e.g., why is H2O different from H2S in acidity? in boiling point? in reactivity toward oxidizing agents?

e.g., why are thioesters less stabilized by resonance than are oxygen esters? how does this affect their biochemical properties?

e.g., why are biological molecules based on carbon, not silicon or germanium?

e.g., why is iron used as an oxidant in enzymes, while zinc is not?

e.g., what is electronegativity, and how does it vary going horizontally and vertically?


Students should be able to:

  1. write the electronic configurations of the elements in the first two horizontal rows, including the atomic orbitals involved

  2. reproduce the first two rows of the periodic table from memory, so they do not have to look it up constantly

  3. specify which are the metals, which are not



  1. What are the shapes of 1s, 2s, and 2p orbitals? Of 3d orbitals?

  2. What are the shapes and angles of hybrid orbitals? How are they constructed from simple atomic orbitals?

  3. Why do the electrons in an atom not simply fall into the nucleus?

  4. Why do atoms absorb light at only certain frequencies (or wave-lengths)?

Properties of Molecules


  1. What is the basis of covalent bonding?

  2. What are sigma bonds? Pi bonds?

  3. What is a bond energy?

  4. What are the approximate bond energies of a C-H bond? A C-C single bond? a C=C double bond?

  5. Which molecules can exist as cis/trans (Z/E) isomers?

  6. Which molecules can exist as enantiomers? As diastereomers?

  7. Which molecules will have dipole moments, and why?

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