Chemistry
During the electrolysis of molten lead bromide, which of the following takes place ?
- Bromine is released at the cathode
- Lead is deposited at the anode
- Bromine ions gain electrons
- Lead is deposited at the cathode
Electrolysis
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Answer
Lead is deposited at the cathode
Reason — The positive lead ions ( Pb2+) migrate towards the cathode when the current is turned on. They take 2 electrons each and become neutral lead atoms.
Reaction at cathode : Pb2+ + 2e- ⟶ Pb
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