R.C. Indicator!

C the Rainbow


This indicator is made from a Red Cabbage (R.C.) juice. It can be used to tell the different colors of the acids and bases, just like a pH strip would. The juice will turn purple for neutral substances, green for bases and red for acids.

Fun and Easy to Use!

This indicator is very safe and easy to use! In fact, it can be used by mostly anyone including middle school students because its non-toxic. All you have to do is pour a substance into the juice and watch the reaction take place.

Tested by Experts:

The Sci Guys: Science at Home - SE2 - EP4: Red Cabbage pH Indicator - Acid Base Indicator

The Science Behind It

Anne Marie Helmenstine, Ph.D., chemistry expert says that "red cabbage contains a pigment molecule called flavin (an anthocyanin)...very acidic solutions will turn anthocyanin a red color. Neutral solutions result in a purplish color. Basic solutions appear in greenish-yellow. Therefore, it is possible to determine the pH of a solution based on the color it turns the anthocyanin pigments in red cabbage juice. The color of a juice changes in response to changes in its hydrogen ion concentration.

Do It Yourself!