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Chemistry Project on Chlorine & Gold

Ok, have a question for a chemistry paper that I need to write for school. I have to do a fifteen page paper on the effects of chlorine on gold and why does it have the effect it does. I have found the effects that it has but I have not found the reason for this chemical reaction. I have done a lot of research and still nothing. If you have any answers they would be really helpful, thank you

Nadia Abeyta
- ALB, NM USA
2001

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Nadia,

May I suggest you contact an 'Assayer' ...ie. an Assay Company and ask for the chief chemist. He/she would be able to answer your question, I'm sure. In Idaho and B.C. there are numerous Assaying Companies but I'm not sure you have any (or any gold mines who would have a lab and an 'assayer') in your neck of the woods. Can't help you any more. Sorry.

Freeman Newton [deceased]
(It is our sad duty to advise that Freeman passed away
April 21, 2012. R.I.P. old friend).
2001

I think that the reason for the reaction and any chemical reaction has to do with co-valent bonds of the atoms. If you look into Valent and co-valent or cation and anion(chemistry), you should get the general idea. If you understand what the 3 key parts of an atom are - then the electron shell of a gold atom may be short one electron, the chlorine atom has one too many electrons in its outer shell, these 2 atoms share the extra electron producing an "ionic bond" the 2 atoms then form a different compound maybe gold chloride. This is only one aspect of what could happen I don't know what the reaction is with gold and chlorine. If 2 chlorine atoms attach to the gold it would be gold dichloride or something like that. Water-H2O is hydrogen dioxide. It could also break some gold away to form an unstable compound that could more easily further react with other compounds. Gold is very stable because its electron shells are usually filled and aren't willing to "share". Chlorine is I think unstable and for some reason the atoms "like" gold.

David Domm
- Rochester, New York
2001

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May 27, 2009

I have had 3 9k gold Irish Claddagh rings. Each one has turned to a copper color. They are not plated. It is traditional for them to be 9k gold. I learned the following: At maximum concentration such as pure household bleach, chlorine is so reactive that 14k gold jewelry left in pure bleach solution for 24 hours will be destroyed beyond repair; in extreme cases the gold will be dissolved! DON'T EVER SOAK JEWELRY IN BLEACH!
Chlorine reacts specifically with the copper and nickel portions of gold jewelry alloys. Copper and silver are the primary alloys for yellow gold and nickel is the primary alloy for white gold. Chlorine dissolves the copper, or in the case of a white gold mounting for a diamond the nickel, and causes a perfectly good and often new piece of jewelry to break.
Reference this site, see if it helps you, www.jewelry1.com/CHLORINE.HTM

Cindy O'Donnell
- Wesley Chapel, Florida