Electrochemical Chameleon

iconThis lab developed by the Schlenker Group  dramatically demonstrates the electrolysis of water and proves the underlying chemistry.

Normal tap water (H2O) is electrolyzed using a common 9-volt battery Epsom salt. The H2 and O2 gases that are produced are isolated and collected safety in separate containers. A natural anthocyanin pH indicator extracted from red cabbage is used to show vividly color changes at the positive and negative terminals of the battery during the water splitting process.

  • Anode H30+ and O2
  • Cathode OH- and H2

Download the complete lesson plan:

The Electrochemical Chameleon Lab CEI

Exploratorium Electrolysis Demo

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