Easy MCQ +4 / -1 PYQ · JEE Mains 2020

The correct electronic configuration and spin-only
magnetic moment (BM) of Gd3+ (Z = 64), respectively, are :

  1. A [Xe]5f<sup>7</sup> and 8.9
  2. B [Xe]4f<sup>7</sup> and 7.9 Correct answer
  3. C [Xe]5f<sup>7</sup> and 7.9
  4. D [Xe]4f<sup>7</sup> and 8.9

Solution

Gd<sup>3+</sup> (Z = 64) = [Xe] 4f<sup>7</sup> <br><br>Magnetic moment ($\mu$) = $\sqrt {n\left( {n + 2} \right)}$ B.M <br><br>= $\sqrt {7\left( {7 + 2} \right)}$ <br><br>= 7.9 B.M

About this question

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

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