Quantum Theory

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Quantum Theory

• Beyond Bohr

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What we know from Bohr

• Bohr came up with the (at the time) radical idea
  that electrons orbit around the nucleus.
• He said that energy could only change in little
  jumps (quantas) which led us to Quantum
  Mechanics

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Quantum Mechanical Model

• There are four quantum numbers

Principle Quantum Number (n) Describes the location of the electron represent the energy level of the electron -- From n1, 2, 3, 4.
Azimuthal Quantum Number (l) Also describes an electrons location more specifically the orbital where the electron is -- From l 0, 1, 2, 3
Magnetic Quantum Number (ml) Describes the electrons location within the orbital. -- From l to l
Spin Quantum Number (ms) Describes the spin of the electrons in the orbital. -- 1/2 or -1/2
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Azimuthal Quantum Number

• l 0 describes an s-orbital

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p-orbitals

• l 1describes the p-orbitals
• There are 3 p-orbitals.

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d-orbitals

• l 2 describes the
• d-orbitals
• There are 5 d-orbitals

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f-orbitals

• l 3 describes the f-orbital
• There are 7 f-orbitals

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So how does Quantum Theory Work?

• An electrons position can be determined if the
  quantum numbers are known.
• For example
• Where is an electron with the following quantum
  numbers located?
• - n2, l1, ml1

Answer 2p orbital, 3rd space
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So what else can you do with it?

• You can count the electrons in an atombeyond the
  usual 3 orbitals (or 18 electrons)

Orbital Maximum Number of electrons
s 2
p 6
d 10
f 14
s-orbitals are at all energy levels.
p-orbitals begin at n2
d-orbitals begin at n3, f-orbitals begin at n4
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Orbitals - according to energy