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Question
Answer the following questions based on the extraction of aluminium from alumina by Hall - Heroult’s Process :
Why is powdered coke sprinkled on top of the electrolyte?
Solution
Coke while burning takes up oxygen from Al2 O3 (bauxite) and is converted into Co and also into CO2 .
- The CO produced also reduces Al2 O3 . This reduction process helps in purification of aluminium.
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