Reducing gold from an oxidation state of +3 to metallic gold has a potential of +1.40. Reducing lanthanum from an oxidation state of +3 to neutral lanthanum has a potential of -2.52.
(1) In this galvanic cell, which element is being oxidized and which is being reduced?
In electrochemical cells, the electrode with the higher reduction potential is reduced. In this case, gold has the higher reduction potential and is therefore reduced. Lanthanum is oxidized.
(2) Identify the cathode and the anode of this cell.
Reduction occurs at the cathode of the cell. The cathode must then be gold and the anode lanthanum.
