1. Hydrocarbon Names Saturated hydrocarbons (alkanes) have general formula C n H 2n+2 CH 4 methane C 2 H 6 ethane C 3 H 8 propane C 4 H 10 butane C 5 H 12 pentane C 6 H 14 hexane C 7 H 16 heptane C 8 H 18 octane C 9 H 20 nonane C 10 H 22 decane Nonpolar bonds, only London dispersion forces

2. Acid Names All acid formulas start with H Binary acid names start with “hydro”, change root ending to “ic” and add “acid”. HCl hydrochloric acid HCN hydrocyanic acid HBr HI

3. Acid Names Binary acids are only named as acids when in water solution. Dry compounds are named as molecular compounds Example: HCl is hydrochloric acid in water solution, but hydrogen chloride as a free gas

4. Ternary acid names Use root of anion name followed by “-ic” or “-ous” and “acid” “-ic” is used with anions ending in “-ate” and “-ous” is used for “-ite”. H 2 SO 4 sulfuric acid H 3 PO 4 HNO 3 HClO 2

5. Exceptions to Octet rule Odd electron molecules (ex. NO 2 ) Electron deficient molecules (ex. BF 3 ) Expanded octet - only for period 3 and higher (ex. SF 6, PCl 5, SO 4 -2 )

6. Bond Polarity Bonds are polar when there is an unequal distribution of electrons in a bond

7. Bond Polarity Polar bonds are formed when two atoms of unequal electronegativity are bonded The bond has a “dipole moment” because of the  + and  - poles

8. Bond polarity EN difference of 0-0.4: nonpolar covalent EN difference of >0.4-1.4: polar covalent EN difference of >1.4: ionic bond Greater dipole-dipole interactions means greater mp and bp Example: propane (C 3 H 8, 44amu) has boiling point -42ºC, dimethyl ether (CH 3 OCH 3, 46amu) has bp -23ºC

9. Molecular geometry VSEPR = valence shell electron pair repulsion Bonding and nonbonding pairs will arrange themselves around an atom so that they are as far from each other as possible 2 pairs - BeCl 2 Linear geometry, bond angle = 180º

10. Molecular geometry Three pairs - BH 3, CH 2 O Trigonal planar geometry, bond angle 120º Four pairs - CH 4 Tetrahedral geometry, bond angle = 109.5º Five pairs - PCl 5 (expanded octet) Trigonal bipyramid geometry, bond angles = 120º and 90º

11. Molecular geometry Six pairs - SF 6 Octahedral geometry, bond angles 90º Nonbonding Pairs Two bonding, one nonbonding - NO 2 - Bent geometry (anything with two bonding pairs and at least one nonbonding pair) Bond angle <120º, since nonbonding pair is larger

12. Molecular geometry Three bonding, one nonbonding (NH 3 ) Trigonal pyramidal geometry, <109.5º bond angle Hybridization Recombination of s and p orbitals to produce equivalent bonding orbitals Two atoms and/or lone pairs: sp hybridization

13. Hybridization Three atoms and/or lone pr.: sp 2 Four atoms and/or lone pr.: sp 3