1. Write the formula for Lithium Nitride.
Agenda for Tuesday Jan 11th
Review/Practice Ionic Bonds
Metallic Bonds
Covalent bonds

2. Rules for writing Ionic formulas
The metal comes first (this does not include hydrogen), non-metal comes second.
Find the oxidation number of each element
The oxidation number of the metal becomes the subscript number of the non-metal and vise versa.
Lithium nitride:
Li1+ and N3- Li3N1 or Li3N

3. Rules for Naming Ionic formulas
Write the name of the positive ion (metal).
If you have a transition metal then you need to figure out its charge (remember the compound’s oxidation numbers must equal 0) and put it in roman numerals after the name; e.g. Copper (II). If it is not a transition metal proceed to step 3.
Write the root of the non-metal’s name (chlor- for chlorine, ox- for oxygen).
Add the ending –ide to the root.

4. Metallic Bonding Composed of closely packed cations
Valence e- are a “sea of electrons”
Attraction between valence e- and cations

5. Metallic Bonding
“sea of electrons” model explains physical properties of metals
Good conductors – e- flow freely
Ductile
malleable
luster

6. Covalent Bonding Nonmetal + nonmetal share electrons
Can share more than one pair (double, triple bond)
Atoms held together by sharing electrons are covalently bonded

7. Covalent (Molecular) Bonds
Properties
Molecules
Lower melting and boiling points
Most are liq or gas
Nonconductors
Start to talk about shapes
of molecules
Ammonia molecule

8. Multiple Bonds Double and triple covalent bonds
Sharing more than one pair of e-
Carbon dioxide
Nitrogen
Triple bonds are stronger than double bonds
More energy needed to break 3 bonds than 2 bonds

9. Polar and Nonpolar Covalent bonding can be:
Polar – electrons not shared equally
Nonpolar – electrons shared equally

10. Drawing Covalent Compounds
Draw Dot structure for each compound
Pair unpaired electrons of each compound
Draw a line where you paired electrons

11. Prefixes Number of atoms Prefix 1 Mono 6 Hexa 2 Di 7 Hepta 3 Tri 8
Octa 4
Tetra 9
Nona 5
Penta 10
Deca

12. Naming Covalent Compounds
1st word: Give the prefix designating the number of atoms of the first element present, then write the element’s name.
2nd word: Give the prefix designating the number of atoms of the second element present.
CO2: carbon di
Name the root of the second element.
CO2: carbon diox
Add –ide to the root of the second element.
CO2: carbon dioxide (official name)

13. Practice Dinitrogen Tetroxide N2O4 Phosphorus Pentachloride PCl5
CCl4
SCl2
Dinitrogen Tetroxide
Phosphorus Pentachloride
nitrogen monoxide
or nitrogen oxide
Carbon Tetrachloride
Sulfur Dichloride 13

14. More Practice Sulfur Hexafluoride Pentanitrogen Heptoxide
Diodine tetrachloride
Triastatine Octoxide
Phosphorous Mononitride
SF6
N5O7
I2Cl4
At3O8 PN

15. Bonding 100% ionic 100% covalent polar covalent ionic and covalent
NaCl NaNO Cl2
KBr Br2