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Which of the following statements is cor...

Which of the following statements is correct ?
(i) Copper is extracted by hydrometallury from low grade ores.
(ii) In electrolytic reduction of alumina , graphite is acting as anode and steel vessel with lining of carbon acts as cathode.
(iii) In Hall-Heroult process, aluminium is obtained at anode and CO and `CO_(2)` are produce at cathode

A

(i) only

B

(i) and (ii) only

C

(ii) and (iii) only

D

All of these

Text Solution

Verified by Experts

The correct Answer is:
B
In Hall-Heroult process,
At cathode : `Al_("(melt)")^(3+)+ 3e^(-) to Al_((l))`
At anode : `C_((s)) + O_("(melt)")^(2-) to CO_(2(g)) + 4e^(-)`
`C_((s)) + 2O_("(melt)")^(2-) to CO_(2(g)) + 4e^(-)`
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