Easy MCQ +4 / -1 PYQ · JEE Mains 2021

Identify the element for which electronic configuration in +3 oxidation state is [Ar]3d5 :

  1. A Ru
  2. B Mn
  3. C Co
  4. D Fe Correct answer

Solution

Mn(25) = [Ar]3d<sup>5</sup>4s<sup>2</sup> <br><br>Mn<sup>+3</sup> = [Ar]3d<sup>4</sup>4s<sup>0</sup> <br><br>Ru-belongs to 4d transition series <br><br>Co (27) = [Ar]3d<sup>7</sup>4s<sup>2</sup> <br><br>Co<sup>+3</sup> = [Ar]3d<sup>6</sup>4s<sup>0</sup> <br><br>Fe(26) = [Ar]3d<sup>6</sup>4s<sup>2</sup> <br><br>Fe<sup>+3</sup> = [Ar]3d<sup>5</sup>4s<sup>0</sup>

About this question

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

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