1. Arrangement of Electrons in Atoms
Electron Configurations

2. Review of Sections 1 & 2
What is the equation that related speed, wavelength, and frequency?
Which theory of light, (wave or particle) best explains the following phenomena?
a. The interference of light
b. The photoelectric effect
c. The emission of electromagnetic radiation by an excited atom.
Compare and contrast the Bohr model and quantum-mechanical model of the atom.
What is the principal quantum number?

3. Review of Sections 1 & 2
How does “n” relate to the number of sublevels in each energy level?
For n = 4, how many sublevels are there and what are their designations?
How many possible orbital orientations are there for d and f sublevels?
What is the relationship between n and the total number of orbitals in each energy level?
How many electrons could be contained in the 3rd energy level?

4. Electron Configurations
Orbital Notation for Carbon
  _ _ __
1s 2s 2p
Electron Configuration for carbon
1s22s22p2

6. “Orbital Filling” Rules
Aufbau Principle
Electrons fill the lowest energy orbitals available
Pauli Exclusion Principle
No two electrons in the same atom can have the same set of four quantum numbers; orbitals can hold a maximum of two electrons; two electrons in one orbital must have opposite spins.
Hund’s Rule
Electrons fill equal energy orbitals one at a time until each is occupied by one electron; Electrons in singly occupied orbitals have the same spin.

7. Write orbital diagrams and electron configurations for each of the following atoms.
N F S Cl Se Te Ar Ne