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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.
∴ The spin-only magnetic moment is calculated by using the formula,
µ = `sqrt (n(n + 2))`
= `sqrt (3(3 + 2))`
= `sqrt 15`
= 3.87 B.M.
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