Support Materials:

Hyperlinks provide FYI pages.

•  Goal:
  To define and characterize the properties of small molecules.
   
•  Objectives: Students will be able to...
   
  • determine the oxidation number of C in various food and drug substrates.
    Comprehension: Know how to assign electrons to atoms based on differences in electronegativity. Examples: O, N are more electronegative than C. C is more electronegative than H.
     
    • determine whether an oxidation or reduction has occurred in a chemical reaction.
      Applications:
      1) Living systems oxidize (combust) foods to make ATP.
      2) An oxidative reaction may result in drug toxicity (i.e., oxidation of a large dose of acetaminophen (Tylenol) results in liver damage)
      3) Antioxidants are sources of electrons - In effect, antioxidants are chemicals that strongly inhibit oxidative reactions (examples include 3,4-dihydroxybenzoic acid - found in many edible fruits and vegetables, and in wines - and a-tocopherol, or vitamin E).
       
  • count the number of valence electrons for different atoms in a compound.
    Comprehension: Know how to draw structural formulas that show both bonding and nonbonding electron pairs (Lewis structures).
    Applications:
    1) Predict molecular geometry: For example, water is a bent or V-shaped molecule, but carbon dioxide (which also has 3 atoms) is linear. Why? Bicarbonate ion is trigonal planar. Ammonia is trigonal pyramidal. Methane is tetrahedral.
    2) Predict whether an atom has a positive or negative charge. (See Chapter 2 for Applications). Know how to predict charge when give a structural formula in which the charge has been deliberately omitted: Convert the structural formula to a Lewis structure by adding enough electron pairs to each atom (C, N, O) so that it satisfies the octet rule. Now count valence electrons and compare with the periodic table value for valence number. I gave two examples in class: coniine and Dettol.
     
  • identify and name the organic functional groups in a compound.
    Application: Aspartame - also called NutraSweet: produces methanol, CH₃OH, when metabolized. Is methanol poisoning likely to be the reason for all the "victim awareness" groups on the web? - More in Chapter 3.