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The frequency radiation emitted when the electron falls from n=4 to n=1 in a hydrogen atom will be (Given ionization energy of H=2.18 × 10^-18 ~J…

NEET UG 2004 — Chemistry Physical Chemistry

2004mcqmedium

The frequency radiation emitted when the electron falls from n=4\mathrm{n}=4n=4 to n=1n=1n=1 in a hydrogen atom will be (Given ionization energy of H=2.18×10−18 Jatom−1\mathrm{H}=2.18 \times 10^{-18} \mathrm{~J} \mathrm{atom}^{-1}H=2.18×10−18 Jatom−1 and hhh =6.625×10−34Js)\left.=6.625 \times 10^{-34} \mathrm{Js}\right)=6.625×10−34Js) :

Official previous-year question

Held on 30 Apr 2004 · Verified 9 Jul 2026.

Options

  1. A

    1.54×1015 s−11.54 \times 10^{15} \mathrm{~s}^{-1}1.54×1015 s−1

  2. B

    1.03×1015 s−11.03 \times 10^{15} \mathrm{~s}^{-1}1.03×1015 s−1

  3. C

    3.08×1015 s−13.08 \times 10^{15} \mathrm{~s}^{-1}3.08×1015 s−1

  4. D

    2.00×1015 s−12.00 \times 10^{15} \mathrm{~s}^{-1}2.00×1015 s−1

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