Question
In the commercial electrochemical process for aluminium extraction the electrolyte used is
A.
$$Al{\left( {OH} \right)_3}$$ in $$NaOH$$ solution
B.
an aqueous solution of $$A{l_2}{\left( {S{O_4}} \right)_3}.$$
C.
a molten mixture of $$A{l_2}{O_3}$$ and $$N{a_3}Al{F_6}$$
D.
a molten mixture of $$AlO\left( {OH} \right)$$ and $$Al{\left( {OH} \right)_3}$$
Answer :
a molten mixture of $$A{l_2}{O_3}$$ and $$N{a_3}Al{F_6}$$
Solution :
$$A{l_2}{O_3}$$ is electrolyte, while $$N{a_3}Al{F_6}$$ is used to decrease the melting point of $$A{l_2}{O_3}$$ and to increase the conductivity.