Covalent Molecular Compounds
Objectives:
• Write chemical formulas
for covalent molecular
compounds
• Name covalent molecular
compounds
What is a Molecular Compound
• Compounds that are formed
from 2 non-metals
NOTE
• Sets of non-metals can form
more than 1 compound so we
and O canmethod
form of
need C
a different
CO or CO
2 naming
writing formulas
and
compounds
Prefix System
• Valence Numbers are not used
• A prefix tells how many atoms
of each element are in the
molecule
• The prefix is NOT crossed
• The second non-metal ends in
“ide”
The Prefixes
EXAMPLE
• Carbon Dioxide
NOTE: Mono is used only
on the second non-metal if
necessary
CO2
EXAMPLE
• Carbon Monoxide
NOTE: Mono is used only
on the second non-metal if
necessary
CO
EXAMPLE
• Phosphorus Trichloride
PCl3
EXAMPLE
• Sulfur Hexafluoride
SF6
EXAMPLE
• Dinitrogen Monoxide
N 2O
Naming Covalent Molecular Compounds
• Name the prefix for the
FIRST subscript
Mono is only used
• Name first element
for the second
• Name the
prefix
for
the
non-metal
SECOND subscript
• Name second element
• Add “ide”
• OF2
EXAMPLE
Oxygen Difluoride
• Cl2O8
EXAMPLE
Dichlorine Octoxide
• S2Cl2
EXAMPLE
Disulfur Dichloride
• CBr4
EXAMPLE
Carbon Tetrabromide
• P2O3
EXAMPLE
Diphosphorus Trioxide
Page 167 #64, 66