During the continuous operation of the Hall-Heroult electrolytic cell for aluminium extraction, the — Metallurgy and Isolation of Elements Chemistry Question

💡 Solution & Explanation

During electrolysis, oxygen ions migrate to the anode. The liberated oxygen reacts aggressively with the carbon of the anode at high temperatures to form $CO$ and $CO_2$ gases, continuously eroding and consuming the graphite rod, which must therefore be replaced.