JEE Main 2020ChemistryStructure of AtomEasyMCQ

JEE Main 2020 — Structure of Atom Question with Solution

JEE Main 2020 (05 Sep Shift 1)

Question

The difference between the radii of 3rd and 4th  orbits of Li2+ is ΔR1. The difference between the radii of 3rd and 4th  orbits of He+ ΔR2. Ratio ΔR1:ΔR2 is :

Choose an option

Show full solutionCorrect option: C
Correct answer
C2: 3

Step-by-step explanation

r=0.529n27A

For Li2+

rL2+n=4-rL2+n=3=0.5293[16-9]=ΔR1

For He+

rHe+n=4-rHe+n=3=0.5292[16-9]=ΔR2

ΔR1ΔR2=23

 

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About this question

This is a previous-year question from JEE Main 2020, 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.