This is mainly because of the large amounts of electrical energy used in the extraction process. Aluminium oxide is insoluble in water, so it must be molten to act as an electrolyte. However ...

Aluminum extraction requires temperatures of 1,000 o C and a lot of energy ... If left unprotected, iron is transformed by the corrosive process of rusting into iron oxide. When that happens, the ...

iron is extracted from iron oxide by heating with carbon gold is found uncombined in the Earth's crust aluminium is extracted from aluminium oxide using electrolysis. The list shows part of the ...