JEE Main 2021ChemistryStructure Of AtomPhotoelectric EffectmediumNumerical

JEE Main 2021Structure Of Atom Question with Solution

From: JEE Main 2021 (Online) 25th February Evening Shift

Question

Electromagnetic radiation of wavelength 663 nm is just sufficient to ionise the atom of metal A. The ionization enegy of metal A in kJ mol1 is __________. (Rounded off to the nearest integer)

[h = 6.63 1034 Js, c = 3.00 108 ms1, NA = 6.02 1023 mol1]

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Show full solutionCorrect answer: 180.6
Correct answer
180.6

Step-by-step explanation

Energy of EMR = IE of the metal (A)

atom1 mol1

J mol1 [ = 663 nm = 663 109 m]

= 180600 J mol1 = 180.6 kJ mol1 181 kJ mol1

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About this question

This is a previous-year question from JEE Main 2021, 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.