Pick Up:
•Electron Notes
•Periodic Table
•4 different colored
pencils
Electrons are important because they
determine how elements will bond and react
with other elements.
Electron Configuration –
tells us the location of an element’s
electrons.
Heisenburg Uncertainty Principle – It is
impossible to know the exact location and
speed of an electron at the same time
Energy Levels –
give the general distance from the nucleus
Sublevels – the areas within the energy
levels where the electrons are found.
s
p
d
f
Electron Configuration
1
1s
# of electrons
s: 1 or 2
p: 1-6
Energy Level –
d: 1-10
Principle Quantum #
f: 1-14
(possibilities are 1-7)
When all written out,
Total e- should equal
Sublevel
Atomic #
(possibilities are
s, p, d, or f)
What element has an electron configuration of 1s1?
1
1s
2
2s
2p
3
3s
3p
4
4s
5
6
1s
s
d
4p
5p
p
7
6
7
f
Instructions:
Color each section with a different color – be careful with Helium!
THEN write the electron configuration in each box for s and p blocks
Aufbau Principle
• Electrons fill the sublevel of lowest energy
first.
1s2 2s2 2p6 3s2 3p6 4s2 3d6
Energy
Subshells d and f are “special”
1
2
3
4
5
6
7
3d
4d
5d
6d
d
6 4f
7 5f
f
Instructions:
Write the electron configuration in each box for d and f blocks –
PAY ATTENTION to what number they start with!
Name the element and circle the
sublevel with the highest energy:
Fe 1s2 2s2 2p6 3s2 3p6 4s2 3d6
_____
Os 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6
_____
5s2 4d10 5p6 6s2 4f14 5d6
Bi 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6
_____
5s2 4d10 5p6 6s2 4f14 5d10 6p3
1
2
3
4
5
6
s
d
p
7
6
7
f
Write the electron configuration:
• Br
1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p5
• Pb
1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2
4d10 5p6 6s2 4f14 5d10 6p2
• Er
1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2
4d10 5p6 6s2 4f11
Noble Gas Configuration –
shortcut to electron configs based
on the last noble gas.
• Noble gases are found in Group 18.
• Example:
[Ar] 4s2 3d8
Where [Ar] represents
Argon – the last noble gas filled
Name the element:
S
• _____
[Ne] 3s2 3p4
Os [Xe] 6s2 4f14 5d6
• _____
Sb
• _____
[Kr] 5s2 4d10 5p3
Write the noble gas configuration:
• Se
[Ar] 4s2 3d10 4p4
• Mo
[Kr] 5s2 4d4
• Ar
[Ne] 3s2 3p6
Orbital Notation – visually shows
the location of the electrons.
• Only 2 electrons fit in each orbital.
• Example:
↑__
↓
[Xe] 6s2
↓ __
↑↓
↓ __
↑↓ ↑__
↑↓ __
↑↓
↑ ↓ ↑__
↑↓ __
↑↓ ↑__
↓ __
↑__
↓ __
↑↓ __
__
4f14
5d10
↓ __
↑↓ ↑__
↑
__
6p5
You must draw each orbital, even if it is empty.
• Hund’s Rule –
One electron enters each orbital
until all orbitals have one electron
with parallel spins
• Pauli Exclusion Principle –
No 2 electrons can have the
same location and same spin
Energy
Levels
Sublevels
# of
Orbitals
Maximum
# of electrons
1-7
s
2
6
d
1
3
5
2-7
3-6
p
4-5
f
7
10
14
Draw the orbital notations for the
following elements:
(start with the noble gas config)
• Sn –
• Ba –
• Se –
Lewis Dot Structures – shows the
valence electrons.
• Valence Electrons – outershell electrons
• You can count valence electrons by looking at
the group #. (if it’s a double digit, subtract 10)
Remember Hund’s Rule when drawing Lewis Dots
BUT draw all “s” electrons together on the right.
Examples:
C
Br
Ba
N