"Harold and Susan Vordos" wrote in message
. net...

"Ed Huntress" wrote in message
...

"LLBrown" wrote in message
...
snip---

Ah, well, now you've got me. It may be that there are copper ions in the
acid, if you've used it for that purpose before, and that they'll plate
out like electroless nickel.

That's what is happening. Zinc on the surface is displacing the copper in
solution, so it is, indeed, plating the copper. This process is
commonly used in refining where recovery of values is accomplished with
base metals. Zinc is amongst the best possible choices.

Harold

Thanks, Harold, and thanks to Carl (who owned up to being a chemist). I sort
of smelled like that to me, but doing chemistry by smell is not to be
advised. d8-)

So it sounds like there is some degree of dezincification and some degree of
copper plating going on, the relationship depending upon the state of the
hydrochloric acid solution. Interesting. It could almost get me interested
in chemistry.

--
Ed Huntress