1. Covalent Nomenclature

2. Naming Molecules
Covalent compounds are named using prefixes to designate the number of atoms in the molecule.
Example:
N2O4
Dinitrogen tetraoxide
Prefix needed if first
Element is more than
One atom
+ name of element
Prefix indicating
# of atoms
+ root name of
Element + ide

3. PREFIXES CCl4 As2O3 CO SO2 NF3 # of atoms Prefix 1 Mono- 2 Di- 3 Tri-
Tetra- 5
Penta- 6
Hexa- 7
Hepta- 8
Octa- 9
Nona- 10
Deca-
Name the following compounds:
CCl4
As2O3 CO
SO2
NF3

4. Types of covalent bonds
POLAR VS. NON-POLAR
Types of covalent bonds

5. Electronegativity The ability of an atom to attract electrons.
Each element on the periodic table has a specific electronegativity value.

6. Non-Polar Covalent Bonds
A covalent bond in which the bonding electrons are shared equally.
When atoms have difference in electronegativities.
Examples: H-B, Cl-Cl, Cl-Br

7. Polar Covalent Bonds
Occur when there is an unequal sharing of electrons between atoms in a covalent bond.
When atoms have difference in electronegativities.
Examples: H-O, C-O, C-Cl

8. Partial Charge Indicate which atom is more electronegative.
Show where the electrons reside more.

9. PRACTICE
1. Predict the type of bond that will form between the following atoms:
C and Se
C and H
Na and S
N and N
Li and O
B and O

10. Identify the bond types and the label the partial charges for the following molecules:
N2 C2H4 SF2