JEE Main 2021ChemistryStructure of AtomEasyNumerical

JEE Main 2021 — Structure of Atom Question with Solution

JEE Main 2021 (25 Feb Shift 2)

Question

Electromagnetic radiation of wavelength 663 nm is just sufficient to ionise the atom of metal A. The ionization energy of metal A in kJ mol-1 is ___. (Rounded-off to the nearest integer) h=6.63×10-34Js,c=3.00×108 ms-1, NA=6.02×1023 mol-1

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Show full solutionCorrect answer: 181
Correct answer
181

Step-by-step explanation

E=hcλ×NA1000

=6.63×10-34×3×108×6.02×1023663×10-9×1000

=3×6.02×10 kJ

=180.6 kJ

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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.