Download III. Quantum Model of the Atom

Electrons in Atoms
III. Quantum
Model
of the Atom
Quantum Numbers
Four Quantum Numbers:
Specify the “address” of each electron
in an atom
UPPER LEVEL
Quantum Numbers
1. Principal
Quantum Number ( n )
• Energy level
• Relative Size of the orbital
• n = # of sublevels in that energy level
• n2 = # of orbitals in
the energy level
• 2n2 = total # of electrons in that energy
level
Quantum Numbers
2. Angular Momentum Quantum # ( l )
• Is equal to… (n-1)
•Energy sublevel
•Shape of the orbital
s
p
d
f
Quantum Numbers
3. Magnetic Quantum Number ( ml )
Orientation of orbital can be (–l to +l)
Specifies the exact orbital
within each sublevel
Quantum Numbers
px
py
pz
Quantum Numbers
n = # of sublevels per energy level
n2 = # of orbitals per energy level
Orbitals per sublevel: 1 s, 3 p, 5 d, 7 f
Quantum Numbers
Orbitals combine to form a spherical
shape.
2px
2py
2s
2pz
Quantum Numbers
4. Spin Quantum Number ( ms )
Electron spin  +½ or -½
An orbital can hold 2 electrons that spin
in opposite directions.
Quantum Numbers
No two electrons in an atom can have the
same 4 quantum numbers.
Each e- has a unique “address”:
1. Principal #
2. Ang. Mom. #
3. Magnetic #
4. Spin #




energy level
sublevel (s,p,d,f)
orbital
electron
Questions
If n = 3, what l values are
available?
If n = 2, how many
orbital's are possible?
If 32 electrons fit into a
energy level, what is the
lowest possible energy
level?
If l = 2, what sublevel is
the electron in, and how
many orbital's are
present?
0, 1, 2
4
4
d, 5 orbital's in that
sublevel