Q.
The mass of carbon anode consumed (giving only carbon dioxide) in the production of 270kg of aluminium metal from bauxite by the Hall process is (at. mass of Al=27)
(d) In Hall and Heroult process, 2Al2O3+4C→4Al+2CO2+2CO
but for the removal of only C 02, following equation is possible. 2Al2O3+3C→4Al+3CO2 =363×12=1084×27 ∴ For 108 g of Al, 36 g of C is required in above reaction. ∴ For 270×103 g of Al required amount of C 10836×270×103 =90×103g=90kg