Make your own cabbage indicator
- make your own pH indicator–use a blender to mix one part chopped red cabbage with two parts boiling water and use the juice to test different solutions.
- Cook the mixture over medium heat, long enough for the water to absorb the purple pigment from the cabbage (approximately 15 minutes).
- Strain the cabbage, reserving the liquid.
- Acids will turn the pigments in the indicator to a reddish color; bases will turn the pigments bluish or yellow-green.
- Consider testing:
- Orange Juice
- Pickle Juice
- Tomato Sauce
- Window Cleaner
- Turmeric powder
Just add a dropper full of the household substances you’ve chosen to a small amount of cabbage indicator and see what happens
Information to share with students
1.red cabbage contains a chemical called anthocyanin that changes color depending on the acidity of its environment. In an acidic environment it is reddish-pink, in a neutral environment it is purple, and in a basic (or alkaline) environment it turns bluish-green and even yellow
Reference Links for this activity: https://www.scientificamerican.com/article/bring-science-home-cabbage-chemistry/