Invisible ink

Write secret messages with homemade invisible ink! All you need is some basic kitchen items and lemon juice.

You’ll need

  • Half a lemon
  • Water
  • Cotton bud
  • Spoon
  • Bowl
  • Plain white paper
  • Lamp or torch

Important tip

Make sure your kids aren't holding the paper too close to something too hot, as they might hurt themselves or burn the paper!


  • 1

    Squeeze the lemon juice into a bowl and add a few drops of water.

  • 2

    Get your kids to mix the water and lemon juice together.

  • 3

    Dip your cotton bud into the juice. Write a message onto the white paper.

  • 4

    Wait for the juice to dry so it’s totally invisible.

  • 5

    When the paper is dry, carefully heat it by holding it close to a torch or a bulb, revealing your secret message!


So how’d that happen?

The lemon juice oxidises and turns brown when it's heated, so then you can read the message!




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