The energy of electron orbiting in the n th orbit of hydrogen atom is given by the expression E n = - 13 . 6 n 2 e V . Calculate energy liberated when the electron jumps from the second to the first orbit.

Given. The energy of electron in n th orbit = E n = - 13 . 6 n 2 e V The energy liberated, when an electron jumps from one orbit to another is equal to the energy difference between these orbits. Therefe the energy liberated when an electron makes transition between second to first orbit is given by E = - 13 . 6 1 1 2 - 1 2 2 = - 13 . 6 1 1 - 1 4 = 10 . 2 eV

The energy of electron orbiting in the n th orbit of hydrogen atom is given by the expression E n = - 13 . 6 n 2 e V . Calculate wavelength of light emittedwhen an electron jumps from second to first orbit.

Given. The energy of electron in n th orbit = E n = - 13 . 6 n 2 e V The energy liberated, when an electron jumps from one orbit to another is equal to the energy difference between these orbits. Therefore, when an electron makes transition between second to first orbit is given by E = - 13 . 6 1 1 2 - 1 2 2 = - 13 . 6 1 1 - 1 4 = 10 . 2 eV By using Plank's relation it is equal to wavelength given by, λ = hc E , where h =Planck's constant and c = velocity of light, Putting the values, we have, λ = 6 . 6 × 10 - 34 × 3 × 10 8 10 . 2 × 1 . 6 × 10 - 19 = 1213 × 10 - 10 m

The energy of electron orbiting in the n th orbit of hydrogen atom is given by the expression E n = - 13 . 6 n 2 e V . Calculate the ionisation energy of the atom.

Given the energy of a hydrogen atom is given by E n = - 13 . 6 n 2 e V , where n = orbit number. The ionisation energy of the atom is defined as the minimum energy required to remove the electrons from its ground state.i.e n = 1 . Therefore the ground state energy of a hydrogen atom is E g = - 13 . 3 eV If the same amount of energy is given to this atom its energy becomes zero. it means the electron will leave the atom and the atom becomes ionised. Putting this value, the ionisation energy of hydrogen atom is 13 . 6 eV

E M B I B E

ISC Physics Class 12, Part-2>Chapter 13 - Atom, Origin of Spectra : Bohr's Theory of Hydrogen Atom>QUESTIONS>Q 14

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12th ICSE

IMPORTANT

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The energy of an electron in the first Bohr orbit of hydrogen atom is $- 22 \times 10^{- 19} J$ . Calculate the frequency of the light emitted when the electron makes a transition from second orbit to first orbit.

Important Questions on Atom, Origin of Spectra : Bohr's Theory of Hydrogen Atom

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12th ICSE

IMPORTANT

ISC Physics Class 12, Part-2>Chapter 13 - Atom, Origin of Spectra : Bohr's Theory of Hydrogen Atom>QUESTIONS>Q 15

The energy of the lowest level of hydrogen atom is

- 13.6 eV

. Calculate the energy, frequency and wavelength of the photon emitted by transition from

n = 4

to

n = 2

.

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12th ICSE

IMPORTANT

ISC Physics Class 12, Part-2>Chapter 13 - Atom, Origin of Spectra : Bohr's Theory of Hydrogen Atom>QUESTIONS>Q 16

The ionisation-potential of hydrogen atom is

13.6 V

. Find out wavelength of

H_{β}

line of Balmer series.

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IMPORTANT

ISC Physics Class 12, Part-2>Chapter 13 - Atom, Origin of Spectra : Bohr's Theory of Hydrogen Atom>QUESTIONS>Q 16

The ionisation-potential of hydrogenatom is

13.6 V

. Find out shortest wavelength of Lyman series.

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12th ICSE

IMPORTANT

ISC Physics Class 12, Part-2>Chapter 13 - Atom, Origin of Spectra : Bohr's Theory of Hydrogen Atom>QUESTIONS>Q 17

Calculate the wavelength of the

H_{α}

line of hydrogen spectrum. The energy levels of hydrogen atom are given by the expression

E_{n} = - (\frac{13.6}{n^{2}}) eV

.

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12th ICSE

IMPORTANT

ISC Physics Class 12, Part-2>Chapter 13 - Atom, Origin of Spectra : Bohr's Theory of Hydrogen Atom>QUESTIONS>Q 18

The energy of electron orbiting in the

n

th orbit of hydrogen atom is given by the expression

E_{n} = - (\frac{13.6}{n^{2}}) e V

. Calculate energy liberated when the electron jumps from the second to the first orbit.

HARD

12th ICSE

IMPORTANT

ISC Physics Class 12, Part-2>Chapter 13 - Atom, Origin of Spectra : Bohr's Theory of Hydrogen Atom>QUESTIONS>Q 18

The energy of electron orbiting in the

n

th orbit of hydrogen atom is given by the expression

E_{n} = - (\frac{13.6}{n^{2}}) e V

. Calculate wavelength of light emittedwhen an electron jumps from second to first orbit.

HARD

12th ICSE

IMPORTANT

ISC Physics Class 12, Part-2>Chapter 13 - Atom, Origin of Spectra : Bohr's Theory of Hydrogen Atom>QUESTIONS>Q 18

The energy of electron orbiting in the

n

th orbit of hydrogen atom is given by the expression

E_{n} = - (\frac{13.6}{n^{2}}) e V

. Calculate the ionisation energy of the atom.

HARD

12th ICSE

IMPORTANT

ISC Physics Class 12, Part-2>Chapter 13 - Atom, Origin of Spectra : Bohr's Theory of Hydrogen Atom>QUESTIONS>Q 19

The energies of two energy-levels of hydrogen atom are

- 3.4 e V

and

- 1.5 e V

. If electron transition occurs from the higher to the lower level, how much energy will be emitted? What will be the wavelength of the emitted radiation?