Sunday, November 6, 2016

Red Cabbage pH Indicator

A simple pH indicator can be made from Red Cabbage. It is useful to estimate the pH of substances and to make your own Litmus paper. The Red Cabbage indicator will be red with low pH (acidic), blue with high pH (basic) and various shades of purple in between.

Directions for Large Volumes:


  1. Cut up one Red Cabbage into strips less than 1 inch wide
  2. Place in large pot and cover with water
  3. Boil until water turns purple and cabbage turns white-ish
  4. Let steep for 30 minutes
  5. Strain through sieve
  6. Store liquid in fridge
  7. pour into small containers for experiments

Directions for Small Volumes

  1. Chop Red Cabbage into small strips
  2. Heat up on cup of water in the microwave
  3. Put cabbage into boiling water
  4. Let steep for 30 minutes
  5. Strain through sieve
  6. pour into small containers for experiments

Directions for Litmus Paper

  1. Cut open Red Cabbage
  2. Blot with a coffee filter to completely dampen
  3. cut into small strips for experiments
Neutral

Acidic

Basic