1. Homework # 10 Worksheet: Quantum Numbers
Assign quantum numbers to the valence electron of a lithium.
3. Assign quantum numbers for the tenth electron to fill a neon atom.

2. Aim 10: How can you describe the quantum mechanical model?

3. Quantum #’s are like an Address.
What do you need to know to find out where you live?
State
City
Street
House
Principle Quantum number
(n)
Angular Quantum number
(ℓ)
Magnetic Quantum number
(mℓ)
Spin
Quantum number (ms)

4. 1. Quantum Numbers
Modern atomic theory states that any electron in an atom can be completely describe by four quantum numbers: n, l, ml ,ms

5. 1st Quantum Number: Principal Quantum Number (n)
Refers to the principal energy levels. n 1 2 3 4

6. 2nd Quantum Number: Azimuthal or Angular Momentum Quantum Number (ℓ)

7. Letter s p d f ℓ can be any integer from 0 to n-1 Sublevel (s,p,d,f)
Describe the shape of the orbital
Letter s p d f ℓ 1 2 3

8. letter s p d f ℓ 1 2 3
Example: n = 3 ℓ = 0 ….n-1 ℓ = 0 ….(3-1) ℓ = 0 to 2

9. S,P,D,F s: Sharp p: Principal d: Diffuse f: Fundamental
The s, p, d, and f stand for "sharp," "principal," "diffuse," and "fundamental," respectively, and are so named because they categorize the spectral lines generated by those types of orbitals: Electron configuration

10. 3rd Quantum Number: Magnetic Quantum Number (mℓ)
Designates the specific three dimensional orientation of the orbital ℓ.

11. s subshell: spherical
1 S
2 S
3 S

12. p subshell : dumbbell shape 3 orbitalsz x y x y z

13. d subshell

14. mℓ can be any integer from: - ℓ to + ℓ
Example: ℓ= 2 mℓ = -2, -1, 0, +1, +2

15. S ___
p ___ ____ ____
d ____ ____ ____ ____ ____
f ____ ____ ____ ____ ____ ____ ____

16. Value of l
Sub
shell
Values of ml
Possible orbitals s S 1 p
-1 , 0 , 1
Px,Py,Pz 2 d
-2, -1, 0, 1, 2
dxy,dxz,dyz,dx2y2, dz2 3 f
-3, -2, -1, 0, 1, 2,3

17. 4th Quantum Number: Spin Quantum Number (ms )
the spin of the electron.
Electrons in the same orbital must have opposite spins. 1 2 1 2 + - or
The value of ms =

18. + ½
- ½
2 S

19. z
+ ½
- ½ y x

20. Possible spins are clockwise or counterclockwise

21. Empty
PARAMAGNETIC
are attracted to a magnetic field
Half-Filled
Filled
MAGNETIC

22. The Pauli exclusion principle (Wolfgang Pauli, Nobel Prize 1945) states that:
no two electrons in the same atom can have identical values for all four of their quantum numbers. What this means is that no more than two electrons can occupy the same orbital, and that two electrons in the same orbital must have opposite spins.

23. Summary

24. Quantum Numbers
n, l, ml, ms
ORBITAL
PEL
SPIN
SUBLEVEL
SHAPE

25. l = SUBLEVEL (s,p,d,f)
S = 0 P = 1 d = 2 F = 3

26. ml = orbital s ___ 0 p ___ ___ ___ - 1 0 1 d ___ ___ ___ ___ ___
d ___ ___ ___ ___ ___
f ___ ___ ___ ___ ___ ___ ___

27. ms = +1/2, -1/2
Spin!

