1. Chapter 6: Inorganic and Organic Compounds 6.5
Chem 1110
Figures: Basic Chemistry 3rd Ed., Timberlake and Timberlake

2. Ionic vs. Covalent Bonding
Ionic Bonding
Covalent Bonding
Metal - nonmetal (NaCl)
Electron transfer and electrostatic interactions
Formula Unit (from larger arrays)
Solids
Dissolve in water and conduct electricity
Two nonmetals (O2, H2O)
Electron sharing in bonds
Discrete molecules
All physical states (solid, liquid and gas)
If they dissolve in water, they do not conduct electricity

3. The Covalent Bond
Covalent Bonding: a chemical bond that results from two nuclei attracting the same shared electron pair

4. Forming a H2 Molecule
A covalent bond forms as two H atoms move close together to share electrons

5. Diatomic Elements
Several elements share electrons to form diatomic, covalent molecules:

6. Octet Rule Covalent compounds also obey the Octet Rule:
Each atom in the bond is seeking a noble gas configuration
Electrons are shared to achieve the octet
For Example:
Br → needs 1 electron to achieve an octet

7. Lewis Dot Structures
We can use Lewis Dot structures to help us form Covalent Bonds:
H with Cl
H with O
P with Br

8. Electron-Dot Formulas
the order of bonded atoms in a covalent compound
the bonding pairs of electrons between atoms
the unshared (lone) valence electrons
a central atom with an octet

9. Covalent Compounds

10. Bonding and Lone Pair Electrons
Bonding pair of electrons are shared to create the covalent bond
Non-bonding pair or lone pair make up the octet

11. Bonding and Lone Pair Electrons
Bonding pair of electrons are shared to create the covalent bond
Non-bonding pair or lone pair make up the octet
Cl2
HBr
H2S

12. Naming Covalent Compounds
Most metallic atom comes first then the more negative + “-ide”
For Example: NO
NO2
N2O
Name includes the total number of each atom:
Table 6.10 (p. 178)

13. Naming Covalent Compounds
For Example: SiBr4 P4O10

14. Naming Covalent Compounds
Many covalent compounds have common names that you are most likely familiar with:
NH3
H2O
H2S
CH4

15. Formulas and Names of Some Covalent Compounds

16. Learning Check Select the correct name for each compound:
A. SiCl4 1) silicon chloride
2) tetrasilicon chloride
3) silicon tetrachloride
B. P2O5 1) phosphorus oxide
2) phosphorus pentoxide
3) diphosphorus pentoxide
C. Cl2O7 1) dichlorine heptoxide
2) dichlorine oxide
3) chlorine heptoxide

17. Learning Check Write the name of each covalent compound:
PCl3 _____________________
CCl4 _____________________
N2O _____________________