elementcollector1
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Rhodium plating darkening?
I purchased a rhodium-plated pewter jewelry piece over Amazon from Beadaholique recently. Wanting to extract the rhodium plating as foil, I filed a
small amount off to reveal the pewter underneath and placed this in HCl. The area that had been scratched (or rather deformed, as this metal is very
soft) immediately began bubbling, as expected. However, a few days later the rhodium has turned dark. What is going on here? Rhodium, to my knowledge,
is far too inert to react with normal HCl. Is the lead or tin making a double salt?
Elements Collected:52/87
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bbartlog
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If the exposed bit is being oxidized it may create some small electron flow that allows the rest of the piece to act as a cathode, so that something
is getting plated out of the solution and on to the rhodium. What that would be, however, I don't know.
The less you bet, the more you lose when you win.
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elementcollector1
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Quote: Originally posted by bbartlog  | | If the exposed bit is being oxidized it may create some small electron flow that allows the rest of the piece to act as a cathode, so that something
is getting plated out of the solution and on to the rhodium. What that would be, however, I don't know. |
Could be lead - color about matches...
Elements Collected:52/87
Latest Acquired: Cl
Next in Line: Nd
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