posted by LT on .
During the electrolysis of an aqueous solution of CuSO4 with inert electrodes
(A) the anode loses mass and the cathode gains mass.
(B) the mass of the anode remains the same but the cathode gains mass.
(C) the mass of the anode decreases but the mass of the cathode remains constant.
(D) the anode and the cathode neither gain nor lose mass.
(E) both electrodes gain in mass.
I was thinking in Electrolysis of CuSO4(aq)
Anode: 2H2O O2(g) + 4H+1 + 4e-1 -1.23V
Cathode: 2 Cu+2+ 4e-1 2Cu + 0.34V
Overall: 2H2O + 2 Cu+2 O2(g) + 4H+1 + 2Cu E° = -1.02V
that it would be D because it doesnt really change in either
In the electrolysis of CuSO4, isn't Cu plated out on the - electrode?
what do you mean by plated
Electrolysis is used for plating one metal onto itself or onto another. For example, one can buy silverware to eat and cook with (most people use stainless steel) that is essentially pure silver ( and pay a high price for it--real silver ware has the notation sterling silver on it) OR one can purchase the less expensive silver plate in which a thin layer of silver or gold is plated onto a base metal of some kind. Obviously that is much much cheaper. Baby shoes are "bronzed" that way (by electroplating). So by plating Cu, I mean Cu^+2(aq) + 2e ==> Cu(s) and the copper is plated onto the host electrode. In fact, copper metal is refined that way, from impure copper to relatively pure copper by electroplating it onto a very thin piece of copper foil. The impure copper goes into solution at one electrode and plates out at the other electrode. And the silver and gold impurities are left as a sludge in the vessel and is refined. Often the silver and gold recovered more than pays for the electrolysis of the copper.
B,because in this type of reaction the anode does not ionises and remains the same but due to mthe ionisation of the CuSo4 soln. the cathode gains mass and increases in sizi.