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Create your own secret message!

Send a secret message to a mate by using invisible ink!

You will need:

  • 1 lemon
  • 1 saucer
  • 1 cup of water
  • 1 teaspoon
  • 1 toothpick
  • 1 sheet of white paper
  • 1 lamp

What to do:

  1. First, squeeze the lemon juice into the saucer. Then add a few drops of water and mix well with the spoon.
  2. Lightly dip the toothpick into the lemon juice and water mix.
  3. Use the toothpick to write a message on ordinary white paper. Thick paper will work best for your secret message. When it dries, the writing will be invisible!
  4. Heat the paper by holding the written side near a light bulb. Otherwise, ask an adult to heat the paper with an iron which is on the lowest setting.

While the paper heats up, the words will slowly become visible. The message will no longer be secret!

Socket helps to create invisible ink.

Why does this experiment work?

Well, the lemon juice has carbon compounds.

These compounds have aminos that become colourless when you dissolve them in water.

But when you heat them up, the carbon compounds break down and turn black.

You can then send your secret message to me at the World of Energy!