Orbital Filling Diagrams and

1
Chapter 5

• Orbital Filling Diagrams and
• Electron Dot Diagrams

2
Orbital Filling Diagrams

• Orbital filling diagrams illustrate the pairing
  of the electrons in an atom.

3
Remember how we illustrate the sublevels with
boxes.
4
An s sublevel has one orbital

5
A p sublevel has three orbitals

6
A d sublevel has five orbitals

7
An f sublevel has seven orbitals

8
Pauli Exclusion Principle

• Each orbital can hold TWO electrons with opposite
  spins.

9
Hunds Rule

• Within a sublevel, place one e- per orbital
  before pairing them.
• All electrons in singly filled orbitals have the
  same direction of spin.

10
A. General Rules

• Which orbital filling diagram correctly follows
  Hunds Rule for p4?

RIGHT
WRONG
11
(No Transcript)
12
Orbital Filling Diagrams
13
B. Notation

• Orbital Diagram for oxygen (1s22s22p4)

O 8e-
How many of oxygens electrons are paired?
14
What type of sublevel is this?

15
Make the orbital filling diagram for d8

How many of the electrons are unpaired?
16
What type of sublevel is this?

17
Make the orbital filling diagram for f9

How many of the electrons are paired?
18
How many electrons in an Fe atom are
paired?(Shortcut for Determining the pairing of
electrons.)

• What is the electron configuration of Fe? (Z
  26)
• 1s2 2s2 2p6 3s2 3p6 4s2 3d6
• 4 electrons are unpaired
• 22 electrons are paired

19
Electron Dot Diagrams

• Step 1 Write the electron configuration

20
Electron Dot Diagrams

• Step 2 Determine the number of valence
  electrons.
• The valence electrons are the electrons in the
  outer energy level.

21
Electron Dot Diagrams

• Step 3 Write the symbol of the element
  surrounded by valence electrons. Place one
  electron on each side (top, bottom, right, left)
  before pairing them up.

22

• Draw the electron dot diagram for oxygen.

23
Draw the electron dot diagram for selenium. (Z
34)
24
Draw the electron dot diagram for chlorine. (Z
17)
25
Draw the electron dot diagram for hydrogen. (Z
1)
26
HCl vs H2O

• When hydrogen combines with chorine it does so in
  a 11 ratio.
• When hydrogen combines with oxygen it does so in
  a 21 ratio.
• Why?

27
Preview Lewis Structures

• Lewis structures will not be part of this chapter
  test but they illustrate a common use of electron
  dot diagrams.

28
Homework

• Worksheet Orbital Filling Diagrams Electron
  Dots.
• Study Guide Chapter 5