chemical thermodynamics-- chapter13（chemical thermodynamics——chapter13）.doc

Organic Chemistry Polymers -- Chapter 21 (and 12.9) 1. Introductory Topics Bonding and Structure Concepts Review Chapters 9 and 10 (especially Lewis dot formulas, VSEPR, and Valence Bond Theory) Types of Chemical Formulas e.g., 2-propanol (iso-propanol) expanded formula condensed formula fully condensed formula (missing Cs and Hs are understood) ! ! ! Always FOUR BONDS to Carbon ! ! ! Structural Isomers - same chemical formula, but different arrangement (connectivity) of atoms e.g., C3H8O - 3 isomers (2 alcohols, 1 ether) 1-propanol 2-propanol ethyl methyl ether number of possible isomers can be very large, e.g.: C3H8 C4H10 C5H12 C6H14 C8H18 C10H22 C20H42 1 2 3 5 18 75 105  Optical Isomers (aka enantiomers) non-superimposable mirror images occur when four different groups are attached to a tetrahedral (sp3) carbon center, i.e., a chiral center all physical and most chemical properties are the same but enantiomers interact differently with other chiral molecules e.g., CH3CH(Br)Cl is chiral and exhibits enantiomers because its mirror images are not superimposable. In contrast, CH3CHCl2 is not chiral because it is superimposable on its mirror image. 2. Organic Functional Groups Tremendous Variety of organic molecular structures and properties are possible, e.g.: fortunately, the subject is very systematic ! and is readily classified by organic functional groups Organic Functional Groups Family Characteristic Structural Feature Examples Hydrocarbons Alkanes Alkenes Alkynes Aromatic only single bonds C=C C(C benzene ring CH3CH3 CH2=CH2 HC(CH Alcohols R-OH CH3CH2OH Ethers R-O-R CH3OCH3 Aldehydes Ketones Carboxylic Acids Esters Amines: 1( 2( 3( RNH2 RNHR RNRR CH3NH2 (CH3)2NH (CH3)3N Amides 3. Hydrocarbons (a) Alkanes CnH2n+2 CH4 methane C5H12 pentane C2H6 ethane C6H14 h