Why does aluminium form at negative electrode during electrolysis

The negative electrodes (cathodes ) and the positive electrodes (anodes ) are made of graphite, a form of carbon. During electrolysis: positively charged aluminium ions gain electrons from the cathode, and form molten aluminium. oxide ions lose electrons at the anode, and form oxygen molecules.

metals are good conductor of electricity. it has free electrons on their surface. according to electron pool theory, each atom present in a metal crystal losses all of its valence electron and as a result a pool of free is form. these pool of electrons are free to move and   conduct electricity easily   while making metal as good conductor.

the correct answer is a. the ability of electrons to flow throughout the metal.

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