In Class Practice - Chapter 05
Name: ___________________________________________
Period: __________________________ Teacher: _________________________________________________________
5.1 Light and Quantized Energy
 Wave nature of light
Practice Problems
1. A helium-neon laser emits light with a wavelength of 633 nm. What is
the frequency of this light?
2. What is the wavelength of X rays having a frequency of
4.80x1017 Hz?
3. An FM radio station broadcasts at a frequency of 98.5 MHz. What is
the wavelength of the station’s broadcast signal?
 Particle nature of light
Practice Problems
4. Calculate the energy of a gamma ray photon whose frequency is
5.02x1020 Hz.
5. What is the difference in energy between a photon of violet light with
a frequency of 6.8x1014 Hz and a photon of red light with a frequency
of 4.3x1014 Hz?
6. Calculate the energy of a photon of ultraviolet light that has a
wavelength of 49.0 nm.
5.2 Quantum Theory and the Atom
 The Bohr atomic model
7. What feature of Bohr’s atomic model accounted for the fact that
electrons can have only certain energies?
8. Describe what is happening when an atom emits a photon.
9. How many electrons can the second principal energy level hold? How
many electrons can the third principal energy level hold? Explain the
difference in these numbers of electrons.
In Class Practice - Chapter 05
Name: ___________________________________________
Period: __________________________ Teacher: _________________________________________________________
5.3 Electron Configuration
 Writing electron configurations
Practice Problems
10. When writing the electron configuration of an atom, in what general
order are the sublevels written?
11. How is the number of electrons in an energy sublevel indicated in an
electron configuration?
12. Write the electron configurations of the following elements.
a. sulfur
b. calcium
c. bromine
d. magnesium
Practice Problems
13. Using noble-gas notation, write the electron configurations of the
following elements.
a. fluorine
b. phosphorus
c. calcium
d. cobalt
e. selenium
f. technetium
g. iodine
h. holmium
i. iridium
j. radium
 Valence electrons
Practice Problems
14. Write electron-dot structures for the following elements.
a. nitrogen
b. aluminum
c. neon
d. strontium
e. antimony
f. iodine
g. lead
h. cesium
15. What electron-dot structure is shared by all noble gases except
helium?
•
16. List three elements that have the electron-dot structure
• X •• .
•
In Class Practice - Chapter 05
Name: ___________________________________________
Period: __________________________ Teacher: _________________________________________________________
Chapter 5 Review
17. When light passes from air into a denser material, such as glass or
water, it slows down. How will the light’s wavelength change as it
slows down? Explain.
18. Describe the photoelectric effect. Based on the photoelectric effect,
what did Einstein conclude about the nature of light?
19. How does the energy of a photon of electromagnetic energy change as
the frequency increases? As the wavelength increases?
20. How did Bohr’s atomic model explain the fact that the atomic emission
spectrum of an element consists of lines of only certain colors?
21. How many energy sublevels are available in the third principal energy
level? How many electrons can each of these sublevels hold?
22. In what significant way does the modern model of the atom differ
from Bohr’s model?
23. Identify the elements that have the following electron configurations.
a. [He]2s22p5
b. [Ar]4s23d5
c. [Ar]4s23d104p2
d. [Ne]3s1
e. [Kr]5s14d8
f. [Xe]6s24f145d106p4
g. 1s22s22p63s23p4
h. 1s22s22p63s23p64s23d104p65s24d10
24. What electrons do the dots in an electron-dot structure represent?
Why are these electrons important?
25. List three elements that have the electron-dot structure •X•.