29. TEST YOUR UNDERSTANDING

30. Oxygen s= 0 P = 1 d =2 f= 3 ___ ___ ___ ___ ___ 1s2 2 s2 2p4 s ___ n ln l ml ms 1
1/2

31. Oxygen s= 0 P = 1 d =2 f= 3 ___ ___ ___ ___ ___ 1s 2 s 2p s ___ n l mln l ml ms 1
- 1/2

32. Oxygen s= 0 P = 1 d =2 f= 3 ___ ___ ___ ___ ___ 1s 2 s 2p n l ml ms 2 1 1
1/2

33. 1. An atom of hydrogen has one electron and is labeled 1 s1
1. An atom of hydrogen has one electron and is labeled 1 s1 . What will the quantum be?
n= ℓ= mℓ = ms =

34. 1st: Principal Quantum Number (n)
Answer: n= 1

35. 2nd: The angular momentum quantum Number (ℓ) or subshell
P = 1
d =2
f= 3
1 s1
Answer: ℓ= 0
because ℓ is a number from 0 to n-1

36. 3rd: Magnetic Quantum Number (ml) -l to +l
1 s1
s ___
ml = 0

37. 4th: Spin Quantum Number (ms )1 2
1 s1 +
Answer: 1 2 +

38. The Quantum Numbers are:
1, 0, 0, 1 2

39. 2. Assign quantum numbers to the valence electrons of a lithium atom
1s22s1 See your periodic table

40. 1st: Principal Quantum Number (n)
1s22s1
Answer: n= 2

41. 2nd: The angular momentum quantum Number (ℓ) or subshell
1s22s1
s= 0
P = 1
d =2
f= 3
Answer: ℓ= 0

42. 3rd: Magnetic Quantum Number (ml) -l to +l
1s22s1
s ___
ml = 0 , because the value of l is 0

43. 4th: Spin Quantum Number (ms )1 2
1s22s1 +
Answer: 1 2 +

44. The quantum numbers are:
2,0,0, + 1/2

45. 3. What are the four quantum numbers that represent an electron in 2 s orbital
d =2
f= 3
n = 2
ℓ= 0
mℓ= 0
ms= +½ -½

46. 4. What are the four quantum numbers that represent an electron in 3 p orbital
d =2
f= 3
n = 3
ℓ= 1
ms= +½ -½
mℓ= -1

47. 5. What are the four quantum numbers that represent an electron in 5 d orbital
ℓ= 2
mℓ=
ms= +½ -½

48. 6. What are the four quantum numbers that represent an electron in 4 f orbital
d =2
f= 3
n = 4
ℓ= 3
mℓ=
ms= +½ -½

49. 7. Where is an electron with the quantum numbers:
P = 1
d =2
f= 3
n = 4
mℓ = 0
ℓ = 2
ms = +½
4 d

50. 8. Where is an electron with the quantum numbers:
ℓ= 0
ms= -½
2 s2

51. s p
sharp
principal d f
diffuse
fundamental

52. 9. Assign quantum numbers for the tenth electron to fill a neon atom.
[He] 2s2 2p6
1s2 2s2 2p6 1 2 2 p p p s s

53. 10. Assign quantum numbers for the tenth electron to fill a neon atom.
1s2 2s2 2p6 1 2 2 p p p s s
Ml = 1
ms = - 1/2
n = 2
L = 1

54. Practice: MCQ Questions

55. 1
1) 1 2 )2 3) 3 4) 4

56. 2 1 2 3

57. 3 1 2 3

58. 4 1 2 3

59. 5 1 2 5 7

60. 6
Principle
Azimuthal
Magnetic
spin

61. 7
Principle
Azimuthal
Magnetic
spin

62. Principle
Azimuthal
Magnetic
spin

63. 9
orbitals
Wave functions
nodes
null points

64. 10
1) n 2) l 3) ml 4) ms

65. 11
1) Aufbau Principle 2) Pauli Exclusion Principle 3) Heisenberg Uncertainty Principle 4) Mendeleev’s Priciple

66. End of the show !!!

67. n l ml
Number of orbitals
Orbital Name
Number of electrons 1 1s 2 2s
-1, 0, +1 3 2p 6 3s 3p
-2, -1, 0, +1, +2 5 3d 10 4 4s 4p 4d
-3, -2, -1, 0, +1, +2, +3 7 4f 14