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Question
Write down the number of 3d electrons in the following ion:
Cu2+
Indicate how would you expect the five 3d orbitals to be occupied for this hydrated ion (octahedral).
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Solution 1
| Metal ion | Number of d-electrons | Filling of d-orbitals |
| Cu2+ | 9 | \[\ce{t^6_{2g}e^3_g}\] |
Solution 2
Cu2+: 3d9
Filling of orbitals in an octahedral hydrated ion:
Cu2+: \[\ce{t^6_{2g}e^3_g}\]
| ↑↓ | ↑ | eg | |
| ↑↓ | ↑↓ | ↑↓ | t2g |
(1 unpaired electron)
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