Smiling like Sunshine: Science experiments with kids: Invisible ink

Friday, 8 July 2011

Science experiments with kids: Invisible ink

This experiment has been on my mind since I read it on an old supplement given by The Guardian. Defne LOVES lemon ;) so she was very pleased with experimenting with lemons.

We diluted some lemon juice with a little bit of water and then Defne used a cotton bud to draw/write using this mixture.
Apperantly she wasn't impressed as she just couldn't see what she was drawing!

When she was finished I put the papers in the oven for maybe a minute or so ( the oven was already scorching hot as I was baking yummy pizzas)
And then ....the magic happens!
 if you look carefully, you will realize she tried to write her name. She loved it!

The lemon juice is acidic so it weakens the paper.The acid remains in the paper after the juice  has dried. When the paper is held near heat the acidic parts of the paper burn or turn brown before the rest of the paper does. You can try it with other acidic liquids like orange juice or vinegar, too.

I also LOVE The Artful Parent's version "Invisible ink with crayon resist",on my project list for the summer holidays.

Happily shared with The Play Academy, Something for the weekend, It's Playtime, Kids Get Crafty, Preschool Corner, and Tot School


  1. These are indeed exciting and fun activities for kids! Just imagine all those secret messages you can write!

    Thanks for linking to Kids Get Crafty!


  2. I really like this idea, though I have to admit I'd be afraid I'd burn my house down!! :)

  3. Oh we love invisible ink! Endless possibilities when they reach the spying/detective stage! Thanks for popping it on the SFTW linky, could you possibly pop the link on here too? Thanks :)

  4. I never tried invisible ink but we did a project where we colored on white paper with white crayon and then painted over it. A magical message appeared!

  5. Very neat! I couldn't remember what you did to make it appear - thanks for joining It's Playtime!

  6. My son was the same way when we did this, he was so frustrated that he couldn't see his writing. Very fun in the end though.

  7. I think it's fun to write some messages for them to discover too. (That way I get to have a go too!)

  8. Jamie, my pleasure :)
    Allie,thanks for stopping by :)
    Cathy, yep, that would be great fun with older children :)


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