This is a brief presentation outlining the three ways to draw electron configurations--using the periodic table, using the visual mnemonic, and using the ear memory.

1. Writing Electron Configurations
Three ways to do it

2. First, a clever look at the atom
Atom NOVA

3. The Way That Almost Forced Me from
Chemistry
Actually, it's
not so bad,
and millions
find it their
favorite
method.
Try it with Na, Cl
and Fe. . .
Aufbau rule: electrons always occupy the lowest
energy level available. Find it on this diagram.

4. The Periodic Table Method
n
1
2
3
4
5
6
7
s
p
n-1
d
f
From U.Cal Davis
n-2

5. The Verbal Memory Method

This takes a while, but it's a good check on the
other methods

Memorize

1s2 2s2 2p6 3s2
3p6
4s2
3d10 4p6

6. Exceptions

There is a “pull” toward half-filled and
completely filled degenerate orbitals: lower
energy state than the alternative

Example: 4s2 and 3d9 vs 4s1 and 3d10

This works with ions as well: explains Ag+


Always think: what if we took one, two or three
electrons away from this atom
And, what if we add electrons to this nonmetal

7. Exceptions

There is a “pull” toward half-filled and
completely filled degenerate orbitals: lower
energy state than the alternative

Example: 4s2 and 3d9 vs 4s1 and 3d10

This works with ions as well: explains Ag+


Always think: what if we took one, two or three
electrons away from this atom
And, what if we add electrons to this nonmetal