For particles having same kinetic energy, the de Broglie wavelength is-

1. Directly proportional to its velocity

2. Inversely proportional to its velocity

3. Independent of velocity and mass

4. Unpredictable

Subtopic:  De Broglie Equation |
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Photochemical dissociation of oxygen results in the production of two oxygen atoms, one in the ground state and one in the excited state.

O2 hv O→O*

The maximum wavelength () needed for this is 174 nm. If the excitation energy O→O* is 3.15 x 10-19 J. How much energy in kJ mole-1 is needed for the dissociation of one mole of oxygen into normal atoms in ground state?

1. 498.3 kJ mol-1

2. 418.3 kJ mol-1

3. 524.1 kJ mol-1

4. 612.8 kJ mol-1

Subtopic:  Bohr's Theory |
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Rutherford's scattering experiment is related to the size of the-

1. Nucleus

2. Atom

3. Electron

4. Neutron

Subtopic:  Introduction of Atomic Structure |
 81%
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The  energy needed to convert helium atom  to He +2 is -79eV. The first ionization energy of this atom is about 

1. 65.4eV

2. 51.8eV

3. 24.6eV

4. 27.2eV

Subtopic:  Bohr's Theory |
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Elements upto atomic number 103 have been synthesized and studied. If a newly discovered element is found to have an atomic number 106, its electronic configuration will be -

1. [Rn] 5f14, 6d4, 7s2

2. [Rn] 5f14, 6d1, 7s2 7p3

3. [Rn] 5f14, 6d, 7s0

4. [Rn] 5f14, 6d5, 7s1

Subtopic:  AUFBAU Principle |
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The most probable radius (in pm) for finding the electron in He+ is -

1. 0

2. 52.9

3. 26.5

4. 105.8

Subtopic:  Bohr's Theory |
 57%
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The mass ratio of photons corresponding to the first lines of the Lymann and the Balmer series of the atomic spectrum of hydrogen is :

1. 5 : 27 2. 1 : 4
3. 27 : 5 4. 4 : 1
Subtopic:  Hydrogen Spectra |
 56%
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An electron, practically at rest, is initially accelerated through a potential difference of 100 volts. It then has a de Broglie wavelength=λ1Å. It then get retarded through 19 volts and then it has wavelength λ2 Å. A further retardation through 32 volts changes the wavelength to λ3.

What is (λ3-λ2)/λ1?

1. 20/41

2. 10/63

3. 20/63

4. 10/41

Subtopic:  De Broglie Equation |
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Which of the following has the maximum number of  unpaired electons-

1. Mg2+

2. Ti3+

3. V3+

4. Fe2+

Subtopic:  Number of Electron, Proton & Neutron |
 71%
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There are three energy levels in an atom. How many spectral lines are possible in its emission spectra?

1. One

2. Two

3. Three

4. Four

Subtopic:  Type of Spectra |
 75%

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