Download Atomic Orbitals and quantum numbers

Quantum Numbers
•Four Quantum Numbers:
•Specify the “address” of each electron in
an atom
UPPER LEVEL
Courtesy Christy Johannesson www.nisd.net/communicationsarts/pages/chem
Quantum Numbers
•Principal ( n )
•Angular Momentum ( l )
•Magnetic ( ml )
•Spin ( ms )
1. Principal Quantum Number (n)
• Energy level
1s
• Size of the orbital
• n2 = # of orbitals
2s
in the energy level
3s
Courtesy Christy Johannesson www.nisd.net/communicationsarts/pages/chem
1s orbital imagined as “onion”
Concentric spherical shells
Copyright © 2006 Pearson Benjamin Cummings. All rights reserved.
Angular Momentum (l)
•Defines the shape of the orbital.
• Energy sublevel
•Allowed values of l are integers ranging
from 0 to n − 1.
•We use letters to describe the different
values of l and, therefore, the shapes and
types of orbitals.
Value of l
0
1
2
3
Type of orbital
s
p
d
f
Magnetic Quantum Number, ml
•Describes the three-dimensional orientation
of the orbital.
•Values are integers ranging from -l to l:
−l ≤ ml ≤ l.
•Therefore, on any given energy level, there
can be up to 1s orbital, 3p orbitals, 5d orbitals,
and 7f orbitals.
l=0 (s), m=0
l=1 (p), m=-1,0,1
l=2 (d), m=-2,-1,0,+1,+2
l=3 (f), m=-3,-2,-1,0,+1,+2,+3
Energy Levels, Orbitals, Electrons
Energy
Level
(n)
Orbital type
in the
energy level
(types = n)
Number of
Orbitals
(m)
Number of
Electrons
Number of
electrons per
Energy level
(2n2)
1
s
1
2
2
2
s
p
1
3
2
6
8
3
s
p
d
1
3
5
2
6
10
18
4
s
p
d
f
1
3
5
7
2
6
10
14
32
A maximum of two electrons can occupy an orbital
Electron Spin
Electron spin describes the behavior
(direction of spin) of an electron within a
magnetic field, which affects its energy.
Possibilities for electron spin:
1

2
1

2
Indicates two fundamental spin
states of an electron in an orbital.