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Question
Calculate the ‘spin only’ magnetic moment of \[\ce{M^{2+}_{ (aq)}}\] ion (Z = 27).
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Solution
The electronic configuration of the M atom (Z = 27) is [Ar] 3d7 4s2.
∴ Electronic configuration of M2+ = [Ar] 3d7
i.e.,
| ↑↓ | ↑↓ | ↑ | ↑ | ↑ |
So it has three unpaired electrons.
∴ 'Spin-only' magnetic moment is calculated by using formula,
(µ) = `sqrt("n"("n" + 2))` B.M.
= `sqrt(3(3 + 2))` B.M.
= `sqrt15` B.M.
= 3.87 B.M.
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