A New Field
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Recipe

Red cabbage pH dye

A pH-sensitive dye that shifts from pink to blue to green as acid or alkali are added.

Every A New Field recipe has been run in a domestic kitchen or community hall. Read the safety notes before you start and adapt for your venue.

What you’ll make

Lilac to pink (acid), blue (neutral), green (alkali). Poor lightfastness.

Flexible slots (flex around your material)

  • Pigment

    Natural pigment / dye1/2 head

    Coloured plant, mineral or animal matter. Yields colour in water or alcohol.

    Examples Red cabbage

  • pH shifters

    AcidAlkalito experiment

    Mild household acids. Adjusts pH, curdles milk, releases pectin. Mild household alkalis. Raises pH, makes milk glue, fixes some dyes.

    Examples Vinegar, baking soda

Fixed ingredients

  • Water · 1L

Equipment

  • Large pan
  • sieve
  • small jars for experiments.

Refinements and variations

  • A child-friendly chemistry lesson disguised as dye.

Source notes

Classic school chemistry demonstration.