This document provides information on the electron configuration and arrangement of electrons in atoms. It shows the proton and neutron makeup of elements from helium to aluminum. It then illustrates the electron configuration using shorthand notation for elements oxygen through sodium. The rest of the document defines quantum numbers such as principal energy level, azimuthal, magnetic, electron spin, and how they relate to the shape and orientation of atomic orbitals in an atom.

3. proton Shell
+
N
-
+
- N
electron neutron

4. He Li
Li shorthand
2p+ 3 p+ 3 p+ 2e– 1e–
2 n0 4 n0 4 n0

5. Be B
Al
4 p+ 5 p+ 13 p+
5 n° 6 n° 14 n°
O Na
8 p+ 2e– 6e– 11 p+ 2e– 8e– 1e–
8 n° 12 n°

6. • He proposed that electron behaves
like a wave, specifically a standing
wave. A standing wave is a wave
that does not travel down its medium.
• A standing wave is obtained when one
point (called the node) in the middle
of the wave is stationary.

7. • UNCERTAINTY PRINCIPLE
• States that there is NO way to determine
both the precise location and momentum
(mass X velocity) of small particles at the
same time.
• Principle implies that if we could measure
the momentum of an electron
accurately, we could NOT determine its
location at the same time.

13. • Corresponds to the
energy level
numbers. As (n)
increases, the average
+
N
distance of an electron K L M
from the nucleus also N
+
increases. n=1
• The larger the (n) the n=2
larger the atomic n=3
orbital. n= so on…

14. • AZIMUTHAL
• The sublevels that
describes the shape of
the atomic orbitals.
+
N
K L M
• Examples: +
N
=0 s orbital
n=1
=1 p orbital n=2
=0 d orbital n=3
=1 f orbital n= so on…

15. PRINCIPAL POSSIBLE
ENERGY LEVEL (n – 1) VALUES: SUBLEVELS
(n) 0 TO (n – 1)
1 1–1=0 0 s
2 2–1=1 0,1 s,p
3 3–1=2 0,1,2 s,p,d
4 4–1=3 0,1,2,3 s,p,d,f
5 5–1=4 0,1,2,3,4 s,p,d,f,g
6 6–1=5 0,1,2,3,4,5 s,p,d,f,g,h

16. • Describes the orientation
of the atomic orbital in
space. The magnetic quantum
number can only have (2 X 1)
integral values for a particular .
+
N
• Example: K L M
N
+
=1
n=1
[ (2 X 1) + 3] or 3 m
n=2
Values. These 3 m values n=3
are -1, 0, and +1
n= so on…

17. Number of
SUBLEVEL 2 + 1 m VALUES Atomic Orbital
1 0 1s 2(0) + = 1 0 1
2 0 2s 2(0) + = 1 0 1
3 1 2p 2(1) + = 3 1, 0, -1 3
0 3s 2(0) + = 1 0 1
1 3p 2(1) + = 3 1, 0, -1 3
2 3d 2(2) + = 5 2, 1, 0, -1, -2 5

18. • Describes the spin
direction of an electron.
There are only two
possible values for the
+
electron spin quantum N
K L M
number, and these are + N
+
½ and – ½.
n=1
• ms = + ½ (clockwise)
n=2
• ms = - ½ (counter- n=3
clockwise)
n= so on…

20. • Wolfgang Pauli
• States that no two electron can be described by
the same four quantum numbers.
• Two electrons may have the same first three
quantum numbers ( ) but these two
electrons must have different spins
•

21. • Principle applies the laws in QUANTUM MECHANICS
to the distribution of electrons among energy levels
in the ground states (most stable states) of atoms.
• The word AUFBAU means “building up” in
german.
•

24. E
4d
N 5s
4p
E 4s
3d
3p
R 3s
2p
G 2s
1s
Y

25. 2 ways of
spdf notation
writing for H, atomic # = 1
configs. 1 # of e
One is 1s
called the
spdf
notation. value of l
value of n

32. Electron Arrangement in Atoms
Electrons in atoms are arranged as:
SHELLS (n)
SUBSHELLS (l)
ORBITALS (ml)