Chemical Bonding Chemical Bonds • Compound are formed from chemically bound atoms or ions • Bonding only involves the valence electrons Chemical Bonds • Defn – force.

Download Report

Transcript Chemical Bonding Chemical Bonds • Compound are formed from chemically bound atoms or ions • Bonding only involves the valence electrons Chemical Bonds • Defn – force.

Chemical Bonding
Chemical Bonds
• Compound are formed from chemically
bound atoms or ions
• Bonding only involves the valence
electrons
Chemical Bonds
• Defn – force holding two atoms together
• How are they formed?
Atoms gain, lose, or share valence
electrons
• Why does bonding occur?
Stability – achieve octet rule
Covalent Bonding
Covalent Bond
• Defn – two atoms share one pair of
electrons
A•
•B
A •• B
Electrons
shared
Covalent Bonds
• Where are these bonds found?
- molecules (molecular compounds)
- polyatomic ions
Covalent Bonding
• What’s going on? Sharing of electrons
• Molecule – formed when 2 or more atoms
bond covalently
Covalent Bonding Properties
Bond Formation
Electrons are shared between two
nonmetal atoms
Type of Structure
True molecules
Physical State
Liquid or gas, brittle solids
Melting Point
Low
Solubility in Water
Usually not
Electrical Conductivity
No
Naming Covalent Compounds
• Prefix System (binary compounds)
1. Less e-neg atom
comes first.
2. Add prefixes to indicate # of atoms. Omit
mono- prefix on first element.
3. Change the ending of the
second element to -ide.
C. Molecular Nomenclature
PREFIX
monoditritetrapentahexaheptaoctanonadeca-
NUMBER
1
2
3
4
5
6
7
8
9
10
Covalent Compound Names
z CCl4
carbon tetrachloride
z N 2O
dinitrogen monoxide
z SF6
sulfur hexafluoride
Covalent Formulas
z arsenic trichloride
AsCl3
z dinitrogen pentoxide
N2O5
z tetraphosphorus decoxide
P4O10