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Question
The magnetic moment is associated with its spin angular momentum and orbital angular momentum. Spin only magnetic moment value of \[\ce{Cr^{3+}}\] ion is ______.
Options
2.87 B.M.
3.87 B.M.
3.47 B.M.
3.57 B.M.
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Solution
The magnetic moment is associated with its spin angular momentum and orbital angular momentum. Spin only magnetic moment value of \[\ce{Cr^{3+}}\] ion is 3.87 B.M..
Explanation:
\[\ce{Cr -> (Z = 24)}\]
\[\ce{Cr^{3+} -> (Z = 21)}\]
\[\ce{1s^2 2s^2 2P^6 3s^2 3p^6 3d^3 4s^0}\]
n = 3(3 unpaired electrons)
`mu = sqrt(n(n + 2))`
`mu = sqrt(3(3 + 2))`
`mu = sqrt(3(5))`
`mu = sqrt(15)` = 3.87 B.M.
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