Download Electron Configurations

Electron Configurations
• Write the orbital type and energy
level with superscripts for the
number of electrons they contain.
Electron Configurations
• Example: Carbon
Electron Configurations
• Need to Know:
• Period numbers of periodic
table are the energy levels (n)
of the orbitals
• Regions of periodic table where
certain “clouds” exist.
Electron Configurations
• Example: Silicon
Si
Electron Configurations
• Start from Hydrogen and
work towards Silicon, filling
in all of the orbitals as you
progress…
Si
2
1s
2
2s
2p6 3s2 3p2
Electron Configurations
• For larger atoms change the
energy level for the d-block
and f-block.
• For the d you subtract 1.
• For the f you subtract 2.
Electron Configurations
• Example: Mercury (Hg) 80e• Starting from Hydrogen:
Hg
1s22s22p63s23p64s2 3d10 4p6 5s2 4d10 5p66s2 4f14 5d10
Noble Gas Configuration
• For elements with long
electron configurations, this
can shorten your answer.
• Noble Gases are located in
the final column on the
periodic table.
Noble Gas Configuration
• Example: W, atomic number
74
Noble Gas Configuration
• Work backwards from your
element to find the noble
gas that comes before it.
• For W, the noble gas before
it is Xe.
Noble Gas Configuration
• To start writing the
configuration:
 Xe 
 54 
Noble Gas Configuration
• Then, continue writing the
configuration like before,
starting from Xe.
• 6s24f145d4