Energy Level
(related to the
distance of the
nucleus)
Sublevel (related to
the shape)
# of orbitals in each
sublevel
Maximum # of
possible electrons
1
2
3
4
Rules for Electron Configuration:
Before we try electron configuration and orbital diagrams, there’s some
rules you need to know!
●
●
●
Aufbau Principle
○ Electrons are placed in orbitals of lowest energy first (s, p, d, f)
Pauli Exclusion Principle
○ If two electrons are sharing an orbital, they must have opposite
spins
○ We signify this by an up arrow (↑) and down arrow (↓)
Hund’s Rule
○ Within a sublevel (s, p, d, f), one electron must fill each orbital
first before they share an orbital
Hydrogen
●
How many electrons does Hydrogen have?
●
What is the electron configuration for Hydrogen?
●
What is the orbital diagram for Hydrogen?
●
Valence electrons are electrons in the highest energy level. What energy level
are Hydrogen’s valence electrons in?
●
How many valence electrons does Hydrogen have?
Helium
●
How many electrons does helium have?
●
What is the electron configuration for helium?
●
What is the orbital diagram for helium?
●
Valence electrons are electrons in the highest energy level. What energy level
are helium’s valence electrons in?
●
How many valence electrons does helium have?
Beryllium
●
How many electrons does Beryllium have?
●
What is the electron configuration for Beryllium?
●
What is the orbital diagram for Beryllium?
●
Valence electrons are electrons in the highest energy level. What energy level
are Beryllium’s valence electrons in?
●
How many valence electrons does Beryllium have?
Nitrogen
●
How many electrons does nitrogen have?
●
What is the electron configuration for nitrogen?
●
What is the orbital diagram for nitrogen?
●
Valence electrons are electrons in the highest energy level. What energy level
are nitrogen’s valence electrons in?
●
How many valence electrons does nitrogen have?
Slides 17 and 18: Sodium
●
How many electrons does sodium have?
●
What is the electron configuration for sodium?
●
What is the orbital diagram for sodium?
●
Valence electrons are electrons in the highest energy level. What energy level
are sodium’s valence electrons in?
●
How many valence electrons does sodium have?