Red Cabbage Indicator

Something colourful with kitchen items that can be used to show how acidic (or basic) something is.

What you need:

  • red cabbage
  • water
  • blender
  • food or chemicals to test for acidity, eg. lemon juice, vinegar, shampoo, household cleaner, tomato, egg white

What to do:

  1. Put three or four red cabbage leaves into a blender. Fill it to half way with water and blend.
  2. Strain the cabbage solution, collecting the liquid.
  3. Put the liquid into glasses.
  4. Add a few drops of whatever you want to test for acidity. Vinegar, baking soda and lemon juice are good ones to test.

What happens:

An indicator is a liquid that will tell you if something is an acid or a base. When something acidic is put in red cabbage indicator, it turns pink. When something is a base, it turns green or blue. pH is the measure of how acidic something is. Anything that is less than 7.0 is an acid, anything that is greater than 7.0 is a base. 7.0 is called neutral.

 

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