MCQ
$Cu(CN)_4^{2 - }$ is colourless as it absorbs light in
- AVisible region
- BUltraviolet region
- CInfrared region
- ✓All above are wrong
✓
Answer
Correct option: D.
All above are wrong
d
As the oxidation state of $Cu$ in the given compound is $Cu ^{+2}$, whose electronic cofiguration is $[ Ar ] 3 d ^9$.As we know that, only $d ^0$ and $d ^{10}$ configuration do not absorb light in visible region and rest absorb light in visible region.
As the oxidation state of $Cu$ in the given compound is $Cu ^{+2}$, whose electronic cofiguration is $[ Ar ] 3 d ^9$.As we know that, only $d ^0$ and $d ^{10}$ configuration do not absorb light in visible region and rest absorb light in visible region.
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