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Student needing help with plating copper onto quarters

Thanks,

Michael C.
student - Richland, Washington, U.S.A.
2004

HI I'm a 7th grader and wanted to do a science fair project by plating copper wire onto quarters. First I clean the copper and quarter with toothpaste and carry them with gloves then I make a solution of vinegar [in bulk on eBay or Amazon], salt, and a little bit of antifreeze (propylene glycol). Then I take a Duracell D battery and connect to the positive terminal insulated copper wire with an alligator clip I connect to the wad of copper wire I then place that in the solution, then I take the negative terminal of the battery and connect insulated copper wire with an alligator clip and put the quarter on that clip and place it in the solution, after about 1 hour I comeback and it is coated with black, so I scrub it with toothpaste however the coating is very thin and quite a lot comes off, so please could someone tell me how to fix this or if plating something else would be better and how to do that.

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2004

You would be better off plating zinc onto a copper penny. Search this site, the method is documented here.

James Totter, CEF
- Tallahassee, Florida

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PLEASE I COULD REALLY USE SOME HELP THANKS.

MIKEY C.
- Richland, Washington, USA
2004

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2003

Two things, Mikey...

First, if your project was to demonstrate how cars work, you would not expect your 7th-grade science project car to actually go 240 miles per hour, or comfortably transport a family of 8 through blizzard and sandstorm, would you? Please don't expect your electroplating experiment, using household chemicals rather than proprietary and toxic chemicals, to rival the results of an electroplating factory. If you can get a little bit of coppery color on the quarter, you've done your job!

Does your plating solution look faintly blue or is it clear as water? If it is faintly blue then you have some copper dissolved in solution and it should work. If your solution is still water clear, there is no copper in it so when you try to electroplate, you cannot deposit copper, you can only 'burn' the quarter.

So if the solution is clear, use two batteries instead of one and run some scrap parts, ignoring the brown smut, until you have a bit of blue color in the solution, indicating there is dissolved copper available. Then start over with one battery and a shiny quarter again.

If your family has copper-bottom pots or something else that is old and oxidized copper, you could clean it with vinegar and salt and wring out the blue to get some solution with copper in it. Good luck!

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