Chemistry - Metallurgy Question with Solution | TestHub

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

(B) $2\mathrm{Na}{\left[\mathrm{Al}(\mathrm{OH}{)}_4\right]}_{\text{(aq.) }}+2{\mathrm{CO}}_{2(\mathrm{g})}{\mathrm{Al}}_2{\mathrm{O}}_3\cdot 3{\mathrm{H}}_2{\mathrm{O}}_{(\mathrm{s})}+2{\mathrm{NaHCO}}_{3(\mathrm{aq}.)}$

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) ${\mathrm{Al}}_2{\mathrm{O}}_{3(\mathrm{s})}+2{\mathrm{NaOH}}_{(\mathrm{aq}.)}+3{\mathrm{H}}_2{\mathrm{O}}_{(\mathrm{l})}2\mathrm{Na}{\left[\mathrm{Al}(\mathrm{OH}{)}_4\right]}_{\text{aq. }}$.

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 ${\mathrm{Na}}_3{\mathrm{AlF}}_6$