In the extraction of aluminium by Hall-Heroult process, purified \[A{{ – McqOptions

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1.	In the extraction of aluminium by Hall-Heroult process, purified \[A{{l}_{2}}{{O}_{3}}\] is mixed with \[Ca{{F}_{2}}\] to(i) lower the melting point of \[A{{l}_{2}}{{O}_{3}}\].(ii) increase the conductivity of molten mixture.(iii) reduce \[A{{l}^{3+}}\] into \[Al\left( s \right).\](iv) acts as catalyst.
A.	(i) and (ii)
B.	(i), (ii) and (iii)
C.	(iii) and (iv)
D.	(ii), (iii) and (iv)
Answer» B. (i), (ii) and (iii)

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