What are some other ways to indicate pH, and what colors do they yield? Students use a variety of indicators and unknown solutions to explore pH.

DIVIDE the class into cooperative groups. Each group should consist of four students with the following roles:

• Materials Handler: Distributes materials.
• Equipment Handler: Manipulates materials.
• Recorder: Records results.
• Speaker: Shares results with the class.

Have each group SELECT several solutions and indicators they want to test. Have the Materials Handlers distribute the materials to each group.

Have Equipment Handlers TEST all indicators with all solutions, while the Recorder RECORDS all results.

Have Speakers PRESENT their results. As a class, CREATE a chart to summarize each group's results.

What's Happening? Find out more about indicators and their ranges.

Challenge: Can you find other indicators in your kitchen or back yard? What indicators make the best testing strips? Be sure to share your results in our pH Exchange.