Periodic Properties Of The Elements
ADVERTISEMENT
1
2
3
4Periodic Properties of the Elements
(Chapter 8)
Electronic Configurations
1. The Aufbau Principle --
Order of Filling Subshells
atomic # = # protons = # electrons (in neutral atom)
add electrons to atomic orbitals, two per orbital, in the general order of
increasing principle quantum number n, for example:
#
Atom
Configuration
1s 1
1
H
1s 2
2
He
1s 2 2s 1
3
Li
1s 2 2s 2
4
Be
1s 2 2s 2 2p 1
5
B
1s 2 2s 2 2p 2
6
C
1s 2 2s 2 2p 3
7
N
1s 2 2s 2 2p 4
8
O
1s 2 2s 2 2p 5
9
F
1s 2 2s 2 2p 6
10
Ne
1s 2 2s 2 2p 6 3s 1
11
Na
2. Hund's Rule
(maximum # of unpaired electrons in orbitals of equal energy)
orbital diagrams:
↑↓
↑↓
↑
↑
C
1s
2s
2p
↑↓
↑↓
↑
↑
↑
N
1s
2s
2p
O ↑↓
↑↓
↑↓ ↑
↑
1s
2s
2p
Page 1
ADVERTISEMENT
0 votes
Related Articles
Related forms
Related Categories
Parent category: Education