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Karnataka Board PUCPUC Science Class 11

A Hydrogen Atom in Ground State Absorbs 10.2 Ev of Energy. the Orbital Angular Momentum of the Electron is Increased by

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Question

A hydrogen atom in ground state absorbs 10.2 eV of energy. The orbital angular momentum of the electron is increased by

Options

  • 1.05 × 10−34 J s

  • 2.11 × 10−34 J s

  •  3.16 × 10−34 J s

  • 4.22 × 10−34 J s

MCQ
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Solution

 1.05 × 10−34 J s

Let after absorption of energy, the hydrogen atom goes to the nth excited state.

Therefore, the energy absorbed can be written as

`10.2 = 13.6 xx (1/1^2 - 1/n^2)`

⇒ `10.2/13.6 = 1- 1/n^2`

`rArr = 1/(n^2) = (13.6 - 10.2)/13.6`

`rArr = 1/n^2 = 3.4/13.6`

`rArr n^2 = 4`

`rArr n = 2`

The orbital angular momentum of the electron in the nth state is given by

`L_n =(nh)/(2pi)`

Change in the angular momentum,

`DeltaL = (2h)/(2pi) - h/(2pi) = h/(2pi)`

`DeltaL = 1.05xx10^-34` Js

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Chapter 43: Bohr’s Model and Physics of Atom - MCQ [Page 383]

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HC Verma Concepts of Physics Volume 1 and 2 [English]
Chapter 43 Bohr’s Model and Physics of Atom
MCQ | Q 11 | Page 383

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