The minimum voltage required to electrolyse alumina in the Hall-Heroult process is (Given, o f G Al O 1520kJ mol ; o f G CO 394kJmol ) (AIIMS 2009)

In Hall-Heroult process, the following reactions occur 2 3 2 3C 2Al CO 4Al 3CO → 3 4Al 12e 4Al → o o o f 2 f 2 3 G 3 G CO 2 G Al O 3 394 2 1520 1858kJ o o cell G nFE o cell 1858 1000 E 1.60V 12 96500 x x