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Question
What is the role of cryolite (NaAlF6) in the electrolytic reduction of alumina in the Hall's process?
Solution
Cryolite acts as a solvent for the electrolytic mixture in the electrolytic reduction of alumina in the Hall's process.
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| 'Alumina (aluminium oxide) has a very high melting point of over 2000°C so that it cannot readily be liquefied. However, conversion of alumina to aluminium and oxygen, by electrolysis, can occur when it is dissolved in some other substance.' |
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