Bohr’s Model of Hydrogen Atom

IMPORTANT

Bohr’s Model of Hydrogen Atom: Overview

This topic covers concepts, such as Energy and Wavelength of Photon Emitted during De-excitation, Ionization Potential of Electron in H-atom, Number of Transitions from Nth State to Ground State, Angular Momentum in Nth Orbit, etc.

Important Questions on Bohr’s Model of Hydrogen Atom

EASY
IMPORTANT

The energy of the electron, the hydrogen atom, is known to be expressible in the form

E n = 13.6 eV n 2 ( n=1,2,3,.......... )

Use this expression, which of the following statement is/are true?

(i) Electron in the hydrogen atom cannot have energy of 2 eV.

(ii) Spacing between the lines (consecutive energy levels) within the given set of the observed hydrogen spectrum decreases as n increases.

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The ground state energy of the hydrogen atom is 13.6 eV . The kinetic and potential energies of electrons in this state are:

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Find the ratio of energies of photons produced due to the transition of an electron of a hydrogen atom from its
(i) second permitted energy level to the first level, and
(ii) the highest permitted energy level to the first permitted level.

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For a hydrogen atom the value of ionization energy is equal to:

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The ground state energy of the hydrogen atom is 13.6 eV. If the electron jumps to the ground state from the third excited state, the wavelength of the emitted photon is

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The ground state energy of hydrogen atom is -13.6 eV.

(i) What is the kinetic energy of an electron in the 2nd excited state?

(ii) If the electron jumps to the ground state from the 2nd excited state, calculate the wavelength of the spectral line emitted.

MEDIUM
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The frequency of radiation emitted when the electron falls from   n=4ton=1 in a hydrogen atom will be (Given ionization energy of   H=2.18× 10 18 Jato m 1 andh=6.625× 10 34 Js )

                                                                                                                                                                                                                               

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In hydrogen atom, energy of first excited state is   3.4eV . Find out KE of the same orbit of Hydrogen atom

                                                                                                                                                                                                                               

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According to Bohr’s theory the energy required for an electron in the   L i 2+  ion to be emitted from n = 2 state is (given that the ground state ionization energy of hydrogen atom is 13.6 eV)

                                                                                                                                                                                                                               

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The recoil speed of a hydrogen atom after it emits a photon in going from n=5 state to n=1 state is

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The Bohr radius of the fifth electron of the phosphorous atom (atomic number=15) acting as a dopant in silicon (relative dielectric constant=12) is

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The Bohr radius of the fifth electron of phosphorous atom (atomic number=15) acting as a dopant in silicon (relative dielectric constant=12) is ___________ Å

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The maximum wavelength of a photon which will ionize hydrogen atom is

plank's constant  =6.634×10-34 J s

Charge of electron=1.6×10-19 C

Speed of light=3×108 m s-1

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An electron in Bohr model of hydrogen atom absorbs a photon and gets excited to a state in which its angular momentum increases by hπ. Among the following, what may be the final energy of such an electron?

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The circumference of the innermost orbit of a single electron Bohr atom is 3.33  (Angstroms). The de Broglie wavelength of an electron in the n=4 orbit of hydrogen atom is

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If the mass of the electron were 10 times smaller, but the mass of the proton remained the same, then the radius of the first Bohr orbit in a hydrogen like atom would be

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The longest wavelength of the Lyman series of the hydrogen atom spectrum is λ. Which of the following wavelengths also belong to the Lyman series?

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The de-Broglie wavelength of the electron in the first Bohr orbit of the Hydrogen atom is equal to ( aB denotes the Bohr radius)

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If we consider the electron (charge =e, mass=m ) in the first Bohr orbit of a hydrogen atom as a small loop of current, then the magnitude of the magnetic dipole moment due to this current is

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The ratio of the speed of the electron in the first Bohr orbit (1s) of a hydrogen atom to that of the speed of light is approximately