Electron Configuration (Gr. 8 Science)

1. ELECTRON CONFIGURATIONS
and
QUANTUM NUMBERS
Tony Coloma
Gr. 8

5. Memory Device to Remember the Order of Orbitals
1s,
2s, 2p,
3s, 3p,
4s, 3d, 4p,
5s, 4d, 5p, 6s,
4f, 5d, 6p, 7s, 5f…
Remember this!

6. Guide
• THE AUFBAU
PRINCIPLE (Building
up principle): Electrons
are added to atomic
orbitals starting with the
lowest energy orbital and
building up to higher
energy orbitals.

7. Guide
• PAULI
EXCLUSION
PRINCIPLE: Only 2
electrons can
occupy an orbital
and they must have
opposite spins.

8. Guide
• HUND’S RULE:
Electrons occupy
orbitals in a
sublevel one at a
time until each
orbital has 1 e-.
They will not
double up until
each orbital has
at least one
electron

9. Main Energy Level
(n)
(sometimes called
a “Shell”)
Sub-shells*
are
represente
d by:
Number of
orbitals**
per sub-
shell
Max Number of
e-
per
sub-shell
1 (K-Shell) s s = 1 s = 2 e-
2 (L-Shell) s, p s = 1
p = 3
s = 2 e-
p = 6 e-
3 (M-Shell) s, p, d s = 1
p = 3
d = 5
s = 2 e-
p = 6 e-
d = 10 e-
4 (N-Shell) s, p, d, f s = 1
p = 3
d = 5
f = 7
s = 2 e-
p = 6 e-
d = 10 e-
f = 14 e-
*sub-shells
s = Sharp
p = Principal
d = Diffuse
f = Fundamental
**The 3-dimensional region
around the nucleus where the
probability of finding electrons are
maximum are called orbitals.
2
1
3
4
K
L
M
N
s s s s
p p
d
p
d
f

11. 2
1
3
4
K
L
M
N
s s s s
p p
d
p
d
f

13. QUANTUM NUMBERS
1- PRINCIPAL QUANTUM NUMBER (n).
Designates the main energy level or shell.
2- ANGULAR MOMENTUM QUANTUM
NUMBER (l). Designates the sub-level
where the electron can be found.
Gives the SHAPE OF THE ORBITALS
3- MAGNETIC QUANTUM NUMBER (ml). Specifies to
which orbital within a subshell the electron is
assigned
s subshell: ml = 0
p subshell: ml = -1, 0, 1
d subshell: ml = -2, -1, 0, 1, 2
f subshell: ml = -3, -2, -1, 0, 1, 2, 3
4- SPIN QUANTUM NUMBER (ms). Designates the
SPIN OF THE ELECTRON (describes the behavior of
the e-, not the location).
 Values: +½ , -½
 Arrow up ↑ is +½, arrow down ↓ is –½

14. 17Cl: 1s22s22p63s23p5
Condense: [Ne] 3s² 3p⁵

15. -1 0 1
-1 0 1
-1 0 1
-2 -1 0 1 2
-2 -1 0 1 2 -3 -2 -1 0 1 2 3
0
0
0
0
YOUR TURN

20. YOUR TURN

21. ELEMENT:
CONDENSED ELECTRON CONFIGURATION:
QUANTUM
NUMBERS
n
l
m
l
ms
ORBITAL
ENERGY
TEMPLATE