1. Chapter 38

2. The work function of metal A is 3. 0 eV
The work function of metal A is 3.0 eV. Metals B and C have work functions of 4.0 eV and 5.0 eV, respectively. Ultraviolet light shines on all three metals, creating photoelectrons. Rank in order, from largest to smallest, the stopping voltages for A, B, and C.
1. VA > VB > VC
2. VC > VB > VA
3. VA = VB = VC
STT38.1

3. The work function of metal A is 3. 0 eV
The work function of metal A is 3.0 eV. Metals B and C have work functions of 4.0 eV and 5.0 eV, respectively. Ultraviolet light shines on all three metals, creating photoelectrons. Rank in order, from largest to smallest, the stopping voltages for A, B, and C.
1. VA > VB > VC
2. VC > VB > VA
3. VA = VB = VC
STT38.1

4. 1. The photons travel faster. 2. Each photon has more energy.
The intensity of a beam of light is increased but the light’s frequency is unchanged. Which of the following is true?
1. The photons travel faster.
2. Each photon has more energy.
3. There are more photons per second.
4. The photons are larger.
STT38.2

5. 1. The photons travel faster. 2. Each photon has more energy.
The intensity of a beam of light is increased but the light’s frequency is unchanged. Which of the following is true?
1. The photons travel faster.
2. Each photon has more energy.
3. There are more photons per second.
4. The photons are larger.
STT38.2

6. What is the quantum number of this particle confined in a box?
STT38.3

7. What is the quantum number of this particle confined in a box?
STT38.3

8. A photon with a wavelength of 414 nm has energy Ephoton = 3. 0 eV
A photon with a wavelength of 414 nm has energy Ephoton = 3.0 eV. Do you expect to see a spectral line with = 414 nm in the emission spectrum of the atom represented by this energy-level diagram? If so, what transition or transitions will emit it?
STT38.4part1

9. A photon with a wavelength of 414 nm has energy Ephoton = 3. 0 eV
A photon with a wavelength of 414 nm has energy Ephoton = 3.0 eV. Do you expect to see a spectral line with = 414 nm in the emission spectrum of the atom represented by this energy-level diagram? If so, what transition or transitions will emit it?
STT38.4part1

10. A photon with a wavelength of 414 nm has energy Ephoton = 3. 0 eV
A photon with a wavelength of 414 nm has energy Ephoton = 3.0 eV. Do you expect to see a spectral line with λ = 414 nm in the absorption spectrum of the atom represented by this energy-level diagram? If so, what transition or transitions will absorb it?
STT38.4part2

11. A photon with a wavelength of 414 nm has energy Ephoton = 3. 0 eV
A photon with a wavelength of 414 nm has energy Ephoton = 3.0 eV. Do you expect to see a spectral line with λ = 414 nm in the absorption spectrum of the atom represented by this energy-level diagram? If so, what transition or transitions will absorb it?
STT38.4part2

12. What is the quantum number of this hydrogen atom?
STT38.5

13. What is the quantum number of this hydrogen atom?
STT38.5

14. Chapter 38
Reading Quiz

15. Who first postulated the idea of light quanta?
1. Planck
2. Bohr
3. De Broglie
4. Einstein
5. Heisenberg
IG38.1

16. Who first postulated the idea of light quanta?
1. Planck
2. Bohr
3. De Broglie
4. Einstein
5. Heisenberg
IG38.1

17. Cite one experiment that confirms the de Broglie hypothesis.
1. Spectrum of blackbody radiation
2. X-ray penetration depth
3. Electron diffraction
4. Optical pumping
5. Nuclear magnetic resonance
IG38.2

18. Cite one experiment that confirms the de Broglie hypothesis.
1. Spectrum of blackbody radiation
2. X-ray penetration depth
3. Electron diffraction
4. Optical pumping
5. Nuclear magnetic resonance
IG38.2

19. 4. Atomic orbital diagram 5. Feynman diagram
What is the name of the diagram used to represent the stationary states of an atom?
Atomic-state diagram
Energy-level diagram
3. Standing wave diagram
4. Atomic orbital diagram
5. Feynman diagram
IG38.4

20. 4. Atomic orbital diagram 5. Feynman diagram
What is the name of the diagram used to represent the stationary states of an atom?
1. Atomic-state diagram
2. Energy-level diagram
3. Standing wave diagram
4. Atomic orbital diagram
5. Feynman diagram
IG38.4

21. 1. less then the threshold frequency.
In the photoelectric effect experiment, current flows when the light frequency is
1. less then the threshold frequency.
2. equal to the threshold frequency.
3. greater then the threshold frequency.
4. less than the cathode’s work function.
5. equal to the cathode’s work function.
IG38.5

22. 1. less then the threshold frequency.
In the photoelectric effect experiment, current flows when the light frequency is
1. less then the threshold frequency.
2. equal to the threshold frequency.
3. greater then the threshold frequency.
4. less than the cathode’s work function.
5. equal to the cathode’s work function.
IG38.5

23. The minimum amount of energy needed to free an electron from a piece of metal is called the
1. Gibb’s free energy.
2. quantum energy.
3. liberation potential.
4. threshold energy.
5. work function.
IG38.6

24. The minimum amount of energy needed to free an electron from a piece of metal is called the
1. Gibb’s free energy.
2. quantum energy.
3. liberation potential.
4. threshold energy.
5. work function.
IG38.6

25. The Bohr model successfully explained the spectrum of
1. hydrogen.
2. helium.
3. hydrogen and helium.
4. all the naturally occurring elements.
5. all the elements in the periodic table.
IG38.7

26. The Bohr model successfully explained the spectrum of
1. hydrogen.
2. helium.
3. hydrogen and helium.
4. all the naturally occurring elements.
5. all the elements in the periodic table.
IG38.7