1. Bonding and Formula Writing
Applied Chemistry

2. Valence electrons Electrons in the outmost energy level.
Outermost energy level is farthest from the nucleus.
Special stability if there are 8 valence e-’s.
This special stable arrangement is called a stable octet.
Noble Gases (Group VIIIA) are very stable & nonreactive because they form a stable octet.

3. Metals
Position in the Periodic Table: left of the staircase or diagonal
Lose electron(s) to form a stable octet.
Form positive ions called cations.

4. Nonmetals
Position in the periodic table right of the staircase or diagonal
Gain electron(s) to achieve a stable octet
Form negative ions called anions

5. Bonds: Force of attraction between 2 atoms
Covalent bond: forms between 2 nonmetallic atoms.
Share electrons.
Molecules contain covalent bonds
Molecular diatomic elements (7): H2, N2, O2, F2, Cl2, Br2, I2
Binary covalent molecules: Contain only 2 kinds of single atoms (2 different nonmetals).

6. Naming Covalent Compounds
1st element named in full
2nd element is shortened to ide ending
Mono 1
Hexa 6 Di 2
Hepta 7
Tri 3
Octa 8
Tetra 4
Nona 9
Penta 5
Deca 10

7. Examples of Covalent Compounds
CO carbon monoxide
CO2 carbon dioxide
NO2 nitrogen dioxide
SO3 sulfur trioxide
N2O4 dinitrogen tetroxide
H2O (dihydrogen monoxide) water
NH3 (nitrogen trihydride) ammonia
CH4 (carbon tetrahydride) methane
H2O2 (dihydrogen dioxide) peroxide

8. Ionic Bonds Formed between a metal and nonmetal Transfer of electrons
Ionic compounds contain ionic bonds
Binary ionic compounds contain only 2 kinds of ions (1 from a metal & 1 from a nonmetal) .

9. Writing Ionic Formula Example #1
Compound Name barium chloride
1st identify ion Ba+2 and Cl-1
2nd write formula BaCl2

10. Writing Ionic Formula Example #2
Compound name potassium carbide
1st identify ions K+ and C-4
2nd write formula K4C

11. Writing Ionic Formula Example #3
Compound name aluminum sulfide
1st identify ions Al+3 and S-2
2nd write formula Al2S3

12. Writing Ionic Formula Example #4
Compound name calcium nitride
1st identify ion Ca+2 and N-3
2nd write formula Ca3N2

13. Writing Ionic Formula Example #5
Compound Name zinc oxide
1st identify ions Zn+2 and O-2
2nd write formula ZnO

14. Practice with Ionic Compounds
Sodium sulfide Na2S
Barium phosphide Ba3P2
Zinc iodide ZnI2
Strontium nitride Sr3N2
Potassium chloride KCl
Barium chloride BaCl2
Lithium bromide LiBr
Sodium phosphide Na3P
Strontium chloride SrCl2
Silver Oxide Ag2O

15. Naming Ionic Compounds Example #1
Formula KCl
1st determine parts K = cation
Cl = anion
2nd locate anion chloride Cl-1
3rd locate cation potassium K+1
4th write name potassium chloride

16. Naming Ionic Compounds Example #2
Formula Sr3P2
1st determine parts Sr = cation
P = anion
2nd locate anion phosphide
3rd locate cation strontium
4th write name strontium phosphide

17. Naming Ionic Compounds Example #3
Formula AlCl3
1st determine parts Al = cation
Cl = anion
2nd locate anion chloride
3rd locate cation aluminum
4th write name aluminum chloride

18. Practice Naming Ionic Compounds
LiI lithium iodide
AlF3 aluminum fluoride
MgO magnesium oxide
BaF2 barium fluoride
Al2S3 aluminum sulfide
CaTe calcium telluride
Ag2S silver sulfide
Al2O3 aluminum oxide
Cs3N cesium nitride
MgBr2 magnesium bromide