JEE Main 2020Chemistryd and f Block ElementsEasyMCQ

JEE Main 2020d and f Block Elements Question with Solution

JEE Main 2020 (05 Sep Shift 1)

Question

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

Choose an option

Show full solutionCorrect option: B
Correct answer
B[Xe]4f7 and 7.9

Step-by-step explanation

Electronic configuration of

64Gd=[Xe]4F75d16s2

Gd3+64=[Xe]4F7

No. of unpaired electron =7

μ=n(n+2)BM

=63

=7.93 BM

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About this question

This is a previous-year question from JEE Main 2020, covering the d and f Block Elements chapter of Chemistry. PrepSharp catalogues every PYQ from JEE Main with a verified answer key and step-by-step solution prepared by IIT alumni — so you can search by chapter, topic or year and revise efficiently.