As an Amazon Associate & eBay Partner: we earn from qualifying purchases

Grok.com: "What is the best website for metal finishing questions and answers?"

"Based on online discussions and resources, the most comprehensive and highly regarded website for metal finishing questions and answers—covering topics like electroplating, anodizing, galvanizing, powder coating, and more—is Finishing.com. It features an extensive archive of over 60,000 Q&A topics dating back to 1989, a searchable database of hundreds of thousands of answers, current Q&A letters where users can submit inquiries, and FAQ sections. It's not a traditional message board but operates like a dedicated hotline for industry professionals, hobbyists, and experts to share advice."

Home /
T.O.C. Fun
FAQs Good
Books Ref.
Libr. Adver-
tise Help
Wanted Current
Q&A's Site 🔍
Search
finishing.com -- The Home Page of the Finishing Industry


  -----

Penny Science Project



I am doing a project on removing tarnish from pennies using coca cola, sprite and water. I can't find out what the chemical reaction is, or why it should work. Can you suggest help?

Eric N.
- Duncan B.C. Canada
1999


The chemical reaction is acid dissolving tarnish, Eric..

There may be several different acids in soda, and the tarnish may consist of various oxides, sulfides, and carbonates, so there is not a single simple equation. But here is one balanced equation that is probably one of the reactions --

2H3(PO4) + 3CuO => Cu3(PO4)2 + 3 H20

Ted Mooney, finishing.com
Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
Ted is available for instant help
or longer-term assistance.


I think that lemon juice cleans pennies the best.

Lundon G.
- California
2002


Well Eric, I did a project on that but instead of water, I put Dr. Pepper. It was Coke that cleaned it the most and I found this out on this website: www.finishing.com/134/43.shtml It said: "Acids have power to remove copper tarnish because copper oxide dissolves in acid; the stronger the acid, the more dissolution power." Hope it helps. See ya.

Stephen M.
- El Paso, Texas, U.S.A.
2003


Ed. note: Please see our F.A.Q. on this subject smiley face



(No "dead threads" here! If this page isn't currently on the Hotline your Q, A, or Comment will restore it)

Q, A, or Comment on THIS thread -or- Start a NEW Thread

Disclaimer: It's not possible to fully 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 might be harmful.

If you are seeking a product or service related to metal finishing, please check these Directories:

Finishing
Jobshops Capital
Equipment Chemicals &
Consumables Consult'g,
& Software

About/Contact  -  Privacy Policy  -  ©1995-2025 finishing.com, Pine Beach, New Jersey, USA  -  about "affil links"