JEE Main 2024 · ChemistryNumerical answerNumerical valueMediumMulti-step

JEE Main 8 April 2024, Shift 1, Chemistry Q86

Question 86 of 90 in this shift, Chemistry question 26 of 30, Section B.

The 'spin only' magnetic moment value of

\mathrm{MO_4^{2-}}

is ____________ BM. (Where M is a metal having least metallic radii. among Sc, Ti, V, Cr, Mn and Zn). (Given atomic number: Sc = 21, Ti = 22, V = 23, Cr = 24, Mn = 25 and Zn = 30)

Official answer

NTA final key.

Chapter: The d- and f-Block Elements
Topic: d-Block Elements
Idea tested: Spin-only Magnetism

Same idea in other shifts

Asked 6× in all

2 Apr 2026, Shift 2 · Q74Number of paramagnetic ions among the following d- and f-block metal ions is __________.…MediumNumerical value
4 Apr 2026, Shift 2 · Q62Consider $|x|$ is the difference in oxidation states of Mn in highest manganese fluoride and highest manganese oxide. The ions with $|x|$ …MediumOther
3 Apr 2025, Shift 1 · Q62The metal ions that have the calculated spin-only magnetic moment value of 4.9 B.M. are : A. $\mathrm{Cr^{2+}}$ B. $\mathrm{Fe^{2+}}$ C.…EasyOther
8 Apr 2025, Shift 2 · Q58The correct decreasing order of spin only magnetic moment values (BM) of $\mathrm{Cu^+}$ , $\mathrm{Cu^{2+}}$ , $\mathrm{Cr^{2+}}$ and…EasySingle correct
6 Apr 2024, Shift 2 · Q86Among $\mathrm{VO_2^+}$ , $\mathrm{MnO_4^-}$ and $\mathrm{Cr_2O_7^{2-}}$ , the spin-only magnetic moment value of the species with least…MediumNumerical value

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 42 of the 174 JEE Main shifts held from 2017 to 2026.