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Redox and electrochemistry — Question 56

Original QCE Vault practice · 4 marks

Q56 · Practice questionComplex familiar4 marks

QUESTION 56 (4 marks)

Molten aluminium oxide is electrolysed. Aluminium ions require three electrons per atom. A laboratory cell produces 2.70 g of Al at 5.00 A with 100% current efficiency. Use M(Al)=27.0 gmol−1 and F=96485 Cmol−1.

a) Write the cathode half-equation. [1 marks]

b) Calculate the required time in minutes. [3 marks]

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