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The Best Penny Cleaners?

Hi, my son is conducting the well known experiment in high school with cleaning the copper pennies. My question is this, you said pennies after 1982 may dissolve in bleach, and I imagine in some of the other corrosive substances we have chosen. So in order to get an accurate reading, we should be sure all our tarnished pennies are between the years 1943 and 1982? We wanted to use acetone ⇦ this on eBay or Amazon [affil links] Warning! highly Flammable! as one of our substances, but you know what happens when you put pure acetone ⇦ this on eBay or Amazon [affil links] Warning! highly Flammable! in a plastic solo cup. Will it effect our results if we use a coffee cup instead for that one penny? Thanks for any help provided.

Jennifer S.
Student's Mom - Albany, Ga USA
August 26, 2008

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Hi, Jennifer. Hopefully you have already seen our "Cleaning Pennies FAQ" which attempts to answer all of the questions we could anticipate. Yes, I think only pre-1983 pennies should be used for this experiment. The coffee cup will almost surely have no effect but, since you are asking and wondering, you now know that you must note the use of it in your procedure :-)

Regards,

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
August 27, 2008

To avoid any problems, go to the dollar store and buy the required amount of small cheap glass bowls. I would call them fruit cups. They will not enter into any reaction with anything that you should use as a cleaner.

James Watts
- Navarre, Florida
August 28, 2008