I decided to turn it into skill experiment to test a few different substances and see what works best to clean old brown pennies. I remember unintentionally doing this one time with a mailboat of hot sauce from Taco Bell when I was in high school. That ’ sulfur where this experiment theme came from ! My friends & I thought it was so cool that the penny got sol bright.
Why Do Pennies Turn Brown?
Pennies are made of bull. When copper is exposed to oxygen it will corrode ( turn brown ) because of chemical reactions. The embrown coating is called patina. These are bull oxide molecules and they actually protect the alloy underneath. Over time, copper transitions from its glistening embrown color to a colored brown shade .
How to Clean Pennies:
If you are authentically wanting to know how to clean pennies, I have learned that the combination of vinegar and salt will get them really clean and shiny. specially if you scrub the pennies with that combination a bit. But for the sake of this experiment, we wanted to try some different substances to see what would work best for us. I let my kids help pick the different things to test .
We filled some cups with a small amount of different substances in our kitchen to see which one would get our dirty pennies the clean. I had my kids each take a guess at which thing would get the pennies the cleanest. They were way off, so it was playfulness to see which truly did get them clean. We let the pennies soak for a time, then put them on a newspaper towel to dry. future wipe or scrub the penny clean with paper towels .
Substances We Tested for Cleaning Pennies
When experimenting with how to clean pennies, we tested a variety of items, here are some ideas:
Lemon or lime juice
Put some of each substance in a a bowling ball or cup, adequate to cover the penny, then allow it to sit for a meter. We left ours for 30 minutes .
We took them out and wiped each one off on a paper towel. You can see the surface of the pennies change and become shinier. You can then rinse them with running urine and set them on a towel to dry .
Vinegar and lemon juice both work in truth well for cleaning pennies. But, catsup was the clear winners for our pennies, with soy sauce sauce next, possibly with a little more time they would have gotten a little moment cleaner .
This is a fun experiment to try with younger kids ! My kids of all ages were concern in the results, though. so if you want to do it with older kids, barely go deeper with the science !
Read more: How to calculate what is probability of getting same result 8 times in a row, when flipping coin 1000 times?
Use my Scientific Method Worksheets to extend this !
See flush more stem projects for kids .
now just for the sake of preserving history, hera is our original persona from the beginning time we tried this experiment about 10 years ago. 🙂
Category : Finance
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