Cryolite is used in the electrolytic extraction of aluminium

Question

Cryolite is used in the electrolytic extraction of aluminium (A) to obtain more aluminium (B) to decompose bauxite (C) to protect anodes (D) as a reducing agent

Tardigrade Admin · Accepted Answer

Cryolite is used in the electrolytic extraction of aluminium to decompose bauxite.

cryolite N a_{3} A l_{6} ⇌ 3 N a F + A l F_{3} A l F_{3} ⇌ A l^{3 +} + 3 F^{-}

At cathode

A l^{3 +} + 3 e^{-} \to A l (l)

At anode

2 A l_{2} O_{3} + 12 F^{-} \to 4 A l F_{3} + 6 O^{2 -}

C (s) + (melt) O^{2 -} \to CO (g) + 2 e^{-}

C (s) + (melt) 2 O^{2 -} \to C O_{2} (g) + 4 e^{-}

Q. Cryolite is used in the electrolytic extraction of aluminium

to obtain more aluminium

to decompose bauxite

to protect anodes

as a reducing agent

Cryolite is used in the electrolytic extraction of aluminium to decompose bauxite. cryolite Na3​Al6​​⇌3NaF+AlF3​AlF3​⇌Al3++3F− At cathode Al3++3e−→Al(l) At anode 2Al2​O3​+12F−→4AlF3​+6O2− C(s)+( melt )O2−​→CO(g)+2e− C(s)+( melt )2O2−​→CO2​(g)+4e−