Q. No.The frequency of microwaves with wavelength 4 x 107 nm is 7.5 x 109 s-1. The wavenumber of the microwave is:
1. 30 m-1
2. 25 m-1
3. 40 m-1
4. 35 m-1
1. 30 m-1
2. 25 m-1
3. 40 m-1
4. 35 m-1
Subtopic: Bohr's Theory |
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Bohr model can explain:
| 1. | The spectrum of hydrogen atom only |
| 2. | Spectrum of an atom or ion containing one electron only |
| 3. | The spectrum of hydrogen molecule |
| 4. | The solar spectrum |
Subtopic: Bohr's Theory |
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According to Bohr's theory, what is the angular momentum of an electron located in the fifth orbit?
1.
2.
3.
4.
Subtopic: Bohr's Theory |
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The radius of the second Bohr orbit for hydrogen atom is:
(Planck's Const. h = 6.6262 × 10–34 Js; mass of electron = 9.1091 × 10–31 kg; charge of electron e = 1.60210 ×10–19 C; permittivity of vaccum ∈0 = 8.854185 ×10–12 kg–1m–3A2)
1. 0.529 Å
2. 2.12 Å
3. 1.65 Å
4. 7.76 Å
Subtopic: Bohr's Theory |
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According to Bohr's model, how does the radius of the third orbit compare to the radius of the first orbit?
1. Equal to the radius of the first orbit
2. Three times the radius of the first orbit
3. Five times the radius of the first orbit
4. Nine times the radius of the first orbit
1. Equal to the radius of the first orbit
2. Three times the radius of the first orbit
3. Five times the radius of the first orbit
4. Nine times the radius of the first orbit
Subtopic: Bohr's Theory |
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The energy of an electron in the first Bohr orbit of H atom is –13.6 eV. The possible energy value (s) of the excited state(s) for electrons in Bohr orbits of hydrogen is (are):
1. –3.4 eV
2. –4.2 eV
3. –6.8 eV
4. +6.8 eV
Subtopic: Bohr's Theory |
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Bohr model can explain:
1. the solar spectrum
2. the spectrum of the hydrogen molecule
3. the spectrum of hydrogen atoms only
4. spectrum of an atom or ion containing one electron only
Subtopic: Bohr's Theory |
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The energy of an electron in the first Bohr orbit is −13.6 eV. Based on this information, it can be concluded that the energy of Be3+ in the first excited state will be:
1. − 30.6 eV
2. − 40.8 eV
3. − 54.4 eV
4. + 40.8 eV
1. − 30.6 eV
2. − 40.8 eV
3. − 54.4 eV
4. + 40.8 eV
Subtopic: Bohr's Theory |
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Consider the Bohr’s model of a one-electron atom where the electron moves around the nucleus. In the following, List-I contains some quantities for the nth orbit of the atom and List-II contains options showing how they depend on n:
Which of the following options has the correct combination considering List-I and List-II?
1. (I)-(T), (II)-(S) and (III)-(P)
2. (II)-(R), (I)-(U) and (IV)-(P)
3. (I)-(T), (II)-(P) and (IV)-(U)
4. (II)-(Q) and (III)-(T)
| List–I | List–II | ||
| (I) | Radius of the nth orbit | (P) | \(\propto \mathrm{n}^{-2}\) |
| (II) | Angular momentum of the electron in the nth orbit | (Q) | \(\propto \mathrm{n}^{-1}\) |
| (III) | Kinetic energy of the electron in the nth orbit | (R) | \(\propto \mathrm{n}^0\) |
| (IV) | Potential energy of the electron in the nth orbit | (S) | \(\propto \mathrm{n}^1\) |
| (T) | \(\propto \mathrm{n}^2\) | ||
| (U) | \(\propto \mathrm{n}^{1 / 2}\) |
1. (I)-(T), (II)-(S) and (III)-(P)
2. (II)-(R), (I)-(U) and (IV)-(P)
3. (I)-(T), (II)-(P) and (IV)-(U)
4. (II)-(Q) and (III)-(T)
Subtopic: Bohr's Theory |
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Given below are two statements:
In the light of the above statements, choose the correct answer from the option given below:
1. Both Statement I and Statement II are true.
2. Both Statement I and Statement II are false.
3. Statement I is true but Statement II is false.
4. Statement I is false but Statement II is true.
| Statement I: |  h\(\)v = (E2-E1) absorbs a photon. |
| Statement II: |  hv = (E2-E1) = emitted a photon. |
1. Both Statement I and Statement II are true.
2. Both Statement I and Statement II are false.
3. Statement I is true but Statement II is false.
4. Statement I is false but Statement II is true.
Subtopic: Bohr's Theory | Hydrogen Spectra |
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