Copper Etching

[christaj]

I'm using Ammonium Persulfate to etch Copper, and probably copper oxide.

I would like to know what I'm making, especially if there is any film that remains on the copper. (I rinse with H₂₀ afterwards)

(NH₄)₂S₂O₈ (aq)+Cu ->
(NH₄)₂S₂O₈+Cu₂O ->
(NH₄)₂S₂O₈+CuO ->

I haven't had a chemistry class since 1999 and am more than a little rusty.

Thanks for any help,
Andrew

[peter]

I think this is the main reaction:
(NH₄)₂S₂O₈ (aq) + Cu(s) -> (NH₄)₂SO₄(aq) + CuSO₄(aq)