Question

Which of the following electronic configurations would be associated with the highest magnetic moment?

• A. \([Ar] 3d^7\)
• B. \([Ar] 3d^8\)
• C. \([Ar] 3d^2\)
• D. \([Ar] 3d^6\)

Answer 1

The Correct Option is D

To determine which electronic configuration is associated with the highest magnetic moment, we need to consider the number of unpaired electrons in each configuration. The magnetic moment is given by the formula:

\(\mu = \sqrt{n(n+2)} \, \text{BM}\) (Bohr Magneton) 

where \(n\) is the number of unpaired electrons.

1. \([Ar] \, 3d^7\):
   • This configuration has 3 unpaired electrons.
   • The magnetic moment is \(\mu = \sqrt{3(3+2)} = \sqrt{15} \, \text{BM}\).
2. \([Ar] \, 3d^8\):
   • This configuration has 2 unpaired electrons.
   • The magnetic moment is \(\mu = \sqrt{2(2+2)} = \sqrt{8} \, \text{BM}\).
3. \([Ar] \, 3d^2\):
   • This configuration has 2 unpaired electrons.
   • The magnetic moment is \(\mu = \sqrt{2(2+2)} = \sqrt{8} \, \text{BM}\).
4. \([Ar] \, 3d^6\):
   • This configuration has 4 unpaired electrons.
   • The magnetic moment is \(\mu = \sqrt{4(4+2)} = \sqrt{24} \, \text{BM}\).

Among the given configurations, \([Ar] \, 3d^6\) has the highest magnetic moment because it has the highest number of unpaired electrons, which is 4.

Therefore, the correct answer is \([Ar] \, 3d^6\).

Answer 2

The magnetic moment μ is given by:

μ=$\sqrt{n(n + 2)}$ BM

where n is the number of unpaired electrons. Among the options, [Ar] 3d⁶ has the highest number of unpaired electrons (4), leading to a maximum magnetic moment.