Quantum Mechanics

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Quantum Mechanics
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• Can only refer to the probability of finding an
  e- in a region of space. Cannot specify the path
• 4 Quantum s are required to describe the energy
  of any electron in an atom (Pauli Exclusion
  Principle)
• No 2 e-s can have the same 4 s

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Quantum Mechanics

• Heisenberg Uncertainty Principle
• Impossible to know both the velocity and position
  of an electron at the same time

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1st Quantum Number (n)

• Given by the energy level
• n 1,2,3,4 to infinity
• Value of n is the main factor in determining the
  energy of an electron therefore, its average
  distance from the nucleus.

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2nd Quantum Number (l)

• Angular momentum
• Gives the sublevel (l)
• l n-1
• n1,2,3,4
• l 0,1,2,3
• Value of l 0 1 2 3
• letter s p d f

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Magnetic Quantum Number ( ml )

• Orientation of orbital
• Specifies the exact orbitalwithin each sublevel

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3rd Quantum Number (ml)

• Magnetic quantum number
• l0 s sublevel ml0 only one suborbital
• l1 p sublevel ml-1,0,1
• 3 suborbitals
• l2 d sublevel ml-2,-1,0,1,2
• 5 suborbitals
• l3 f sublevel m1-3,-2,-1,0,1,2,3
• 7 suborbitals

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4th Quantum Number (ms)

• Spin Number
• ½ or -1/2

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Feeling overwhelmed?
Read Section 4-2!
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For example

• Orbital Diagram

O 8e-