JEE Main 2021ChemistryCoordination CompoundsWarners Theory And Valence Bond TheorymediumNumerical

JEE Main 2021 — Coordination Compounds Question with Solution

From: JEE Main 2021 (Online) 20th July Evening Shift

Question

An aqueous solution of NiCl2 was heated with excess sodium cyanide in presence of strong oxidizing agent to form [Ni(CN)6]2. The total change in number of unpaired electrons on metal centre is _______________.

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Show full solutionCorrect answer: 2
Correct answer
2

Step-by-step explanation

[Ni(CN)6]2-

Ni+4 d6, CN- strong field ligand. So pairing will happen.

JEE Main 2021 (Online) 20th July Evening Shift Chemistry - Coordination Compounds Question 191 English Explanation 1

Here zero unpaired electron

NiCl2 Ni2+ d8

JEE Main 2021 (Online) 20th July Evening Shift Chemistry - Coordination Compounds Question 191 English Explanation 2Cl- Weak field ligand. two unpaired e-

Change = 2.

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About this question

This is a previous-year question from JEE Main 2021, covering the Coordination Compounds 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.