For each substance listed below, explain its significance in the extraction of aluminium:
(a) Bauxite, (b) Sodium hydroxide,
(c) Cryolite, (d) Graphite.
(a) Bauxite is the most common ore of Aluminium.
(b) Sodium hydroxide is used for the purification of Bauxite by Baeyer’s process.
(c) Cryolite is added to pure alumina to decrease the melting point or fusion temperature of pure Alumina.
(d) Graphite acts as anode