Lesson Plans

Chemistry: The Central Science 9th Edition ©2003

by Brown, LeMay, and Bursten

Weeks 6–7: Electron Structure and Periodicity

Chapter 6: Electron Structure of Atoms
Chapter 7: Periodic Properties of the Elements

This lesson studies the electronic structure of the atom and relates it to the periodic table. Although two weeks are suggested, the objectives can probably be completed in a shorter period. The rest of the time can be used to catch up on other activities, such as labs, that were skipped because of time constraints.

College Board Performance Objectives:

• Understand the relationships c = and E = h.
• Understand the concept of a quantized atom and its relationship to a line spectra of atoms.
• Explain the concept of ionization energy.
• Describe the Uncertainty Principle and its affect on atomic theory.
• Understand the relationship = h/mv and its affect on atomic theory.
• Describe how quantum numbers define electron orbitals and their value limitations.
• Describe the shapes of the orbital types.
• Understand the concept of electron spin and how it relates to electron configuration.
• Write the electron configuration both symbolically and as an orbital diagram for any element.
• Be able to write electron configurations, especially valence configurations, for any element, using the periodic table with the knowledge of the s,p,d, and f blocks.
• Describe the variations of atomic radii in the groups and periods on the periodic table and the underlying reasons for the variations.
• Describe and explain the observed changes in successive ionization energies for a given atom.
• Describe the variations in first ionization energies in the groups and periods on the periodic table and the underlying reasons for the variations.
• Do the same with the electron affinities of the elements.
• Describe the periodic trends in metallic and nonmetallic behavior and chemical activity.

College Board Lab Objectives:

Suggested Labs:

Resources:

• Instructor's Resource Manual, pp. 66–88
• Student's Guide, pp. 102–155
• Test Bank, pp. 211–306
• Instructor's Resource CD, Chapters 6–7

Pacing Guide:

• Electron Energy Levels and Quantum Mechanics—3 days
• Electron Configurations and the Periodic Table—3 days
• Periodic Relationships: Atomic Radii, Ionization Energy, Electron Affinity, and Oxidation State—3 days
• Block Scheduling
  Spend very little time on the history of atomic theory and the periodic table. Get right into the modern atom, using models as necessary. Two blocks of time should be adequate. Spend at least three blocks on how the configuration explains periodic relationships. As always, doing the exercises is very important!

Key Words:

Suggested Exercises:
Critical thinking questions and end-of-chapter activities are included in these exercises.

• pp. 230–235, # 3, 7,9,11,13,17, 19, 21, 23, 27, 31, 33, 39, 41, 43, 45, 49, 51, 53, 55, 57, 59, 61, 63, 71, 73, 79, 81.
• eMedia Exercise: p. 235, # 92, 93, 94, 95.
• pp. 266–273 , # 3, 5, 7, 11, 15, 17, 19, 21, 23, 25, 27, 29, 31, 33, 35, 37, 39, 43, 45, 47, 49, 51, 53, 55, 57, 59, 61, 63, 69, 71, 73, 82, 84, 86.
• eMedia Exercise: pp. 272–273, # 101–104, 106–108.

Troubleshooting Tips/Error Traps:

• Orbitals are areas of highest probability of finding the electron, not the path of the electron.
• Electron shells in an atom are diffuse and overlap considerably.
• Electron affinity is not the opposite of ionization energy.