1. Atoms & Molecules

2. The atom

3. # neutrons = molar mass – atomic #
Examples
# protons = atomic #
# electrons = atomic #
If negative ion add extra electron(s)
If positive ion, subtract extra electron(s)
# neutrons = molar mass – atomic #

4. Show ONLY valence electrons!
Electron Dot Diagrams
Show ONLY valence electrons!
Fill up individual orbitals first, then pair up
Examples: Br, C, Mg, N

5. Held together by electrostatic attraction (+, -)
Ionic Bonding
Metal + Non Metal
Transfer of Electrons
Held together by electrostatic attraction (+, -)
Use “drop and cross” method to create compounds
Naming: begin with metal, end non metal with “ide”

6. Examples
Sodium Chloride
Lithium Sulfide

7. Molecular (COVALENT) Bonding
2 non metals
Share electrons, electrons attracted to nucleus of neighboring non-metal (still electrostatic attraction)
Naming: use prefixes, end in “ide”

8. Phosphorus trichloride
Examples
Carbon dioxide
Phosphorus trichloride