QQuestion
Which of the following is not a constituent of the electrolytic mixture in the Hall-Heroult process?
(a) Al₂O₃
(b) NaAlO₂
(c) Na₃AlF₆
(d) CaF₂
✓Answer
(b) NaAlO₂
Explanation:
In the standard Hall-Heroult process, the electrolytic mixture consists of 20% alumina (Al2O3), 60% cryolite (Na3AlF6) and 20% fluorspar (CaF2). Hence, NaAlO2 is not a part of the electrolytic mixture.
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