JEE Main 2024ChemistryStructure of AtomHardNumerical

JEE Main 2024 — Structure of Atom Question with Solution

JEE Main 2024 (27 Jan Shift 2)

Question

Total number of ions from the following with noble gas configuration is

Sr2+(Z=38),Cs+(Z=55),La2+(Z=57)Pb2+(Z=82),Yb2+(Z=70) and Fe2+(Z=26)

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Show full solutionCorrect answer: 2
Correct answer
2

Step-by-step explanation

Noble gas configuration= ns2np6

38Sr2+=[36Kr]

Cs+=[54Xe]

Yb702+=[54Xe]4f14

57La2+=[54Xe]5 d1

82Pb2+=[54Xe]4f145 d106 s2

26Fe2+=[18Ar]3d6

Cs+ and  Sr2+ have noble gas configuration, which are Xe  and Kr, respectively.

Hence, the answer is 2.

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About this question

This is a previous-year question from JEE Main 2024, covering the Structure of Atom 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.