Question

The mass of. Carbon anode consumed in the production of 270kg Al metal from bauxite by hall process giving only carbon dioxide?

Answer 1

We assess the reaction...`Al_2O_3(s) + 3/2 C(s) +Deltastackrel(AlF_3"/"NaF)→ 2 Al(s) + 3/2 CO_2(g)`

Explanation:

The aluminum and fluoride salts are added to the reaction mix to depress the (high) metling point of alumina....even so, this is a very energy intensive reaction. Think about that the next time you throw away that aluminum foil you used to cook your spuds in (and you don't need foil anyway, just cook the scrubbed potatoes in their jackets!).

`"Moles of aluminum"=(270xx10^3*g)/(27.0*g*mol^-1)=10^4*mol`

And given the stoichiometry of the reaction, we produce a `(10^4*mol)/2=5000*mol` quantity of aluminum.

And thus we need an equivalent molar quantity with respect to carbon....

`7500*molxx12.011*g*mol^-1xx10^-3*kg*g^-1=90*kg` with respect to carbon.