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Author Topic: How does salt and vinegar work to clean tarnished metal?  (Read 13235 times)

Offline JP

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This is inspired by the question on using vinegar to clean rust off metal: http://www.thenakedscientists.com/forum/index.php?topic=40446.msg363843#msg363843

The last time I had to clean some tarnished metal (I believe it was brass), I Googled around for instructions and came across a few sites saying that mixing salt and vinegar would work (with flour to make it a good scrubbing paste).  Lo and behold, it did!  I also recall that as a child, I would often drop dirty pennies into salt and vinegar in order to make them look shiny and new.

So aside from tasting great on chips (either the American or British varieties), what chemistry makes this combination so good at cleaning metal?


 

Offline Bored chemist

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How does salt and vinegar work to clean tarnished metal?
« Reply #1 on: 02/08/2011 19:37:00 »
CuO + 2 CH3 COOH --> Cu(CH3COO)2 +H2O

You get copper acetate and water. The salt also acts as a complexing agent but the main effect is a weak abrasive.
 

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How does salt and vinegar work to clean tarnished metal?
« Reply #1 on: 02/08/2011 19:37:00 »

 

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