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Q&As since 1989


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Acids and elements

I'm an amateur trying to design a cheap way to analyze scrap metal (non quantitative). I'm looking at electrophoresis. Where can I find tables or lists giving which acids (or bases) will dissolve which elements?

David Smith
amateur - Sacramento, California, USA
2004

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An interesting idea, but I am not sure how it will work. Scrap metal comprises many elements (possibly as many as 15-20)and to use electrophoresis will present problems. You will need to find a suitable solvent that will impart differential level of charge onto each element. There are systems available that will differentiate between some stainless steels by measuring their corrosion potentials in a known solution, which is some way to what you want. I think this technology could adapted to help you in a limited way. You can also use flame spectroscopy to identify single element metals, as they give off different colours in flames. If you do succeed, you may be able to make a fair amount of money from scrap merchants.

Trevor Crichton
R&D practical scientist
Chesham, Bucks, UK
2004