Easy INTEGER +4 / -1 PYQ · JEE Mains 2021

The number of f electrons in the ground state electronic configuration of Np (Z = 93) is ___________. (Nearest integer)

Answer (integer) 18

Solution

Np = 1s<sup>2</sup> 2<sup>2</sup> 2p<sup>6</sup> 3s<sup>2</sup> 3p<sup>6</sup> 4s<sup>2</sup> 3d<sup>10</sup> 4p<sup>6</sup> 5s<sup>2</sup> 4d<sup>10</sup> 5p<sup>6</sup> 6s<sup>2</sup><br><br>4f<sup>14</sup> 5d<sup>10</sup> 6p<sup>6</sup> 7s<sup>2</sup> 5f<sup>4</sup> 6d<sup>1</sup><br><br>Total No. of 'f' electron = 14e<sup>$-$</sup> + 4e<sup>$-$</sup> = 18

About this question

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

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