"

Chapter 3 – Practice Problems (Atomic Theory)

  1. List the three statements that make up the modern atomic theory.
  2. Explain how atoms are composed.
  3. Which is larger, a proton or an electron?
  4. Which is larger, a neutron or an electron?
  5. What are the charges for each of the three subatomic particles?
  6. Where is most of the mass of an atom located?
  7. Sketch a diagram of a boron atom, which has five protons and six neutrons in its nucleus.
  8. Sketch a diagram of a helium atom, which has two protons and two neutrons in its nucleus.
  9. Define atomic number. What is the atomic number for a boron atom?
  10. What is the atomic number of helium?
  11. Define isotope and give an example.
  12. What is the difference between deuterium and tritium?
  13. Which pair represents isotopes?
    • a. [latex]\ce{^{4}_{2}He}[/latex] and [latex]\ce{^{3}_{2}He}[/latex]
    • b. [latex]\ce{^{56}_{26}Fe}[/latex] and [latex]\ce{^{56}_{25}Mn}[/latex]
    • c. [latex]\ce{^{24}_{14}He}[/latex] and [latex]\ce{^{31}_{15}P}[/latex]
  14. Which pair represents isotopes?
    • a. [latex]\ce{^{40}_{20}Ca}[/latex] and [latex]\ce{^{40}_{19}K}[/latex]
    • b. [latex]\ce{^{56}_{26}Fe}[/latex] and [latex]\ce{^{56}_{28}Fe}[/latex]
    • c. [latex]\ce{^{238}_{92}He}[/latex] and [latex]\ce{^{235}_{92}U}[/latex]
  15. Give complete symbols of each atom, including the atomic number and the mass number.
    • a. An oxygen atom with 8 protons and 8 neutrons
    • b. A potassium atom with 19 protons and 20 neutrons
    • c. A lithium atom with 3 protons and 4 neutrons
  16. Give complete symbols of each atom, including the atomic number and the mass number.
    • a. A magnesium atom with 12 protons and 12 neutrons
    • b. A magnesium atom with 12 protons and 13 neutrons
    • c. A xenon atom with 54 protons and 77 neutrons
  17. Americium-241 is an isotope used in smoke detectors. What is the complete symbol for this isotope?
  18. Carbon-14 is an isotope used to perform radioactive dating tests on previously living material. What is the complete symbol for this isotope?
  19. Give atomic symbols for each element.
    • a. sodium
    • b. argon
    • c. nitrogen
    • d. radon
  20. Give atomic symbols for each element.
    • a. silver
    • b. gold
    • c. mercury
    • d. iodine
  21. Give the name of the element.
    • a. Si
    • b. Mn
    • c. Fe
    • d. Cr
  22. Give the name of the element.
    • a. F
    • b. Cl
    • c. Br
    • d. I

License

Icon for the Creative Commons Attribution-NonCommercial 4.0 International License

CHM130 Fundamental Chemistry Copyright © by Mesa Community College is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License, except where otherwise noted.