Easy MCQ +4 / -1 PYQ · JEE Mains 2021

What is the spin-only magnetic moment value (BM) of a divalent metal ion with atomic number 25, in it's aqueous solution?

  1. A zero
  2. B 5.26
  3. C 5.0
  4. D 5.92 Correct answer

Solution

<sub>25</sub>Mn = [Ar]3d<sup>5</sup> 4s<sup>2</sup><br> Mn<sup>2+</sup> = [Ar]3d<sup>5</sup> 4s<sup>0</sup><br><br> No. of unpaired electron (n) = 5<br><br> $\mu = \sqrt {n\left( {n + 2} \right)} \,BM$<br><br> $= \sqrt {5 \times 7} {\rm{ }} = \sqrt {35} {\rm{ }} = {\rm{ }}5.92{\rm{ }}$ BM

About this question

Subject: Chemistry · Chapter: d and f Block Elements · Topic: Properties of Transition Metals

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