1. Molecular Names and Formulas (Covalent Compounds)

2. Carbon and oxygen combine to form
carbon monoxide (CO) and carbon dioxide (CO2), but these two invisible gases are very different.
Carbon monoxide is an invisible, gaseous compound of carbon and oxygen. It is a toxic product of incomplete burning, such as occurs in automobile engines and faulty furnaces.

3. A prefix tells how many atoms of each element are present in one molecule.
Number
mono- 1
hexa- 6
di- 2
hepta- 7
tri- 3
octa- 8
tetra- 4
nona- 9
penta- 5
deca- 10
carbon monoxide (CO)
carbon dioxide (CO2)

4. CCl4 SO3 H2O N2O Molecular Naming Rules:
Name elements in formula order.
Prefixes show the number of each atom.
Suffix of last element is –ide.
No prefix mono- for first element.
N2O
di mon
nitrogen oxygen
ide
CCl4
SO3
H2O
carbon
tetrachloride
sulfur
trioxide
dihydrogen
monoxide

5. 1. Which of the following compounds is named INCORRECTLY?
Quick Quiz!
1. Which of the following compounds is named INCORRECTLY?
CS2 carbon disulfide
BCl3 boron trichloride
IF7 iodine heptafluoride
PCl5 phosphorus hexachloride

6. 2. Which of the following molecular compounds is named INCORRECTLY?
Quick Quiz.
2. Which of the following molecular compounds is named INCORRECTLY?
PCl3 phosphorus trichloride
C2O5 dicarbon pentoxide
CF4 carbon tetrafluoride
H3P hydrogen monophosphide

7. 3. The correct formula for hexaphosphorus trisulfide is P7S3 S3P6 P6S3
Quick Quiz.
3. The correct formula for
hexaphosphorus trisulfide is
P7S3
S3P6
P6S3
S3P7

8. Prefix Number mono- 1 hexa- 6 di- 2 hepta- 7 tri- 3 octa- 8 tetra- 4
A prefix tells how many atoms of each element are present in one molecule.
Prefix
Number
mono- 1
hexa- 6
di- 2
hepta- 7
tri- 3
octa- 8
tetra- 4
nona- 9
penta- 5
deca- 10