Chapter 4 Carbon and theMolecular Diversity of Life
Organic Chemistry The study of carbon compounds. Urea
Carbon’s versatility Forms 4 covalent bonds. Molecular shape is tetrahedral. Bonds easily to itself.
Major Elements Of Organic Molecules Carbon: +4 or -4 Hydrogen: +1 Oxygen: -2 Nitrogen: -3 The valences are the “rules” for building organic molecules.
Hydrocarbons Organic molecules made of only carbon and hydrogen.
Examples
Isomers Compounds with the same molecular formula but have different structures. Result: Different molecular and chemical properties.
Types Of Isomers Structural Geometric Enantiomers
Structural Isomers Different in covalent arrangements of their atoms. Butane Isobutane
Geometric Isomers Same covalent partnership but differ in spatial arrangements. Arise from the inflexibility of double bonds.
Enantiomers Molecules that are mirror images of each other. Usually involve an asymmetric carbon.
Comment Organisms are sensitive to even the most subtle variations in molecular architecture.
Example - Thalidomide Cells can distinguish between two isomers. One is an effective drug. The other causes birth defects.
Danielle AP Biology
Assignments Read Chapters 4, 5 in Campbell and/or Chapters 2,3 in Hillis Lab – graphing tips Homework 3 – Friday No broadcast Monday No lab next Tuesday, Thursday Homework 4 – Wednesday Thalidomide article – discussion posting due by Wed. next week.
Functional Groups A group of atoms attached to a carbon skeleton. Have consistent properties. Their number and kind give properties to the molecule.
Importance of Functional Groups
What to focus on: Structure of the functional group. Properties of the functional group. Examples of molecules with the functional group.
Aldehydes A carbonyl group at the end of a carbon skeleton. Ex. - C=O | H Sometimes written as - CHO
Ketones A carbonyl group in the middle of a carbon chain. Ex. -C-C-C- ||
Carboxylic Acids Donate H+ (acid). Form many weak organic acids.
Chapter Summary Be able to recognize isomers. Know the seven functional groups and what properties they give to molecules.