Easy Science Experiment: Cleaning Pennies

This morning our science experiment was so simple and fun I wanted to share! Cleaning pennies! Yeah, it doesn’t sound fun but my kiddos loved it, and it is harder than you think 😉

First I dug around for dirty pennies (seems that’s all I had in my wallet ha!). Then you will need soapy water (optional), vinegar, salt and a dropper. We only had a turkey baster, one of these days I will get a cute little dropper for our science experiments! This is what my set up looked like:

Here are the dirty pennies:

First I let the kids try to wash the pennies in the soapy water. It didn’t work of course 🙂

Then we discussed that it wasn’t really dirt causing the pennies to look dirty. It is a chemical change that has happened when the copper in them has reacted to the oxygen in the air which forms copper oxide. The only way to remove the copper oxide from the pennies is with a chemical reaction. The vinegar will react with the copper oxide to dissolve it! The kids were now pretty excited to get started. We used some salt to add grit for “scrubbing” the copper oxide with the vinegar.

After sprinkling on the salt we dropped the pennies with vinegar.

Next lots of cute little fingers scrubbing the pennies in vinegar.

It worked!

Thanks for stopping by!
Johanna 🙂