# The mass of carbon anode consumed(giving only carbon dioxide) in the production of 270Kg of aluminum metal from bauxite by the Hall's process is

$(a)\;90Kg\qquad(b)\;180Kg\qquad(c)\;270Kg\qquad(d)\;540Kg$

$2Al_2O_3+3C\rightarrow 4Al+3CO_2$
$\therefore$ Carbon required $=\large\frac{12\times 3\times 270}{4\times 27}$
$\Rightarrow 90kg$
Hence (a) is the correct answer.