PURPOSE: To show that pure water is not conducting, but a solution of an electrolyte is conducting.
DESCRIPTION: A 110 VAC lead is connected to a series arrangement of a light bulb and two parallel plates. Shorting the plates will light the bulb. Inserting the plates into distilled water does not light the bulb. Inserting the plates into tap water lights the bulb dimly and inserting the plates into salt water lights the bulb fully. An electrolyte solution allows passage of electric current.
REFERENCES: (PIRA 5D30.10)
EQUIPMENT: Bottles of distilled water, tap water, and salt water, series 110 VAC circuit with light bulb and two plates.
SETUP TIME: None.
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