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a) Electrolysis
b) Al2O3.2H2O
c) i) Iron (iii) oxide
ii) silica
ii) Add hot concentrated sodium hydroxide (NaOH). Silica and alumium oxide (Al2O3) dissolves. Filter iron (iii) oxide. Bubble Carbon (IV) oxide (CO2) through the filtrate to precipitate aluminium hydroxide. Filter to obtain aluminium hydroxide as a residue
d) It lowers the melting point of Aluminum oxide
e) The reaction of aluminium with oxygen forms a firm layer of aluminium oxide
The layer prevents aluminium metal from further attack.
johnmulu answered the question on February 21, 2017 at 07:14
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