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How to get started with Chemistry for younger kids: How to make invisible ink - STEM

Hello everyone,

Thank you for tuning in to this article.

If you are reading this article today, it may be because you love STEM, have younger children who are 3-4 years old and older and want to teach him/her a little bit of chemistry with hands-on experience at home.

You have heard or seen those movie with spies (in the middle-age or James bond, etc) where they transmit data or secret information with special code, secret coded USB drive and more. Today, the game will not be that sophisticated, but we'll see how to transmit an invisible message on a piece of paper.

Materiel to build the invisible ink

To do so, we need to gather the following materiel:

  • One piece of white paper (It may be the one you use to print at home or at your office)

  • One lemon

  • A small bowl or cup

  • A little brush

Steps to create a the invisible ink with the lemon

  • Pick up the lemon

  • Cut it

  • Press the lemon in a bowl

  • Plunge the brush in the bowl and write a message on the white paper

  • Let it dry. The paper will seem to be virgin.

Make the message appear on the paper

You have different ways to make your message appears on the piece of paper.

  • You can take the paper in front of a light bulb or a lamp to see the message previously written with the lemon juice

  • Or you can put the paper in a pre-heated oven (375deg F) and leave it there until you see the message. About 20-30 minutes later. You can remove the white paper from the oven. Make sure to do this with a adult and a pair of mitten.

You can now play games with your friends and family to transmit secret messages that nobody should know.

If you or your kids like the article on how to make invisible ink with a lemon, please leave a comment, like the article and share it on social medias with your friends and family.

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