JEE Main 2019ChemistryStructure Of AtomHydrogen SpectrumeasyMCQ

JEE Main 2019Structure Of Atom Question with Solution

From: JEE Main 2019 (Online) 11th January Morning Slot

Question

Heat treatment of muscular pain involves radiation of wavelength of about 900 nm. Which spectral line of H atom is suitable for this purpose?

[RH = 1 105 cm–1, h = 6.6 10–34 Js, c = 3 108 ms–1]

Choose an option

Show full solutionCorrect option: C
Correct answer
CPaschen, 3

Step-by-step explanation

Given, RH = 1 105 cm–1

= 10-5 cm

= 10-7 cm 100

= 100 nm

We know,



=

[For H atom Z = 1]



=

Given, = 900 nm

= 900



By checking each options you can see

when nL = 3 and nH = then



Option C is correct.

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About this question

This is a previous-year question from JEE Main 2019, 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.