JEE Main 2025 · ChemistryNumerical answerNumerical valueMediumMulti-step

JEE Main 2 April 2025, Shift 2, Chemistry Q74

Question 74 of 75 in this shift, Chemistry question 24 of 25, Section B.

The spin-only magnetic moment value of

\mathrm{M^{n+}}

ion formed among Ni, Zn, Mn and Cu that has the least enthalpy of atomisation is __________. (in nearest integer) Here

n

is equal to the number of diamagnetic complexes among

\mathrm{K_2[NiCl_4]}

\mathrm{[Zn(H_2O)_6]Cl_2}

\mathrm{K_3[Mn(CN)_6]}

and

\mathrm{[Cu(PPh_3)_3I]}

Official answer

NTA final key.

Chapter: The d- and f-Block Elements
Topic: d-Block Elements
Idea tested: Enthalpy of Atomization

Same idea in other shifts

Asked 4× in all

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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.