- What does the Lyman series in hydrogen correspond to?
A) Transitions to n=1
B) Transitions to n=2
C) Transitions to n=3
D) Transitions to n=4
Answer: A) Transitions to n=1.
Explanation: The Lyman series involves transitions to the ground state (n=1) and emits ultraviolet radiation.
- How does the energy of the emitted photon relate to the energy levels involved in the transition?
A) It is always the same regardless of the transition.
B) It equals the difference in energy between the two levels involved.
C) It is unrelated to the energy levels.
D) It depends on the atomic mass of the element.
Answer: B) It equals the difference in energy between the two levels involved.
Explanation: The energy of the emitted photon is directly related to the energy difference between the two quantum levels during the transition.
- What occurs when a photon is absorbed by an atom?
A) The electron drops to a lower energy level.
B) The atom becomes ionized.
C) The electron moves to a higher energy level.
D) The atom emits a photon.
Answer: C) The electron moves to a higher energy level.
Explanation: Absorption of a photon provides energy, allowing an electron to transition to a higher energy state.
- What is the significance of the zero energy level in the Bohr model?
A) It corresponds to the ground state.
B) It indicates ionization.
C) It is the maximum energy level.
D) It has no significance.
Answer: B) It indicates ionization.
Explanation: The zero energy level represents the point at which an electron is free from the nucleus, indicating complete ionization.
- Which type of radiation is produced when an electron transitions from n=3 to n=2 in hydrogen?
A) Infrared radiation
B) Ultraviolet radiation
C) Visible light
D) X-rays
Answer: C) Visible light.
Explanation: The transition from n=3 to n=2 falls within the visible spectrum and is part of the Balmer series.
- What property of light is demonstrated by the spectral lines of an atom?
A) Reflection
B) Refraction
C) Diffraction
D) Quantization
Answer: D) Quantization.
Explanation: The discrete spectral lines represent quantized energy levels within an atom, reflecting the specific energies associated with electron transitions.
- Which of the following best describes the Bohr model’s treatment of electrons?
A) As waves only.
B) As particles moving in fixed paths.
C) As a cloud of probabilities.
D) As continuous fields.
Answer: B) As particles moving in fixed paths.
Explanation: The Bohr model simplifies electron behavior by depicting them as particles in fixed, circular orbits around the nucleus.
- Which of the following series emits the shortest wavelengths in the hydrogen spectrum?
A) Lyman series
B) Balmer series
C) Paschen series
D) Brackett series
Answer: A) Lyman series.
Explanation: The Lyman series emits ultraviolet light, which has shorter wavelengths compared to the visible and infrared emissions of other series.
- Which of the following factors affects the ionization energy of an atom?
A) Atomic size
B) Nuclear charge
C) Electron shielding
D) All of the above
Answer: D) All of the above.
Explanation: Ionization energy is influenced by atomic size, nuclear charge, and the shielding effect of inner electrons.
- What happens to the spectral lines of an atom in a strong magnetic field?
A) They disappear.
B) They shift positions.
C) They become wider.
D) They remain unchanged.
Answer: B) They shift positions.
Explanation: In a strong magnetic field, the Zeeman effect causes spectral lines to split and shift in position due to interaction with the magnetic field.
Leave a comment