How to Use a Red Cabbage for a PH Tester

The pH of a liquid represents the concentration of hydrogen ions and is measured on a scale from zero, very acidic, to 14, very alkaline. One way to measure the pH is to use red cabbage juice as an indicator. The method is easy and inexpensive to use but does not offer the same degree of precision that an electronic pH meter offers.

Things You'll Need

• Red cabbage
• Water
• Strainer
• Paper
• Indicator chart

Instructions

1. Cut about one cup of red cabbage into small bits and put it into a blender with 1.5 cups of water. Blend.

2. Strain out any small pieces of cabbage so you are only left with the liquid after the cabbage is blended. The liquid should be purple in color.

3. Drip the liquid onto thin strips of paper and allow the paper to dry. The paper is now laced with the red cabbage juice indicator.

4. Dip the paper into the liquid you want to test.

5. Compare the paper to the pH chart to determine the pH of the solution. For example, if the paper turns dark red, the pH is between 3 and 4.

References

• Red Cabbage pH Paper
• Red Cabbage and pH

Resources

• Indicator Chart