Bonding: Ionic, Metallic, & Covalent

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Bonding:
Ionic, Metallic,
& Covalent
Chemical Bonding-Focus Ionic!
Vocabulary

Chemical Bond

attractive force between atoms or ions that binds
them together as a unit

The type of bond is determined by how the
valence electrons are shared among the bonded
atoms

The energy required to break a bond = “Bond
Energy”
Vocabulary

Ionic Bond

Formed when valence electrons are completely
transferred from one atom to another.

Not a “real” bond, is an electrostatic attraction of
ions!!


Attraction between anions and cations
Occurs between metals and nonmetals – large
difference in electronegativity.
Valence
Electrons:
ELECTRONS
AVAILABLE FOR
BONDING
The Formation of Sodium Chloride
 Sodium has 1 valence electron
 Chlorine has 7 valence electrons
 An electron transferred gives
each an octet
Na: 1s22s22p63s1
Cl: 1s22s22p63s23p5
The Formation of Sodium Chloride
This transfer forms ions, each
with an octet:
Na+ 1s22s22p6
Cl- 1s22s22p63s23p6
Properties of Ionic Compounds
IONIC
Bond
Formation
Type of
Structure
Physical
State
e- are transferred from
metal to nonmetal
crystal lattice
solid
Melting
Point
high
Solubility in
Water
yes
Electrical
Conductivity
yes
(solution or liquid)
Other
Properties
Ionic Bonding - Crystal Lattice
All salts are ionic compounds and form crystals
RETURN
Dot Notations – Period 2
Lewis dot notations for the valence electrons of
the elements of Period 2.
lithium
beryllium
boron
carbon
Li
Be
B
C
nitrogen
oxygen
fluorine
neon
N
O
F
Ne
Lewis Structures

Electron Dot Diagrams




X
show valence e- as dots
distribute dots like arrows
in an orbital diagram
4 sides = 1 s-orbital, 3 p-orbitals
EX: oxygen
2s
2p
O
Lewis Structures

Octet Rule


Most atoms form bonds in order to obtain 8
valence eFull energy level stability ~ Noble Gases
Ne
Lewis Structures & Bonding

Ionic – show transfer of e-
Ionic Boding!
RETURN
Lewis Structures & Bonding

Examples:

Al & Br

K&O
Lewis Structures & Bonding

Mg & N
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