Consider the following isolation//purification processes.
(I) Heating impure metal with `I_(2)` at `150 - 200^(@)C` and passing the resulting volatile iodide on hot tungsten filament at `1400^(@)C` to get the pure metal.
(II) Heating the sulphide ore in air until a part is converted to oxide and then further heating in the absence of air to let the oxide react with unchanged metal sulphide to get the metal.
(III) Electroysis of the molten electrolyte containing metal oxide and cryolite of fluorspar to obtain the metal.
The processes used for obtaining aluminium, titanium and lead are respectively:

Options

A. `(I),(II)` and `(III)`
B. `(II),(III)` and `(I)`
C. `(III),(I)`and `(II)`
D. `(II),(I)`and `(III)`

Answer

C

Explanation

(I) `Ti(s)("impure") + 2I_(2)(g) overset(50-250^(@)C)rarrTiI_(4) ("volatile")`
`overset(1400^(@)C)underset("Tunghten filament")rarrTi(s)("pure") +2I_(2)(g)`
(II) `2PbS +3O_(2) overset(Delta)rarr2PbO + 2SO_(2)`
`PbS +2PbO overset("high")underset("temp")rarr 3Pb +SO_(2)`
(III) cathode: `A1_(3) ("melt") +3e^(-) rarr A1(1)`
Anode: `C(s) +O^(2-) ("melt")rarr CO(g) +2e^(-2)`
`C(s) +2O^(2-) ("melt") rarr CO_(2)(g) +4e^(-)`