1. Pick Up:
Electron Notes
Periodic Table
4 different colored pencils

2. 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

3. 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

4. Electron Configuration
1s1
# of electrons
s: 1 or 2
p: 1-6
d: 1-10
f: 1-14
When all written out,
Total e- should equal
Atomic #
Energy Level –
Principle Quantum #
(possibilities are 1-7)
Sublevel
(possibilities are
s, p, d, or f)
What element has an electron configuration of 1s1?

5. s p d f 1 2 3 4 5 6 7 1s 1s 2s 2p 3s 3p 4s 4p 5p 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

6. Aufbau Principle Electrons fill the sublevel of lowest energy first.
1s2 2s2 2p6 3s2 3p6 4s2 3d6
Energy

7. Subshells d and f are “special”1 2 3 4 5 6 7 d 3d 4d 5d 6d f 4f 5f
Instructions:
Write the electron configuration in each box for d and f blocks –
PAY ATTENTION to what number they start with!

8. Name the element and circle the sublevel with the highest energy:
_____ 1s2 2s2 2p6 3s2 3p6 4s2 3d6
_____ 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d10 5p6 6s2 4f14 5d6
_____ 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d10 5p6 6s2 4f14 5d10 6p3 Fe Os Bi

9. 1 p 2 3 s d 4 5 6 7 f 6 7

10. Write the electron configuration:Br Pb Er
1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p5
1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d10 5p6 6s2 4f14 5d10 6p2
1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d10 5p6 6s2 4f11

11. 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

12. Name the element: S _____ [Ne] 3s2 3p4 _____ [Xe] 6s2 4f14 5d6 Os
_____ [Kr] 5s2 4d10 5p3 Os Sb

13. Write the noble gas configuration:Se Mo Ar
[Ar] 4s2 3d10 4p4
[Kr] 5s2 4d4
[Ne] 3s2 3p6

14. Orbital Notation – visually shows the location of the electrons.
Only 2 electrons fit in each orbital.
Example:
__ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __
[Xe] 6s f d p5
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 s p d f
1 - 7 1 2
2 - 7 3 6
3 - 6 5 10
4 - 5 7 14

15. Draw the orbital notations for the following elements: (start with the noble gas config)
Sn –
Ba –
Se –

16. 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