MCQ
A compound which liberates reddish brown gas around the anode during electrolysis in its molten state is-
- ASodium chloride.
- BCopper (II) oxide.
- CCopper (II) sulphate.
- DLead (II) bromide.
✓
Answer
- Lead (II) bromide.
Explanation:
We know that Bromine gas is reddish brown in colour and which can only liberates during electrolysis of Lead (II) bromide (PbBr2) During electrolysis of Lead (II) bromide , Positive lead ions (cations) move to the cathode and gain electrons to become lead metal and negative bromide ions (anions) move to the anode and loose an electron to make chlorine atoms. Two bromine atoms then combine and the diatomic bromine gas (Br2) is released at the anode.
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