-- The Home Page of the Finishing Industry

on this site
current topics

60,000 Q&A topics -- Education, Aloha, & Fun

topic 4361

Information on cleaning a penny for science


Hi my friend and I are doing and I are doing a science project for school and we would like to know what cleans a penny the best and why? can you send us information about pennies and the history behind them

Also can you send us peoples names and email addresses who know a lot about pennies/copper places in the new York area where we can go to find out about pennies, and a web site we can go to about pennies and copper we tried using many household substances and we found that ketchup and "Zud" [linked by ed. to product info on Amazon] w/ water cleaned a penny the best can you tell us why this my have happened and why these items cleaned it better than vinegar and copper polish.

Danielle M [last name deleted for privacy by Editor]
- Suffern New York

affil. link
"Naked Eggs and Flying Potatoes: Unforgettable Experiments that Make Science Fun"
by Steve Spangler
from Abe Books
info on Amazon

affil. link
"Award Winning Science Fair Projects"
from Abe Books


affil. link
Children's Arts & Crafts


The question of cleaning pennies has been raised many times here, Danielle; please see our FAQ on cleaning pennies. You can probably find info about the history at the U.S. Mint website at

I haven't used 'Zud', but there may be some indication on the label if it contains sulfamic or oxalic acid, which is often used in metal polishes.

The surface of an old penny has copper oxides on it, that you are attempting to remove with acid. Most weak acids have some power to dissolve copper oxides, but need chloride in the mix. Ketchup has a lot of salt in it, which makes chloride ion available; ketchup also has vinegar in at as well.


Ted Mooney, Teds signature
Ted Mooney, P.E. - Pine Beach, New Jersey
Striving to live Aloha


i used grapefruit juice and that was my number 1 thing I think it is the citric acid that was it but I don't understand it at all

Angela O [last name deleted for privacy by Editor]
- Edinburg Texas


I am also doing a science project on cleaning pennies, I am using different kinds of pop, either 7-up, coke, sprite, Pepsi, and root beer. I am doing two cups of each liquid, either pennies before 1983, or after, because before 1983, they were made of copper, now, they make them out of something else.

~good luck~

Somer K [last name deleted for privacy by Editor]

- Langlet, Washington

Pennies are cleaned by using vinegar\salt\water. I know because I already tried it.

Melinda J [last name deleted for privacy by Editor]
- Miami, Florida


I did this project for my science project and I experimented with Coke, Diet Coke and Lemons Diet Coke and the coke works better because of the sugar and the acids it has!

thanks bye

Alfredo S [last name deleted for privacy by Editor]
- Mpls, Minnesota

Note to students with science projects: Please see our FAQ on Cleaning Pennies; it will tell you everything you need to know! smiley

this text gets replaced with bannerText
spacer gets replaced with bannerImages

Q, A, or Comment on THIS thread SEARCH for Threads about ... My Topic Not Found: Start NEW Thread

Disclaimer: It's not possible to diagnose a finishing problem or the hazards of an operation via these pages. All information presented is for general reference and does not represent a professional opinion nor the policy of an author's employer. The internet is largely anonymous & unvetted; some names may be fictitious and some recommendations may be deliberately harmful.

  If you need a product/service, please check these Directories:

JobshopsCapital Equip. & Install'nChemicals & Consumables Consult'g, Train'g, SoftwareEnvironmental Compliance

©1995-2020, Inc., Pine Beach, NJ   -   About   -  Privacy Policy
How Google uses data when you visit this site.