For a metal ion, the calculated magnetic moment is 4.90 BM. This metal ion has ______ number of unpaired electrons.
Correct Answer: 4
Solution and Explanation
The magnetic moment of a complex is 4.9 B.M. Thus, unpaired electrons maybe 4. The expression for the magnetic moment is μ= \(\sqrt{n(n+2)}\)
Substitute values in the above expression.
4.9= \(\sqrt{n(n+2)}\)
24.01=n(n+2)
⇒ n=4.
So, the correct answer is 4.
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D and F Block Elements
The d-block elements are placed in groups 3-12 and F-block elements with 4f and 5f orbital filled progressively. The general electronic configuration of d block elements and f- block elements are (n-1) d 1-10 ns 1-2 and (n-2) f 1-14 (n-1) d1 ns2 respectively. They are commonly known as transition elements because they exhibit multiple oxidation states because of the d-d transition which is possible by the availability of vacant d orbitals in these elements.
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