Description: A few students are given a piece of Bazooka bubble gum that has been pre-weighed and asked to chew the gum for about 20 minutes. After 20 minutes the pieces of gum are weighed again.

Concept: The molar mass (molecular weight) of sugar (sucrose) is large, 342.30 g/mol.

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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 pickle is placed into a light socket and a tungsten electrode is put through the top. The lights are turned low and current is sent arcing through the pickle from a variac that had been plugged into a wall outlet. The pickle glows brightly for a few seconds and eventually starts to smoke.

Concept: The pickling process involves soaking a cucumber in a concentrated salt solution (or brine). Water flows out of the cucumber and salt flows into the cucumber, creating a salty, dehydrated cucumber (or pickle). The inside of the pickle is essentially an electrolyte solution, and conducts electricity.

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