In the metallurgy of aluminium ________________.
(i) is oxidised to .
(ii) graphite anode is oxidised to carbon monoxide and carbon dioxide.
(iii) the oxidation state of oxygen changes in the reaction at the anode.
(iv) the oxidation state of oxygen changes in the overall reaction involved in the process
The answer is the option (ii). The graphite anode is oxidized to carbon monoxide and carbon dioxide in the process of metallurgy of aluminium .