Download Quantum Numbe

1. Electrons have a dual nature – they can be both
particles and waves
- Bohr: an electron should be treated as a particle
- Schroedinger: an electron should be treated as a
wave
2. Electrons form a cloud about the nucleus
3. Heisenberg’s Uncertainty Principle states
the momentum and location of an electron
can’t be known with equal certainty at
same time
4. Schrodinger developed mathematical
equations to explain behavior of electron
5. The quantum numbers are analogous to an atomic
“zip code” for the location and energy of an
electron
- There are four quantum numbers for each electron
- Specify the “address” of each electron in an atom
- We could also compare it to a seat in a sports
stadium
UPPER
LEVEL
6-8. The First Quantum Number
6. Assigned the letter “n”
7. It corresponds to the principal energy level
(shell)
8. It starts with 1 and goes up to 7 but can go
higher if needed
9-10. The First Quantum Number
9. The total number of electrons in an energy
level is represented by the equation 2n2
where “n” is the energy level
10.“n” also stands for the size of the electron
cloud
- The larger the “n” value the larger the cloud.
11-13. The Second Quantum Number
11. Represented by the letter “l”
12. It describes the sublevels or subshells
within an energy level
13. The number of sublevels in an energy level
is equal to the energy level number
14-17. The Second Quantum Number
14. The sublevels are given letters “s,p,d,f”
15. Sublevels of one energy level can overlap
those of another
16. Each sublevel holds a maximum number of
pairs of electrons: s-1; p-3; d-5; f-7
17. Also describes the probability shape of an
orbital
Principal
Energy Level
Number of
Sublevels
Designation *
n=1
1
s
n=2
2
s, p
n=3
3
s, p, d
n=4
4
s, p, d, f
n=5
5
s, p, d, f, (g)*
n=6
n= 7
6
7
s, p, d, (f, g, h)
s, p, (d, f, g, h, i)*
*Letters in parenthesis are unfilled sublevels.
They are present but not used
18. Orbital - the area of 3 dimensional
space where there is a 90% possibility of
finding an electron
Orbital
Radial Distribution Curve
19. Orbital shapes
s-Orbitals: All s-orbitals are spherical in shape
s-Orbital
p-Orbitals: All p-orbitals have a dumbell shape
p-Orbital
d-Orbitals: d-Orbitals have the following clover shape
d-Orbital
f-Orbitals: f-Orbitals are even more complicated
f-Orbital
13
20. Orbitals combine to form a spherical
shape
2s
2px
2py
2pz
21-22. The Third Quantum Number
21. Designated by the letter “m”
22. Indicates the direction in space of each
orbital. It also stands for the orbital
23-24. The Third Quantum Number
23. An orbital in “s” sublevel has 1 orientation
•  An orbital in “p” sublevel has 3 orientations
•  An orbital in “d” sublevel has 5 orientations
•  An orbital in “f” sublevel has 7 orientations
24. Degenerate Orbital: Orbitals that are
alike in size and shape and differ in only one
direction have the same energy
25-26. The Fourth Quantum Number
25. Represented by the letter “s”
•  Indicates the spin of an electron
•  Can be clockwise or counterclockwise
26. Pauli Exclusion Principle- “No two electrons
in an atom can share the same set of four
quantum numbers. If the first three are the
same, then the last- their spin- will be
different”
27.
1. First # “n” à energy level (n= 1-7)
2. Second # “l” à sublevel (s,p,d,f), shape
3. Third # “m” à orbital, orientation (1, 3, 5,
7)
4. Fourth # “s” à spin (-1/2 or +1/2)