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Colorful Electrolysis - Chemical Demonstration Kit

Colorful Electrolysis -
Chemical Demonstration Kit, AP6467
Catalog Number
Colorful Electrolysis - Chemical Demonstration Kit
Product Description

By: Mike Shaw
West Stokes High School, King, NC

Demonstrate simple electrolysis in a very colorful and dramatic way on your overhead projector. A 9-V battery supplies the power and universal indicator provides the color show. As electrolysis occurs in the Petri dish, the pH changes at the anode and cathode are different. The solution around the cathode immediately turns purple as hydrogen gas bubbles are formed. At the anode, oxygen is produced and the solution turns orange/red in color. Across the entire Petri dish the entire spectrum of universal color changes occur reflecting the pH continuum created in the Petri dish. Teacher Demonstration Notes are included. Enough materials are included to perform the demonstration seven times.
Concepts: Electrolysis, pH.
Time Required: 15 minutes
Materials Provided: 9-V battery, battery clips, pencil leads, Petri dishes, sodium sulfate solution, universal indicator solution.


  • Petri Dish Electrolysis Video
    Petri Dish Electrolysis Video
    Build simple and inexpensive electrochemical cells in a Petri dish to compare the reactions of sodium sulfate, potassium iodide, and tin(II) chloride.
Additional Resources
Flinn Catalog/Reference Manual Page 376
Flinn Middle School Catalog/Reference Manual Page 431
P.O. Box 219, Batavia, IL60510



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