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Questions
Explain with reason:
In the electrolytic reduction of alumina, the graphite anode is gradually consumed.
Explain with reason:
Why the anode has to be replaced from time to time in this process?
Solution
In the electrolytic reduction of alumina, the graphite (anode) is oxidised by oxygen to CO and further forms CO2, so it is consumed and has to be replaced from time to time.
\[\ce{2C + O2 -> 2CO}\]
\[\ce{2CO + O2 -> 2CO2}\]
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