What is the Q-value of the reaction? ¹H+⁷Li → ⁴He+⁴He The atomic masses of ¹H,⁴He and ⁷Li are 1.0078254u, 4.0026034u and 7.016004u, respectively.
Options
(a) 17.35 MeV (b) 18.06 MeV (c) 177.35 MeV […]
If the binding energy of the electron in a hydrogen atom is 13.6 eV, the energy required to remove the electron from the first excited state of Li⁺⁺ is
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(a) 122.4 eV […]
If 10000 V is applied across an X-ray tube, what will be the ratio of de-Broglie wavelength of the incident electrons to the shortest wavelength X-ray produced? (e/m for electron =1.8×10¹¹ C kg⁻¹)
Options […]
When the wave of hydrogen atom comes from infinity into the first orbit, the value of wave number is
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(a) 109700 cm⁻¹ (b) 1097 cm⁻¹ (c) 109 cm⁻¹ (d) None of these
Correct […]
The electron of a hydrogen atom revolves round the proton in a circular nth orbit of radius rn=ε₀n²h²/(πme²) with a speed vn=e²/2ε₀nh. The current due to the cirulating charge is proportional to
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Which of the following transitions will have highest emission wavelength?
Options
(a) n=2 to n=1 (b) n=1 to n=2 (c) n=2 to n=5 (d) n=5 to n=2
Correct Answer:
n=5 to n=2
Explanation: […]
The wavelength of first line of Balmer series is 6563Å. The wavelength of first line of Lyman series will be
Options
(a) 1215.4Å (b) 2500Å (c) 7500Å (d) 600Å
Correct Answer:
1215.4Å
Explanation:
λ(ʟyman) […]
The ratio of longest wavelength corresponding to Lyman and Blamer series in hydrogen spectrum is
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(a) 3 / 23 (b) 7 / 29 (c) 9 / 13 (d) 5 / 27
Correct […]
When alpha particles captures and electron, then it becomes a
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(a) helium atom (b) hydrogen atom (c) helim ion (d) hydrogen ion
Correct Answer:
helim ion
Explanation:
No explanation available. Be the […]
The wavelength of Kα line in copper is 1.5Å. The ionisation energy of K electron in copper is
Options
(a) 11.2×10⁻¹⁷ J (b) 12.9×10⁻¹⁶ J (c) 1.7×10⁻¹⁵ J (d) 10×10⁻¹⁶ J
Correct Answer:
12.9×10⁻¹⁶ […]
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