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Cu^(2+) and Cd^(2+) are separated by fir...

`Cu^(2+)` and `Cd^(2+)` are separated by first adding KCN solution and then passing `H_(2)S` gas.
KCN reduces `Cu^(2+)` to `Cu^(+)` and forms a complex with it.

A

If both assertion and reason are true and the reason is the correct explanation of the assertion.

B

if both assertion and reason are true but reason is not the correct explanation of the assertion.

C

If assertion is true but reason is false.

D

If the assertion and reason both are false.

Text Solution

Verified by Experts

The correct Answer is:
B
The correct explanation of assertion is KCN form complex with `Cu^(+) and Cd^(2+)` and `K_(3)[Cu(CN)_(4)]` and `K_(2)[Cd(CN)_(4)]` respectively. On passing `H_(2)S` only `Cd^(2+)` complex gets decomposed to yellow CdS ppt.
Both assertion and reason are correct and reason is the correct explanation of assertion.
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