JEE Main 2021ChemistryStructure Of AtomQuantum Mechanical Model Of AtommediumNumerical

JEE Main 2021Structure Of Atom Question with Solution

From: JEE Main 2021 (Online) 24th February Morning Shift

Question

A proton and a Li3+ nucleus are accelerated by the same potential. If and denote the de Broglie wavelengths of Li3+ and proton respectively, then the value of is x 10-1.
The value of x is ______. (Rounded off to the nearest integer)
[Mass of Li3+ = 8.3 mass of proton]

Enter your answer

Show full solutionCorrect answer: 2
Correct answer
2

Step-by-step explanation

Given, mass of Li3+ = 8.3 times of mass of proton formula,

De-Broglie wavelength,

Here, h = Planck's constant = 6.624 1034 J-s

m = Mass of atom

q = Charge (or number of electrons)

.... (i)

.... (ii)

Now, Eq. (i) divided by Eq. (ii), we get,



We know that mLi = 8.3 mp

= 2 101

Hence, x 101, x = 2

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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.