JEE Main 2021 · ChemistryMultiple choiceSingle correctMediumApplication

JEE Main 25 February 2021, Shift 1, Chemistry Q39

Question 39 of 90 in this shift, Chemistry question 9 of 30, Section A.

In which of the following pairs, the outer most electronic configuration will be the same ?

(1) $\mathrm{V^{2+}}$ and $\mathrm{Cr^{+}}$
(2) $\mathrm{Cr^{+}}$ and $\mathrm{Mn^{2+}}$ Official answer
(3) $\mathrm{Ni^{2+}}$ and $\mathrm{Cu^{+}}$
(4) $\mathrm{Fe^{2+}}$ and $\mathrm{Co^{+}}$

Official answer

Option 2

NTA final key.

Chapter: The d- and f-Block Elements
Topic: d-Block Elements
Idea tested: Electronic Configuration

Same idea in other shifts

Asked 4× in all

9 Apr 2024, Shift 2 · Q66The electronic configuration of Einsteinium is : (Given atomic number of Einsteinium = 99)MediumSingle correct
8 Apr 2023, Shift 1 · Q80In chromyl chloride, the number of d-electrons present on chromium is same as in (Given at no. of Ti : 22, V : 23, Cr : 24, Mn : 25, Fe :…EasySingle correct
29 Jun 2022, Shift 1 · Q66The electronic configuration of Pt (atomic number 78) is :MediumSingle correct

Question text from the official JEE Main paper published by NTA; answer from the final answer key. Chapter, topic and idea tags, difficulty and skill are Lumi’s. Lumi analyses 108 of the 174 JEE Main shifts held from 2017 to 2026.