2. What is Orbital NotationWhat is Orbital Notation
Orbital notation is a visual transformationOrbital notation is a visual transformation
of the electron configuration.of the electron configuration.
Orbital notation shows you where eachOrbital notation shows you where each
specific electron is placed (in order) andspecific electron is placed (in order) and
what it’s “spin” is.what it’s “spin” is.
3. Vocabulary List CheckVocabulary List Check
Pauli Exclusion Principle: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).
4. Vocabulary List CheckVocabulary List Check
Aufbau principle: (you already knowAufbau principle: (you already know
the concept)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.
11ss < 2< 2ss < 2< 2pp < 3< 3ss < 3< 3p < 4s < 3d < 4p < 5s <p < 4s < 3d < 4p < 5s <
4d < 5p < 6s < 4f < 5d < 6p < 7s < 5f < 6d <4d < 5p < 6s < 4f < 5d < 6p < 7s < 5f < 6d <
7p7p
5. Vocabulary List CheckVocabulary List Check
Hund’s Rule: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.”
6. What’s next?What’s next?
The orbital notationThe orbital notation
reference sheet.reference sheet.
This shows eachThis shows each
orbital split apart intoorbital split apart into
its 3 dimensionalits 3 dimensional
axes.axes.
Relax, this is easy.Relax, this is easy.
7. Write out the electron configurationWrite out the electron configuration
for Sodiumfor Sodium
Na, 11eNa, 11e--
1s1s22
2s2s22
2p2p66
3s3s11
We are now going toWe are now going to
represent each electronrepresent each electron
as a ‘half arrow”.as a ‘half arrow”.
We must fill in (buildWe must fill in (build
up) the electrons as weup) the electrons as we
did previously but showdid previously but show
them using arrows onthem using arrows on
the orbital notationthe orbital notation
diagram.diagram.
First one in an orbital isFirst one in an orbital is
placed up (+placed up (+½½ spin)spin)
8. Write out the electron configurationWrite out the electron configuration
for Boronfor Boron
B, 5eB, 5e--
1s1s22
2s2s22
2p2p11
We are now going toWe are now going to
represent each electronrepresent each electron
as a ‘half arrow”.as a ‘half arrow”.
We must fill in (buildWe must fill in (build
up) the electrons as weup) the electrons as we
did previously but showdid previously but show
them using arrows onthem using arrows on
the orbital notationthe orbital notation
diagram.diagram.
First one in an orbital isFirst one in an orbital is
placed up (+placed up (+½½ spin)spin)
9. Write out the electron configurationWrite out the electron configuration
for Titaniumfor Titanium
Ti, 22eTi, 22e--
1s1s22
2s2s22
2p2p66
3s3s22
3p3p66
3d3d22
4s4s22
10. On your own. CalciumOn your own. Calcium
Ca, 20eCa, 20e--
1s1s22
2s2s22
2p2p66
3s3s22
3p3p66
4s4s22