JEE Main 2021ChemistryClassification of Elements and Periodicity in PropertiesEasyMCQ

JEE Main 2021 — Classification of Elements and Periodicity in Properties Question with Solution

JEE Main 2021 (18 Mar Shift 1)

Question

The ionic radius of Na+ ions is 1.02A°. The ionic radii (in A°) of Mg2+ and Al3+, respectively, are

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Show full solutionCorrect option: B
Correct answer
B0.72 and 0.54

Step-by-step explanation

As we know nuclear charge increases, attraction of nucleus on electron increases because of that size decreases.

Here all ions have same number of electrons so as the number of protons increases nuclear charge increases and size decreases.

The ionic radii order is Na+>Mg2+>Al3+

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About this question

This is a previous-year question from JEE Main 2021, covering the Classification of Elements and Periodicity in Properties 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.