1. EXAM #3 HAS BEEN MOVED TO MONDAY, NOVEMBER 9TH
October 30, 2009
EXAM #3 HAS BEEN MOVED TO MONDAY, NOVEMBER 9TH

2. The First Three Quantum Numbers
n, l, and ml are integers
n = principal quantum # = 1, 2, 3, …
n tells us the size/energy of the orbital
l = angular momentum quantum # = 0, 1, 2, …, n-1
l tells us the shape of the orbital- s,p,d,f…
ml = magnetic quantum number = –l to l
ml describes the orientation of the orbital

3. Hydrogen

4. Nodes 1s (1,0) 2s (2,0) 1 2p (2,1) 3s (3,0) 2 3p (3,1) 3d (3,2) 4s
Orbital
(n,l)
Planar
Spherical
Total 1s
(1,0) 2s
(2,0) 1 2p
(2,1) 3s
(3,0) 2 3p
(3,1) 3d
(3,2) 4s
(4,0) 3 4p
(4,1) 4d
(4,2) 4f
(4,3)

5. Nodes, Revisited # of planar nodes = l
# of spherical nodes = n – l – 1
Total # nodes = n – 1
Example: 3d orbital

6. What orbital has these quantum numbers? n = 3, l = 2, ml = -14p 3d 3p 1d 2f

7. What are the quantum numbers for the 5dxy orbital?
n = 5, l = 2, ml = 0
n = 5, l = -2, ml = 3
n = 4, l = 2, ml = 2
n = 5, l = 3, ml = 0
n = 5, l = 2, ml = -5

8. Which is not a valid set of quantum numbers?
n = 4, l = 1, ml = -1
n = 1, l = 0, ml = 0
n = 6, l = 5, ml = -5
n = 2, l = 2, ml = 1
n = 3, l = 2, ml = 2

9. The representation 5d indicates which values for n and l?
n = 5; l = 0
n = 5; l = 1
n = 5; l = 2
n = 5; l = 3

10. What is the total number of nodes for the 5d orbital?1 2 3 4

11. How many spherical nodes does a 5d orbital have?1 2 3 4

12. How many planar nodes does a 5d orbital have?1 2 3 4

13. The Fourth Quantum Number
n, l, and ml are integers
n = principal quantum # = 1, 2, 3, …
n tells us the size/energy of the orbital
l = angular momentum quantum # = 0, 1, 2, …, n-1
l tells us the shape of the orbital- s,p,d,f…
ml = magnetic quantum number = –l to l
ml describes the orientation of the orbital
ms is not an integer
ms= spin quantum number = - ½ or ½

14. Electrons Spin
Classical physics a spinning charge creates a magnetic field
Electron spin* is quantized; the two states are called “spin up” and “spin down”
*Electrons are described by quantum physics and don’t really “spin”

15. Electron Spin is the Source of Magnetism in Materials
Diamagnetic
Paramagnetic
Ferromagnetic (“real magnets”)