Chemistry - Metallurgy Question with Solution | TestHub

(A) Electrochemical extraction of Aluminum from bauxite done below $2500^{\circ }\mathrm{C}$

(B) $2\mathrm{Na}\left[\mathrm{Al}(\mathrm{OH}{)}_4\right]$ (aq.) $+2{\mathrm{CO}}_2(\mathrm{g}){\mathrm{Al}}_2{\mathrm{O}}_3\cdot 3{\mathrm{H}}_2\mathrm{O}(\mathrm{s})+2{\mathrm{NaHCO}}_3$ (aq.) The sodium aluminate present in solution is neutralised by passing ${\mathrm{CO}}_2$ gas and hydrated ${\mathrm{Al}}_2{\mathrm{O}}_3$ is precipitated.

(C) ${\mathrm{Al}}_2{\mathrm{O}}_3(\mathrm{s})+2\mathrm{NaOH}($ aq. $)+3{\mathrm{H}}_2\mathrm{O}(\mathrm{l})2\mathrm{Na}\left[\mathrm{Al}(\mathrm{OH}{)}_4\right]$ aq. Concentration of bauxite is carried out by heating the powdered ore with hot concentrated solution of NaOH

(D) In metallurgy of aluminum, ${\mathrm{Al}}_2{\mathrm{O}}_3$ is mixed with ${\mathrm{Na}}_3{\mathrm{AlF}}_6$