Magical Disappearing Ink Science Experiment

Some of you may have seen our happy new year post on Facebook, Instagram or Twitter and wondered how we did it. Others may just be looking for a disappearing ink science experiment that looks just like magic! Read on to find out how to make a message appear or disappear with fire.

You will need:

  • Adult supervision
  • A cup of water
  • A piece of paper
  • A blue pen
  • A thermochromic erasable blue pen such as these pens .
  • A long handled lighter
  • Metal tray larger than your piece of paper

Method:

  • Write your message with the normal blue pen.
  • Disguise your message by adding extra lines, swirls and boxes to your message using the erasable blue pen. This is more effective than simply colouring over the original message.
  • Place the piece of paper into the metal tray
  • Get your adult and a cup of water just in case!
  • Ask your adult to pass a flame over the message and see the erasable pen disappear.
  • Never play with fire and always make sure you do this experiment in a metal tray or on another heat proof surface.

The science bit:

    • The ink in modern erasable pens is ‘thermochromic’ which literally translates as ‘temperature colour’. The ink is blue normally but turns clear when it is heated. The ‘eraser’ on these pens creates friction which makes heat and makes the ink disappear. When you pass the flame over the ink it does the same thing.
    • Why not make a disappearing ink science experiment for a parent or teacher? Make sure a grown up always helps you with this science experiment.