ABSTRACT
Although aluminum is a metal, it does not occur in a metallic state in nature. This is best explained by the fact that the reduction of aluminum salts or oxides to Al0 is an extremely endothermic process (for the reaction Al2O3 → 2Al0 + 1.5O2, ∆G0 is approximately +377 kcal mol−1 or +1578 kJ mol−1). Commercial production of aluminum metal involves electrolysis of molten Al2O3 in cryolite (sodium aluminum uoride) at high temperature.
