Questions on Extraction of Aluminium from Bauxite

Questions on Extraction of Aluminium from Bauxite

Answer the following questions regarding the extraction of Aluminium from Bauxite ore.

a) i) State the formula of Bauxite ore.

ii) Which property of Bauxite makes it react with Sodium hydroxide.

iii)The process adding Aluminium hydroxide crystals to dil. Sodium aluminate to precipitate out Al(OH)₃ is called seeding/smelting.

b) i) Mention any one difficulty faced during the electrolysis of Alumina.

ii) State the composition of the electrolyte taken the Hall Heroult’s process.

iii) Give one advantage of adding Cryolite to alumina in the above process.

c) i)Give reason why Graphite electrodes are replaced continuously in this process.

ii) What are the precautions to be taken to prevent the heat loss during the process.

iii) Give balanced equation for the electrolytic reaction that takes place at cathode.

           iv) Name the products formed at anode other than Oxygen.