Paper 2 · November 2013 · Electrolysis and electroplating
Molten lead(II) bromide is electrolysed using inert graphite electrodes. Which equation represents the reaction that occurs at the cathode?
A2H2O -> O2 + 4H+ + 4e-
B2Br- -> Br2 + 2e-
CPb -> Pb2+ + 2e-
DPb2+ + 2e- -> Pb
Explanation
In molten lead(II) bromide, Pb2+ ions are reduced at the cathode: Pb2+ + 2e- -> Pb.
Derived from ZIMSEC Chemistry 5071/2 Paper 2 Theory, November 2013, Q4