JEE Main202224 Jun 2022Evening ShiftChemistryGeneral Principles and Processes of Isolation of MetalsActual
Which of the following chemical reactions represents Hall-Heroult Process?
Options
- ACr 2 O 3 + 2 Al → Al 2 O 3 + 2 Cr
- B2 Al 2 O 3 + 3 C → 4 Al + 3 CO 2
- CFeO + CO → Fe + CO 2
- D2 Au CN 2 - aq + Zn s → 2 Au s + Zn CN 4 2 -
Correct answer
B. 2 Al 2 O 3 + 3 C → 4 Al + 3 CO 2
Step-by-step solution
The Hall–Héroult process is the major industrial process for smelting aluminium. It involves dissolving aluminium oxide (alumina) (obtained most often from bauxite, aluminium's chief ore, through the Bayer process) in molten cryolite, and electrolyzing the molten salt bath, typically in a purpose-built cell. In this process carbon electrodes are used. The following reactions take place 2 Al 2 O 3 + 3 C → 4 Al + 3 CO 2