1. Using Quantum Numbers to Describe Electrons
Clouds probable location for electrons

2. Quantum Numbers Four numbers that describe the shape of the cloud.
Described using the variables: n, l, m, s.

3. “n” = the Principle Quantum Number(Energy Quantum #)
Corresponds to periodic table’s horizontal row.
n = 1
n = 2
n = 3

4. “n” = the Principle Quantum Number(Energy Quantum #)
Higher number, more energy
higher number, bigger cloud
2n2 is how many electrons may have that energy

5. “l” sublevel Found within “n” Sublevels – s,p,d,f
Each orbital can have at most two electrons.

6. “s” spin Quantum Number
s = 1/2 is clockwise (up)
s = -1/2 is counter-clockwise (down)

7. Quantum Number
Keep in mind are probabilities of finding electrons in certain places doing certain things(spin).
n = what energy level (1, 2, 3, )
l = what sub-level (s, p, d, or f)
m = orientation of orbital (s=1; p=3; d=5; f=?)
s = which spin (only two possibilities up or down)

8. Pauli Exclusion Principle
No two electrons ever have the same four quantum numbers in the same atom.
Just as no two houses have the same address

9. Quantum #s n - tells the size and energy l - tells the shape
m - tells how the shape fits on the x, y, z axes
s- tells about spin.