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In the context of the Hall – Heroult process for the extraction of A l , which of the following statement is false ?

1. CO and CO 2 are produced in this process
2. Al 2 O 3 is mixed with CaF 2 which lowers the melting point of the mixture and brings conductivity
3. Al 3+ is reduced at the cathode to form Al
4. Na 3 AlF 6 serves as the electrolyte

Correct answer: Na 3 AlF 6 serves as the electrolyte

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