Organic Chemistry: Chapter 5 Stereochemistry Study Guide
Reading: 5.1 – 5.8; 5.10-5.12
Objectives: You should be able to:
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Turn molecules over or around mentally to compare them with one another to determine if they
are the same or not.
Manipulate bond line drawings, Newman projections, Fischer projections, Haworth projections,
and chair structures as needed to compare structures to see if they are the same, enantiomers,
diastereomers, or constitutional isomers.
Determine the relationship between sets of stereoisomers: enantiomers or diastereomers.
Determine if a molecule is chiral or achiral.
Determine if a molecule is meso.
Find all/any chirality centers in a molecule.
Determine the *possible* number of stereoisomers of a compound
(*know* the equation for determining the number of possible stereoisomers of a compound and
be prepared to use it)
Draw a mirror image of a molecule (and then determine if it is identical or an enantiomer).
Use your model kit as needed/necessary to do all of the above.
Determine whether compounds should have similar or different physical or chemical properties
after checking to see their relationship (different compound, constitutional isomers,
diastereomers, enantiomers)
Utilize the understanding of differences or similarities in physical properties of different
compounds to determine if they could be separated in various ways.
Convert from a “zig-zag” structure to a Fisher projection, and vice-versa
Be able to use Fisher projections to identify relationships between compounds – enantiomers,
diastereomers, same, constitutional isomers, etc., and to draw an enantiomer or diastereomer
for a given Fisher projection.
Know what optical activity means. Be able to tell whether a compound is optically active or not.
Determine the specific rotation for a particular stereoisomer, given the specific rotation of the
enantiomer of the compound.
Apply and interpret the following terms: scalemic, racemic, optically active, dextrorotary,
levorotary, specific rotation, measured rotation.
Determine the specific rotation for a racemic mixture
Utilize the equations below to calculate %ee, % major enantiomer, % minor enantiomer, specific
rotations for a mixture or a particular enantiomer, or the expected measured rotation, given the
appropriate starting information.
Equations for Polarimetry (you will be given all of these equations on the reference
page(s) – be prepared to use them as needed):
%ee = %major enantiomer - %minor enantiomer
%ee =

[ ]mix
*100%
[ ] pure
[ ] 

c *l