carbon dioxide gas is generated.

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Description: Carbon dioxide gas from a cylinder is bubbled through limewater and calcium carbonate solid is formed causing the limewater to become cloudy. Catch carbon dioxide gas in a jar from a burning bunsen burner. Pour in fresh limewater and it will become cloudy indicating that there was in fact CO2 in that jar.

Concept: Methane when burned reacting with oxygen produces carbon dioxide gas (1).

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Description: A number of different types of chemical reactions are demonstrated.

Concept: Observations of what happens when two chemicals are mixed together can clue us to if and how the chemicals react.

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Description: ice is put in a bowl of water and Universal Indicator and allowed to ?melt?. The color of the indicator changes from green (neutral) to orange (slightly acidic). Drops of NaOH are added until the color of the indicator is green or blue (basic pH). Alternatively, dry ice can be added to water that contains a few drops of NaOH and the color will change from blue (basic) back to orange (slightly acidic).

Concept: Dry ice is solid CO2 and when it is put in water, the CO2 combines with the water to form carbonic acid (H2CO3).

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Description: A copper wire coil in a Christmas tree shape is allowed to sit in a solution of silver nitrate. Within an hour silver metal needles form on the wire.

Concept: Copper metal is oxidized by the Ag1+ to Cu2+ and the Ag1+ ions are reduced by the copper metal to silver metal.

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Description: A light bulb will glow when a substance that conducts electricity is inserted in a break in the wires that leads to and from the power source.

Concept: Solutions that contain ionic compounds conduct electricity. The more a compound separates into its ionic units, the more ions there are in solution. The more ions there are, the more electricity that flows through the solution. For example, the acetic acid will light the bulb dimly and the hydrochloric acid will light the bulb more brightly due to its higher Ka value.

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Description: A light dims as Barium Hydroxide is added to Sulfuric Acid. Once the endpoint of this reaction is reached, the light goes out, and shortly after, the phenolphthalein indicator added turns pink.

Concept: Solutions that contain ionic compounds conduct electricity. When Barium Hydroxide is added to Sulfuric Acid, insoluble Barium Sulfate and water are produced.

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Description: A small amount of water is squirted into an inverted round-bottomed flask full of ammonia gas. This flask is connected by a glass tube to a beaker of water positioned below the flask. As the gas dissolves in the water, water from the beaker is pulled up through the glass tube creating a fountain effect. Phenolphthalein is added to the water in the beaker so that as the water enters the round-bottomed flask it turns pink from the ammonia.

Concept: Ammonia gas is very water-soluble. Ammonia is a base.

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Description: Tollen's Reagent is added to two flasks. A dextrose water solution is added to one and swirled. The contents of the flask turn brown and then silver is plated onto the inside of the flask. Sucrose is added to the other flask. The contents may turn brown but no silver is plated.

Concept: Silver (I) is reduced to silver metal by aldehydes but not by ketones.

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Description: Two colorless solutions are mixed. After 10 seconds, the colorless mixture suddenly turns blue.

Concept: Demonstrates a typical clock reaction; shows the effect of the interaction between chemical reactions that have different rates.

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Description: The pH of some common household acids and bases are measured and compared.

Concept: pH can be used as a measurement of acidity and basicity.

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Description: Red cabbage juice will change to a variety of colors when added to solutions of various pH.

Concept: Red cabbage juice is a pH indicator.

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Description: A sodium hydroxide solution is added to a PET soda bottle that is filled with CO2. The bottle is quickly capped and shaken. The bottle collapses.

Concept: Carbon dioxide reacts with sodium hydroxide. As CO2 gas is removed from the closed bottle, the pressure inside the bottle decreases. The atmospheric pressure on the outside remains the same and will collapse the bottle.

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Description: A Gummi Bear is dropped into a test tube of heated potassium chlorate. The Gummi Bear is combusted.

Concept: Exothermic reactions produce a lot of heat. Potassium Chlorate is a strong oxidizing agent; a fire may start when it is mixed with combustible materials.

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Description: A small chunk of phosphorus is ignited by flame and quickly plunged into a flask containing oxygen gas. The resulting reaction produces heat, smoke and a spectacular bright light that last for 5-10 seconds.

Concept: Finely dispersed phosphorus will readily ignite in the presence of oxygen at room temperature and must be stored under water or in a solvent such as carbon disulfide.

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