When certain plants come into contact with acids or bases, their colors change! These changing plants are acid-base indicators, and they are generally alkaline or acidic, so when they come into contact with things that have a totally different pH, their colors change.
Test for Acids and Base using flowers
Red Cabbage Chemistry
Berry pH paper
Identify which flower is acid-base indicator: Tulips, pansies, and roses, etc…
Identify why berries like blackberries, blueberries, strawberries are pH indicators.
Understand why the colour changed due to the soluble pigment called anthocyanin.
Try testing out other liquids like milk, soda, or fruit drinks to find out which ones are acidic and which ones are basic.