1. Warmup - do this on a left page, it can be on the page with another warmup
Write on a whiteboard 5 things you know about the periodic table.
Discuss with your table group.

2. We will learn about electron orbital notation
I will complete an electron orbital notation worksheet.
Success Criteria:
Know how to determine the electron orbital notation for an element.
Know the three rules that govern orbital filling.

3. Electron orbitals
Remember how we were comparing electron orbital structures to an apartment building?
Each energy level is a floor of the building.
Each sublevel is a type of apartment on that floor.
The number of orbitals for each sublevel is how many rooms that apartment has.
A maximum of two electrons can occupy each room.

4. How many electrons in each sublevel?
Energy Level
Sub-levels
Total Orbitals
Total Electrons
Total Electrons per Level
n = 1 s
1 (1s orbital) 2
n = 2 p
1 (2s orbital)
3 (2p orbitals) 6 8
n = 3 d
1 (3s orbital)
3 (3p orbitals)
5 (3d orbitals) 10 18
n = 4 f
1 (4s orbital)
3 (4p orbitals)
5 (4d orbitals)
7 (4f orbitals) 14 32
You should already have this in your notes.

5. So what’s important from that table?
You need to know how many orbitals are in each sublevel.
s has 1 orbital
p has 3 orbitals
d has 5 orbitals
f has 7 orbitals
Each orbital can hold 2 electrons

6. Rules for Electron Configurations https://teach. lanecc
In order to write an electron configuration, we need to know the RULES.
3 rules govern electron configurations.
Aufbau Principle
Pauli Exclusion Principle
Hund’s Rule
Copy the chart on the left into your notes.

7. Rules of Electron Orbitals
There are three rules of writing electron orbital diagrams:
The Pauli Exclusion Principle states that no two electrons can occupy the same quantum state (bedroom).
Incorrect: Correct:
1S22S S22S2
↑↑ ↑↑ ↑↓ ↑↓
I’m not like everybody else rule - I spin the other way.

8. The Aufbau principle states that electrons fill in energy levels starting at the bottom (1st floor) and working their way up.
Incorrect: Correct:
1S2 3S S22S2
↑↓ ↑↓ ↑↓ ↑↓
The Lazy Rule - do the easiest levels first.

9. Hund’s rule states that electrons will occupy their own sublevel orientation (apartment) before sharing one with another electron.
Incorrect:
1S2 2S P3
↑↓ ↑↓ ↑↓ ↑
The empty bus rule - don’t share a seat until you have to.

10. Electron Orbital Notation
For each element, an electron orbital notation can be written to indicate the location or “address” of each electron within the atom.
Hydrogen has only one electron, and its notation is:
1S1 ↑
Each part of the notation relates to a specific quantum number:
1 is the principal quantum number and indicates the energy level .
S is the azimuth quantum number (sublevel shape - sphere).
1 is the number of electrons occupying that sublevel.
↑ indicates the spin direction.

11. ↑↓ Helium has two electrons, and its notation is: 1S2
Each electron is in the first energy level and occupies a sphere- shaped orbital.
Each electron spins in a different direction, shown by the arrows.
Remember, each S sublevel can only fit two electrons, so this “apartment” is now full.

12. At this point, it is helpful to divide the periodic table blocks to indicate which sublevel is being filled, and in which order.

13. ↑↓ ↑ 1S22S2 ↑↓ ↑↓ 1S22S22P1 ↑↓ ↑↓ ↑ Lithium has three electrons,
↑↓ ↑
Beryllium has four, and now the 2S “apartment” is full.
1S22S2
↑↓ ↑↓
Boron has five electrons. The fifth has to move into the first 2P “apartment”.
1S22S22P1
↑↓ ↑↓ ↑

14. Unlike 1S and 2S, the 2P block has 3 “apartments”
Unlike 1S and 2S, the 2P block has 3 “apartments”. By the time we get to neon, all of those are now full.
1S2 2S P6
↑↓ ↑↓ ↑↓ ↑↓ ↑↓
Notice that the second energy level is now completely full. The atom will have to add another “floor” to accommodate more electrons.

15. We will complete the electron configurations worksheet together to put in the notebooks.
Get out the scissors and cut the page off where #10 ends on the back.
We are going to do #1-3 on the front and parts B and C on the back.
We are not going to do #4-6 on the front because they actually require more space than is given.

16. I will talk you through the first one.

17. We’ll do #2 together and then I want you to try #3.

18. We’re going to use the chart below to get the answers to Part B.

19. Now we’re going to look at Part C and answer those questions together.

20. Tape this on a left side and label it Electron Configuration practice.
I’m going to pass out the worksheet that you’ll be doing for the rest of class. This will be due at the start of next class.

21. Practice worksheet
Complete your practice worksheet for next class. You have the rest of class to work on this
EXTRA CREDIT OPPORTUNITY!
I have a review sheet that is worth up to 5 points extra credit on the test if turned in by next class. It will not be accepted after that. It must be COMPLETE in order to be accepted. Attempt every problem.

22. Have a nice day.