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9th grade electroplating science fair project
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I am in 9th grade and am doing a project about electroplating. I have looked everywhere for information; in public libraries, bookstores, and on-line bookstores, and the only book I've got so far is useless to me (about the most valuable info I was looking for all the book said about it was: "chemical compositions of various plating baths is available from many sources and need not be repeated here"!). All other sources were out of stock or would take to long to ship any book (my project is due at the end of this month).
As I have gathered more info, I've seen that many types of electroplating involved hazardous substances (I could deal with not touching acids but avoiding acid mists from the electrolyte would be a problem). I think maybe plating of nickel would be safest, as oposed to chromium or zinc which have cyanide.
What I would like to know is which types of electroplating would be safest, and if any are okay then which one and what type of electrolyte I would need, how much cathode and anode (on a small scale, to plate about as much as the handle of a fork or so), and how much current and voltage would be required.
Any help would be really appreciated. Thank you.
Andre G- Falls Church, VA
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Although I find it hard to believe that your library doesn't have an encyclopedia with a worthwhile entry under 'electroplating', you came to the right place, Andre. See our FAQs which are linked to as many letters and as deep a discussion as you wish.
But essentially, we suggest that you either copper plate or zinc plate your item, using copper wire as the source of copper or sanded down pennies as the source of zinc, vinegar as the electrolyte, with the following additives:
- some epsom salts to aid conductivity
- a little sugar as a brightening agent
- a drop of dishwashing liquid as a wetting agent
A 1-1/2 volt D-cell flashlight battery will supply enough current.
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 Ted Mooney, P.E. finishing.com Brick, New Jersey |
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Thanks Mr.Mooney. But just what can I copper or zinc plate onto based on your solution?
On the FAQ I found two experiments on electroplating. One had an experiment, where you would plate zinc into copper pennies, that had the same solution except on this one you said to add dishwashing liquid. I was just wondering which one would work better. Also, it said to clean the cathode, but isn't it necessary to clean the zinc?
The other one was to plate nickel into copper or steel and the solution was nickel chloride (is nickel chloride corrosive or hazardous?). It suggested not to do that one because chlorine gas may be released. Well, as part of my experiment, in which I test which factors make electroplating faster, I would increase the voltage. Would that cause more release of chlorine (I read that somewhere in this site)? Thanks again
Andre G- Falls Church, VA
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Your 9th grade science project should be an attempt to safely demonstrate principles, rather than to actually produce an electroplate suitable for industrial use, so I think you should plate onto coins: zinc plate onto copper coins like pennies, or copper plate onto dimes and quarters.
A drop of dishwashing liquid will do no harm. Whether it will do any real good in a 9th grade experiment is questionable: it just makes the water wetter. The cathode (the thing you are plating onto) must be absolutely clean; the anode (the material dissolving into solution) is much less critical.
I do not think you should do nickel plating, both because some people are allergic to nickel (nickel itch) and because any solution that contains chlorides (as nickel does) can accidentally produce chlorine gas at higher voltages under unusual circumstances. This is why we suggest using epsom salt (magnesium sulphate) rather than table salt (sodium chloride).
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 Ted Mooney, P.E. finishing.com Brick, New Jersey |
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THANKS a lot for all your help and advices. I'll do the experiment you suggested.
Andre G- Falls Church, VA
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Greetings Andre, I must really be getting old 
-- I remember doing this same type of project for my 8th grade science project.
If I remember correctly though, since I've always been around plating I had the "commercial" grade copper plating bath and I copper plated a nail. The feeling I got when it worked was amazing, a whole new world opened up to me when that happened and science became a very important part of my life. Once you plate that first object don't be surprised if you get this unstoppable urge to dive deeper into the whole realm of metal finishing, its a huge world and an extremely enjoyable one to be associated with. Good Luck to you young man, and hope to see you on the plating trails later in life (you never know).
Matthew Stiltner- Toledo, Ohio
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Thanks Mr.Stiltner :-)
On the FAQs, it said to leave the zinc in the vinegar for several hours so it would dissolve, and to have 100g/l of the zinc dissolved. (Tell me if I'm wrong, but when you say 100g/l, you mean 100 grams of the substance per liter of vinegar, right)? I left the zinc for several hours, and I'm sure it wasn't close to the amount it said. But I was just wondering if I connected the zinc to the positive side of a battery it would help to dissolve the zinc faster and in greater amounts.
