1. CH 6 Chemical Bonding 6.1 Into to chemical bonding
Ionic bonding: cations and anions
Covalent bonding: share e-
Non-polar covalent: share e- equally
Polar covalent: uneven sharing of e-

2. 6.2 Covalent Bonding and Molecular Compounds
Chemical formula: numbers of atoms of each kind in a chemical compound, uses atomic symbol and subscript
Molecular formula: types and numbers of atoms combined in single molecule of molecular compound
Covalent Bonds:
Attracted and repelled
Affected by distance

3. Bond Length Octet Rule Avg distance between them at minimum PE
Bond energy; E required to break bond; kJ/mol
Octet Rule
Noble gases stable b/c full 8e- in outer shell (s&p)
By gaining/losing/sharing e- atoms get full octet
Exceptions: H (2e-), B (6e-), BF3, F/O/S (over 8e-)

4. 6.3Ionic Bonding and Ionic Compounds
Ionic bonding: cation and anion make neutral compound
Formula unit: collection of atoms that an ionic compound can be written
Electron-dot can help show bonds of ionic compounds

5. Crystal Lattice Lattice Energy
Ions minimize PE by combining in organized arrangement
Lattice Energy
E released when 1mol of ionic crystalline compound is formed from gaseous ions
Negative is E given off

6. Polyatomic Ions: charged group of covalently bonded atoms
Ionic Properties:
Molecular compounds: Forces of attraction not strong lower melting pt; Many even gases at room temp
Ionic compounds: strong attractive forces  higher melting/boiling pts; hard but brittle; molten state are electrical conductors
Polyatomic Ions: charged group of covalently bonded atoms

7. 6.4 Metallic Bonding Attraction of metal atoms and surrounding e-
Highest energy levels occupied by few e-
Outer energy levels overlap and allow e- join

8. Metallic Properties: Bond Strength:
Freedom of e-  high electrical/thermal conductivity
Strong absorbers/reflectors of light
Many orbitals separated by little space allows for absorbing light frequencies; move e- higher E orbital
e- drops back/reradiated, so accounts luster
Malleable: shaped/ thin sheets
Ductility: drawn/pulled into wires
Bond Strength:
Varies with charge
Heat of vaporization: amount of E to break bonds

9. 6.5 Molecular Geometry
VSPER Theory: repulsion of sets of valence e- surrounding atom causes them to be as far apart as possible
Unshared e- pairs will still affect geometry (b/c negative charge will repel other e-)

11. Hybrid orbitals Dipoles
Equal energies created by combination of 2+ orbitals no same atom
Dipoles
Equal and opposite charges at a short distance

12. London- dispersion forces
H-bonding
H bonds to electronegative atom
London- dispersion forces
Intermolecular attractions from constant motion of e- creates instantaneous dipoles
Only forces acting on noble gases and nonpolar molecules