Transcript Quantum Numbers

Orbital Notation
Or “How to fill in orbital diagrams”
What is Orbital Notation
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Orbital notation is a visual transformation
of the electron configuration.
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Orbital notation shows you where each
specific electron is placed (in order) and
what it’s “spin” is.
Vocabulary List Check
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Pauli Exclusion Principle:
No two electrons in the same atom can have
the same spin quantum number. If one
electron has the value of +½ then the other
electron must have the value of −½.
In Orbital notation this means the arrows
representing the electrons must face
opposite direction (+ is up, - is down).
Vocabulary List Check
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Aufbau principle: (you already know
the concept)
Aufbau is the German word for “building
up.”
 The principle states that electrons fill
orbitals that have the lowest energy first.
 You fill electrons in a certain order.
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1s < 2s < 2p < 3s < 3p < 4s < 3d < 4p < 5s <
4d < 5p < 6s < 4f < 5d < 6p < 7s < 5f < 6d <
7p
Vocabulary List Check
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Hund’s Rule:
The rule that states that for an atom in the
ground state, the number of unpaired
electrons is the maximum possible and these
unpaired electrons have the same spin.
What?
You must share your electrons. “Everybody
gets one before anyone gets two.”
Meet your next reference sheet
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The orbital notation
reference sheet.
This shows each
orbital split apart into
its 3 dimensional
axes.
Relax, this is easy.
Write out the electron configuration
for Sodium
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Na, 11e1s22s22p63s1
We are now going to
represent each electron
as a ‘half arrow”.
We must fill in (build
up) the electrons as we
did previously but show
them using arrows on
the orbital notation
diagram.
First one in an orbital is
placed up (+½ spin)
Write out the electron configuration
for Boron
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B, 5e1s22s22p1
We are now going to
represent each electron
as a ‘half arrow”.
We must fill in (build
up) the electrons as we
did previously but show
them using arrows on
the orbital notation
diagram.
First one in an orbital is
placed up (+½ spin)
Write out the electron configuration
for Titanium
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Ti, 22e1s22s22p63s23p64s23d2
On your own. Calcium
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Ca, 20e1s22s22p63s23p64s2
Homework
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Complete the electron configuration/orbital
diagram worksheet.