1. Periodic blocks energy level is equal to period
s block holds 2 electrons
p block holds 6 electrons
d block holds 10 electrons
f block holds 14
electrons

2. s Orbital

3. p Orbitals

4. d and f Orbitals

5. Noble Gas Configuration

6. Noble Gases & Noble Gas Notation
Noble Gas – Group 18 of the Periodic Table. They contain full valence shells.
Noble Gas Notation – Noble gas is used to represent the core (inner) electrons and only the valence shell is shown. Br
Electron configuration 1s 2s 2p 3s 3p 2 6 4s 3d 10 4p 5
Noble gas
[Ar] 4s 2 3d 10 4p 5
The “[Ar]” represents the core electrons and only the valence electrons are shown

7. Which Noble Gas Do You Choose?
How do you know which noble gas to use to symbolize the core electrons?
Think: Price is Right.
How do you win on the Price is Right?
By getting as close as possible without going over.
Choose the noble gas that’s closest without going over!
Noble Gas
# of electrons He 2 Ne 10 Ar 18 Kr 36 Xe 54

8. Noble Gas Chart

9. Noble Gas Notation Example1
Determine the number of electrons to place 2
Determine which noble gas to use
Start where the noble gas left off and write spectroscopic notation for the valence electrons 3
Example:
Write noble gas notation for As

10. Noble Gas Notation Example1
Determine the number of electrons to place 2
Determine which noble gas to use
Start where the noble gas left off and write spectroscopic notation for the valence electrons 3
Example:
Write noble gas notation for As
Atomic number for As = 33 = # of protons
Electrons = 33
Closest noble gas: Ar (18)
[Ar] 4s 3d 4p 2 10 3
Ar is full up through 3p 18 + 2 + 10 + 3 = 33

11. Electrons in beryllium (not in Helium)
Example #1
Beryllium
Helium is the noble gas one row above Beryllium
Beryllium also has 2 electrons in the 2s energy sublevel
[He] 2s2
Electrons in beryllium (not in Helium)
Noble Gas

12. Electrons in Sulfur (not in Neon)
Example #2
Sulfur
Neon is the noble gas one row above Sulfur
Sulfur also have 2 electrons in 3s and 4 electrons in 3p energy sub levels
[Ne]3s23p4
Electrons in Sulfur (not in Neon)
Noble Gas

13. Example #3 Iron Argon is the noble gas one row above Iron
Iron also has 2 electrons in 4s and 6 electrons in 3d energy sublevels
[Ar]3d64s2

14. Example #4 Uranium Radon is the noble gas one row above Uranium
Uranium also has 2 electrons in 7s, 1 electron in 6d, and 3 electrons in 5f energy sublevels
[Rn]7s25f4