Name ______________________________________________________ Period ___________________
Chapter 7/9: Nomenclature & Properties
Keller/Rosenzweig
Naming Binary Covalent (Molecular) Compounds
REVIEWQUESTION: What is the difference between an ionic compound and a covalent compound?
1. Name covalent compounds using the following rules:
1. Name the first element listed in the compound with the prefix indicating how many atoms of that
element exist in the compound
2. Name the second element listed in the compound using the prefix indicating how many atoms of that
element exist in the compound
3. Change the ending of the second element to “ide”
4. **If there is only one atom of the first element, DO NOT use a prefix
mono
di
tri
tetra
penta
1
2
3
4
5
hexa
hepta
octa
nona
deca
a. C3Cl6
c. C5F10
b. Si2O7
d. PCl5
6
7
8
9
10
2. Write the formula for the following covalent compounds using the following rules:
1. Look at the first word of the compound name to identify the element
2. If the first word of the compound name has a prefix, write the number that the prefix represents as the
subscript of that element
3. If the first word of the compound name does not have a prefix, assume there is only one atom of that
element and no subscript is needed
4. Look at the second word of the compound name to identify the second element
5. Write the number that the prefix represents of the second word in the compound name as the subscript
of the second element
6. Do NOT criss cross!
7. Do NOT reduce subscripts!
a. dichlorine monoxide
c. carbon tetrafluoride
c. tetracarbon octabromide
d. dinitrogen pentoxide
Try: Either write the formula or name the following covalent compounds using the outlined rules.
carbon dioxide
diphosphorus pentoxide
carbon dioxide
sulfur trioxide
oxygen difuoride
nitrogen monoxide
dinitrogen tetroxide
N2 O
CCl4
C3I8
CS2
PBr3
P2O5
CO