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V.13 Electroplating. p.243-246. Electroplating. An electrolytic process in which a metal is reduced or “plated out” at a cathode The cathode is made out of the material which will receive the metal plating.
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V.13 Electroplating p.243-246
Electroplating • An electrolytic process in which a metal is reduced or “plated out” at a cathode • The cathode is made out of the material which will receive the metal plating
Electroplating solution contains ions of the metal which is to be “plated” onto the cathode • An inert electrode can be used as an anode, or the same metal which is to be “plated out”
p. 244: 73 • Electroplate iron with chromium.
Electrorefining • Process of purifying a metal by electrolysis • Diagram p. 245 • Zn & Pb will oxidize first, but most of the electrode is copper so then it will oxidize
Anode: Cu(impure)Cu2++2e- E°=-0.34V • Cathode: Cu2++2e- Cu(pure) =0.34V Cu(impure)+Cu2+Cu2++Cu(pure) =0.0V
Any bits of Ag, Au, Pt are spectators and will drop off Cu and form sludge • P. 246:78