Andre G- Falls Church, VA
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It would plate out about as fast as it dissolved, so it wouldn't help much. Further, you would probably lose some of the acidity, and that's a pretty precious commodity when you are deliberately using a very weak acid for safety reasons.
I'd let it dissolve a while, but I'd agree with you that the dissolved zinc probably doesn't approach 100 grams per liter.
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Ted Mooney, P.E. finishing.com Brick, New Jersey |
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Dear Mr. Mooney,
We are trying to electroplate zinc onto copper pennies for our science project-the effect of voltage on electroplating. We are using the recipe on your webpage. The copper is being plated but then disappears when taken out of the solution so that we can't accuratly weigh the pennies. Any suggestions would be appreciated.
Sincerely,
Jesse H and Ben D- Oakland, California, USA
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The electroplating is awfully thin, probably just a few millionths of an inch. Between wearing off and migrating into the copper it may appear to vanish. I think you are going to have a very difficult time weighing such a thin coating. But if you electroplate for several hours, or overnight, instead of a few minutes you might have a fighting chance. If you can get a science teacher to help you, you could use dilute sulfuric acid instead of vinegar and you could plate much faster, but it is too dangerous to do without training and protective gear.
A more interesting experiment might be the effect of current and time, since you would be working towards proving Faraday's Law.
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Ted Mooney, P.E. finishing.com Brick, New Jersey |
February 19, 2008
I am zinc plating pennies right now. Two things:
First, can you please tell me to which side of the battery does the penny have to be connected to, + or -?
Second, I made a solution by letting zinc sit in vinegar. The first time, I just put the penny in. The second time, using the same vinegar, I added salt and sugar. In about a day, I noticed that the clamp I connected the penny to the battery was almost completely eaten away. There was almost nothing left of the submerged part. The first time it was fine. Can you tell me why that happened?
- Daly City, California, USA
February 21, 2008
The object which you wish to plate onto is connected to the negative terminal of the battery. If you are doing this as a chemistry lesson rather than as play, you need to understand why, Dima, and it is explained in the FAQ you were looking at.
The solution is apparently far more corrosive with salt in it than with just vinegar in it.
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Ted Mooney, P.E. finishing.com Brick, New Jersey |
February 22, 2008
Thanks a lot. My science project was a complete success, and I got an award.
Dima A- Daly City, California, USA
February 22, 2008
Way to go, Dima. We're happy for you!
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Ted Mooney, P.E. finishing.com Brick, New Jersey |
August 22, 2008
What happened! I have recently done an electroplating experiment (12 year old Grade 7) and something really weird happened the first time! instead of the copper flowing over to the quarter from the penny the wires dissolved and the salt and vinegar solution got this green sludge in it! I want to know what went wrong because I'm currently doing the same experiment except its working the right way- the nickels getting covered with this black stuff. I just want to know what that green stuff was last time and why the solution got really powerful and dissolved everything! Thanks in advance.
Sam G.Student - Watauga,Texas, USA
August 22, 2008
Hi, Sam. Are you sure the voltage was never above 1-1/2 volts?
Regards,
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Ted Mooney, P.E. finishing.com Brick, New Jersey |
September 9, 2008
Okay, Like I am in the 8th grade and I am wondering how this experiment works, since I got several questions of course.
1) The first thing I don't get is that am I suppose to add vinegar, salt, sugar, and dish washing soup all together one after another?
2) if so, how long do I leave it like that? Am I suppose to stir it or something?
3) What materials do you suggest? A copper Penny, a copper plate, and copper wires?
4) what is a anode?
5) How long do I leave the circuit connected 'till I notice something change?
6) Does it matter type of salt I use?
Thank you for your time...i appreciate it
- Houston, Texas, US
September , 2008
Hi, Tony
1 & 2). Makes no difference. Just stir it a bit.
3). Our "How Electroplating Works FAQ" suggests plating a penny with zinc or a coin or brass key with copper. Copper wire is the best source of copper.
4). The anode is the positive pole in the circuit, and often it is made of the material that you wish to plate with, and supplies the metal by dissolving into the solution.
5. You'll see something happen in a few minutes with the zinc plating, it may take a half hour to see the copper plating start working.
6. You can use table salt.
Good luck and Regards,
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Ted Mooney, P.E. finishing.com Brick, New Jersey |