1. 29 Atoms and Molecules
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7. Spectroscopy
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8. Continuous Spectra and Blackbody Radiation
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9. Discrete Spectra of the Elements
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10. The Hydrogen Spectrum
Wavelengths of visible lines in the hydrogen spectrum
Balmer’s formula
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11. Rutherford’s Experiment
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12. Using the Nuclear Model
Ionization
The nucleus
Isotopes
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13. Bohr’s Model of Atomic Quantization
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14. Bohr’s Model of Atomic Quantization (cont’d)
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15. Frequencies of Photons Emitted in Electron Transitions
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16. Representing Atomic States
Energy-level diagram
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17. The Bohr Hydrogen Atom
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18. Energy-Level Diagram of the Hydrogen Atom
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19. The Quantum-Mechanical Hydrogen Atom
Schrödinger found that the energy of the hydrogen atom is given by the same expression found by Bohr, or
The integer n is called the principal quantum number.
The angular momentum L of the electron’s orbit must be one of the values
The integer l is called the orbital quantum number.
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20. The Quantum-Mechanical Hydrogen Atom
The plane of the electron’s orbit can be tilted, but only at certain discrete angles. Each allowed angle is characterized by a quantum number m, which must be one of the values
The integer m is called the magnetic quantum number because it becomes important when the atom is placed in a magnetic field.
The electron’s spin can point only up or down. These two orientations are described by the spin quantum number ms, which must be one of the values
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21. Energy Levels in Multielectron Atoms
Hydrogen atom
Multielectron atom
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22. Excited States and the Pauli Exclusion Principle
Helium atom
Lithium atom
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23. The Periodic Table
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24. Building Up the Periodic Table
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25. Excitation by Absorption and Collision
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26. Emission Spectra
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27. Molecules
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28. Fluorescence
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29. Stimulated Emission and Lasers
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30. Photon Amplification
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31. A Helium-Neon Laser
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32. Reading Quiz What is the “Balmer formula” a formula for?
Masses of atomic nuclei of hydrogen isotopes
Wavelengths in the hydrogen emission spectrum
Energies of stationary states of hydrogen
Probabilities of electron position in stationary states of hydrogen
Answer: B
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33. Answer What is the “Balmer formula” a formula for?
Masses of atomic nuclei of hydrogen isotopes
Wavelengths in the hydrogen emission spectrum
Energies of stationary states of hydrogen
Probabilities of electron position in stationary states of hydrogen
Answer: B
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34. Reading Quiz
Which of the following aspects of the stationary states of hydrogen does Bohr’s analysis of the hydrogen atom get right?
The existence of a “spin” quantum number
The existence of a “magnetic” quantum number
The shapes of the electron clouds
The energies of the stationary states
Answer: D
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35. Answer
Which of the following aspects of the stationary states of hydrogen does Bohr’s analysis of the hydrogen atom get right?
The existence of a “spin” quantum number
The existence of a “magnetic” quantum number
The shapes of the electron clouds
The energies of the stationary states
Answer: D
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36. Checking Understanding
Suppose that an atomic excited state decays to the ground state by emission of two photons, with energies E1 and E2. Is it possible for that excited state to decay to the ground state by emission of a single photon with energy E1 + E2?
It is always possible, for every atom.
It is never possible, for any atom.
It is always possible for hydrogen atoms, but is unlikely for other atoms.
Answer: C
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37. Answer
Suppose that an atomic excited state decays to the ground state by emission of two photons, with energies E1 and E2. Is it possible for that excited state to decay to the ground state by emission of a single photon with energy E1 + E2?
It is always possible, for every atom.
It is never possible, for any atom.
It is always possible for hydrogen atoms, but is unlikely for other atoms.
Answer: C
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38. Checking Understanding
Which of the following is not a possible fluorescence process?
Absorption of red light and emission of green light
Absorption of ultraviolet light and emission of infrared light
Absorption of ultraviolet light and emission of green light
Absorption of blue light and emission of red light
Answer: A
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39. Answer Which of the following is not a possible fluorescence process?
Absorption of red light and emission of green light
Absorption of ultraviolet light and emission of infrared light
Absorption of ultraviolet light and emission of green light
Absorption of blue light and emission of red light
Answer: A
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