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pH on corrosion of copper

I am doing a science fair project on which pH level is most conducive to the corrosion of iron and copper. I'm in the process of doing the experiment and it seems like pH level 1 is most conducive to the corrosion of iron. the pH level one in the copper has crystals on it and it dulled. there are some dark spots on it. is this right? I also have to write a research paper. Any idea for a good researching spot?

Thanks,

Steph H.
student - Boston, Massachusetts, USA
2005

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Yes, low pH (acid) would be corrosive to copper. Sorry, but I can't understand your description of what you did and what you are seeing. A good researching spot would be your city library.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
2005

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A few hints:

metal + acid = metal salt as in copper plus hydrochloric acid yields copper chloride ions which will precipitate after they reach a saturation point. This is not a balanced formula, so you will have to do some homework on that.

Next, many libraries have a copy of Lange's Handbook of Chemistry [adv: on Amazon, AbeBooks, or eBay] or a copy of CRC Handbook of Chemistry & Physics [adv: on Amazon & AbeBooks & eBay] . You can go to the inorganic section under copper and it will give every known molecules of copper with color and shape. In my example, go to both cuprous chloride and cupric chloride, the +1 and the +2 valence state. Note that the dotH2O is attached water which makes a big difference also.

OK, enough hints, hit the library for a chemistry book and the cited references. Come back with specific questions.

James Watts
- Navarre, Florida
2005