Red cabbage contains a chemical called anthocyanin. This pigment is a natural acid-base indicator. It is blue in neutral substances, like plain water. When an acid like lemon juice gets in the water, ...

Make an acid-base indicator. Dr Yan uses some very colourful science to find out what's acidic in his kitchen. Take 1/4 red cabbage ... pH higher than 7 is basic. Our test implies that lemon juice ...