Aluminium is extracted from bauxite using the process of electrolysis. Bauxite is a naturally occurring mineral that contains a mixture of aluminium, iron, titanium, and silica. The first step in the extraction of aluminium from bauxite involves the purification of bauxite by removing any impurities. This is done by treating the bauxite with sodium hydroxide solution to produce a solution of sodium aluminate.
Next, the purified solution of sodium aluminate is subjected to electrolysis in a cell called Hall-Heroult cell. In this cell, the purified solution of sodium aluminate is mixed with molten cryolite, which acts as a solvent to lower the melting point of the aluminium oxide. The mixture is then electrolyzed at high temperatures to separate the aluminium from the other elements present in the solution.
During the electrolysis process, aluminium ions are reduced at the cathode, forming liquid aluminium metal, while oxygen is produced at the anode. The liquid aluminium is then siphoned off from the bottom of the cell and sent for further processing to obtain pure aluminium metal. Therefore, the correct answer is bauxite.