Saturday, January 22, 2011

Science Sunday---Invisible Ink

This is a real neat science kit....with many fun experiments.
Today we started out learning about acid and bases...using the litmus paper included in the kit.
The projects are first "performed" as magic tricks and then are explained scientifically.
Gracie prepared 2 tests tubes. One with a water and citric acid solution and another with water and baking soda.
First we wrote on the paper with the base (baking soda solution). The paper immediately turned red....we then wrote over the red with the acid (citric acid solution)....the red "magically disappeared.
We learned how litmus paper works---this led to more experimenting with acid and bases.
We learned what happens with when you mix acid and bases.....
it makes a great reaction....and a quite messy reaction.
This also led to the discussion of writing with invisible ink.
We recently read a book where the heroine reads a message that was written with lemon juice.
We had to give it a try.
This is dangerous....no child, no matter what age, should do this without adult supervision.
(In fact, I lit my living room rug on fire doing this when I was 12 years old---luckily, that was all that caught on fire.)
Mark and Grace first wrote their names in lemon juice on regular computer paper.
We let the lemon juice dry---it was invisible.
I used one of my candles which has burned down quite low so that the paper would be a "safe" distance from the fire.
Placing the paper over the heat of the flame made the "invisible ink" appear, revealing writing.
Kim and Luke wandered in and needed to get in on the experiment.



The final invisible results....very fun science!!

Science Sunday

2 comments:

An Almost Unschooling Mom said...

Looks like a good kit - and some fun extensions. Good warning about the rug too!

Ticia said...

Glad to hear I'm not the only one who's messed up a rug, except I was an adult when I did it.

That looks like a super cool kit, I've been thinking about getting kits like that sometime, maybe I will soon.

Thanks for linking up to Science Sunday!