Our attempt to make hollow pennies didn’t turn out as planned. Which is another way of saying the hollow penny experiment failed, but since I documented our process I figured I’d share it and maybe you’ll try it and you can share better photos if things go according to plan.
I first read about making hollow pennies from the book, Why Is Milk White? & 200 Other Curious Chemistry Questions
It sounded simple enough and I thought I could make a penny necklace or earrings with our final product, but, well, you’ll see why I didn’t below.
I sanded down each penny at two opposite points, exposing the zinc and creating an entryway for the acid to dissolve the zinc, leaving only the copper shell behind.
Uh, yeah, I’m not going to be showing these off anywhere soon. I’m not going to toss them, though. Perhaps we’ll use them as raw material for placing on the rail road tracks this summer.
Please do try this at home and be sure to send me a picture of the results!