Well, I can’t remember what number science experiment we are on, but this one also came from our Mind Blowing Science kit.
First, we filled two cups with a little water. M added baking soda to one and citric acid to the other. We labeled them A for acid, and B for base. We also marked two q-tips so we wouldn’t accidentally put one of them in both the base and the acid.
Then we took out some “goldenrod” paper that came in the kit. M dipped one q-tip into the acid cup and drew a little on the paper. At first it simply looked like a darker shade of orange, but as we watched it turned into a deep red.
When M dipped the other q-tip into the base solution and drew over the red, it erased the red and the paper was goldenrod again (really, why can’t they say dark yellow or light orange?).
And then we had fun drawing invisible pictures with the base solution and making them appear with the acid solution. M expected more of a “wow” with this experiment and was a little disappointed that it was only changing to one color. However, he still had enough fun with this that he played around with it for quite a while.
So, here’s the deal… goldenrod paper has a chemical in it that is an acid indicator, and it turns red when it comes in contact with acid. The base solution of baking soda neutralizes the acid and erases the red marks. Apparently you can do this experiment with cranberry juice too! Hopefully we’ll get around to trying that one sometime soon.
And then, of course, came the dumping everything in the tray and watching it foam up. And then a half hour of playing with more baking soda and a little vinegar. It really never gets old does it? :)
Well, it doesn’t if you are three years old. :)
Check out more science at Ticia’s Science Sunday post!
Have a beautiful day! :)