1. You will learn how to write:
electron configuration
noble gas configuration
orbital configuration
Lewis Dot
You will learn the principals of:
Aufbau
Hund’s
Pauli Exclusion

2. Only electrons are involved with chemical reactions
QUANTUM MECHANICS
It’s all about electrons
Only electrons are involved with chemical reactions
Review electron: location charge symbol
Quantum # tell you 4 things:
l. Main energy level
2. shape of orbit
3. orientation
4. spin

3. ENERGY INCREASES AS ATOM GET BIGGER
Principle Quantum #: energy level of electron indicates distance from nucleus
) 2 ) 8 ) 18 ) 32 )
2N2
ENERGY INCREASES AS ATOM GET BIGGER

4. Principle Quantum #: energy level of electron indicates distance from nucleus
) 2 ) 8 ) 18 ) 32 )

5. Principle quantum number represented by 2n2
7 periods on PT
7 energy levels for e-
Calculate #e- using 2n2
N represents energy level

6. Angular Momentum Quantum #
Indicates shape of orbit s p d f
S (can hold) 2e-
P (can hold) 6e-
D (can hold) 10e-
F (can hold) 14e-

7. B O Al “ Electron Configuration”
Now that you have learned principle quantum number and angular momentum quantum number you can now learn to write
“ Electron Configuration”
) ) ) )
1s2 ) 2s2 2p6 ) 3s2 3p6,3d10 ) 4s2 4p6 4d10 ) 5s2 5p6 5d10 B O Al

8. Aufbau Principle : Cobalt Krypton Silver
an e- will occupy lowest level of energy available
4s2 will fill before 3d10
1s2 ) 2s2 2p6 ) 3s2 3p6, 4s2 3d10 4p6 5s2 4d10 5p6…
Cobalt
Krypton
Silver

10. 1s2
2s2 2p6
3s2 3p6 3d10
4s2 4p6 4d10 4f14
5s2 5p6 5d10 5f14
6s2 6p6 6d10 6f14
7s2 7p6 7d10 7f14

11. Noble Gas Notation Ne Ar Kr Xe Rn
Did you notice how you had to write the first few electron configurations over and over?
Uck!!! Simplify using Noble Gas Notation
On periodic chart elements on far right are called … noble gases He Ne Ar Kr Xe Rn
The have nice complete energy levels with no e- left over.
They do not react with anything.

12. To simplify electron configuration we can use the noble gases.Na P Co K

14. Orbital Notation
Magnetic Quantum # …orientation…x y z
1s2 , 2s2 2p6
px , py , pz
1s2, 2s2 2p6, 3s2 3p6 4s2, 3d10
dx2y2, dxy, dyz, dxz, dz2
Spin Quantum # … which way e- spins – ½ +½

15. Orbital notation shows magnetic & spin quantum #
Hund’s principle: orbitals of equal energy are each occupied by one e- before any orbitals are occupied by a 2nd e-.
Orbital notation shows magnetic & spin quantum #
Boron
Phosphorus
Chromium

17. Can you identify these elements….backwards
5p3
4s1
4d8
2p2
5p4
5d1
4d11
3d8

18. 3 rules governing electron configuration
Aufbau Principle
Hund’s Principle :
Pauli’s Exclusion Principle: .

19. Aufbau Principle
An electron occupies
The lowest-energy level that can receive it.

20. Hund’s Principle:
Orbital's of equal energy are occupied by one electron before any orbital is occupied by a second electron
and all electrons in single occupied orbital's must have the same spin.

21. Pauli’s Exclusion Principle: No two electrons in the same atom
can have the same set of four quantum numbers.

22. Block location tells what orbital being filled
Block location tells what orbital being filled. s p d f Group location tells # of valence electrons

23. 4s1
6s2
4p1
4p5
4s2 3d3
5s2 4d9

24. 3 methods to represent electron locations
1. Electron configuration
2. Noble Gas configuration
3. Orbital Notation
Fourth and final….
Lewis Dot configuration

25. Lewis Dot configuration
Valence electrons: electrons in outer energy level.
**** only outside electrons involved in Chemical Reactions**** B O Al K Cl
There is a secret=== group # tells valence electrons

26. 8. Sodium Carbon 9. Potassium Nitrogen Fluorine Phosphorus Silicone
Bromine
Beryllium
Sulfur
Chlorine
Ws. 4.5 Lewis Dot
Carbon
Nitrogen
Phosphorus
Sulfur
Aluminum
Krypton
Calcium

27. You will learn how to write:
electron configuration
noble gas configuration
orbital configuration
Lewis Dot
You will learn the principals of:
Aufbau
Hund’s
Pauli Exclusion