Chapter 6
Predicting Outer Electron
Configurations
Parts 1 & 2
Electron Configurations
•
11Na
•
19K
•
16S
•
34Se
•
22Ti
•
40Zr
Period # = Outer Energy Level
Includes lanthanides
Includes actinides
Elements in the Same Group
• Elements in the same group have similar properties
because they have similar electron configurations.
Sublevel Blocks of the Periodic Table
Not all periodic tables
look exactly the same.
Not all periodic tables
look exactly the same.
o
Blank Periodic Table
Periodic Table and Electron Configuration
s = period #
p = period #
1
1
2
2
3
d = (period# - 1)
3
4
4
5
5
6
6
7
7
6
6
7
7
f = (period# - 2)
Predict the electron configuration for the last sublevel.
•
20Ca
o
Predict the electron configuration for the last sublevel.
•
20Ca
•
82Pb
o
Predict the electron configuration for the last sublevel.
•
20Ca
•
82Pb
•
47Ag
o
Predict the electron configuration for the last sublevel.
•
20Ca
•
82Pb
•
47Ag
•
92U
o
Periodic Table and Electron Configuration
s = period
p = period
1
2
d = (period-1)
3
4
5
6
7
6
7
6
7
f (period-2)
© 1998 by Harcourt Brace & Company
1
2
3
4
5
6
7
6
7
Abbreviated Electron Configurations:
“A Shortcut”
Write the electron configuration for lead (Z = 82) using the
periodic table.
O
6
7
© 1998 by Harcourt Brace & Company
Notes: Abbreviated Electron Configuations
82Pb
has the following electron configuration:
1s22s22p63s23p64s23d104p65s24d105p66s24f145d106p2
Notes: Abbreviated Electron Configuations
82Pb
has the following electron configuration:
1s22s22p63s23p64s23d104p65s24d105p66s24f145d106p2
54Xe
2
has the following electron configuration:
2
6
2
6
2
10
6
2
10
6
1s 2s 2p 3s 3p 4s 3d 4p 5s 4d 5p
C. Periodic Patterns
• Example – Germanium (Z = 32)
1
2
3
4
5
6
7
[Ar]
2
4s
10
3d
2
4p
Write the electron configurations.
20Ca
94Pu
77Ir
Write the electron configurations.
• 20Ca = [Ar]4s2
• 94Pu = [Rn]7s25f6
• 77Ir = [Xe]6s24f145d7
Homework
• Worksheet: Electron Configuration and the Periodic
Table.
• Worksheet : Predicting electron configurations
 Make sure you use the periodic table suggested for
your assignment or your answers may vary slightly.