Chem 321 Exam 2

eclipsing strain

deviation from ideal of SP3 (109°)

pair of non superimposable mirror images

a molecule that is non superimposable on its mirror image

achiral molecules with 2 or more stereogenic centers that is superimposable on its mirror image

molecule that is super imposable on its mirror image; often has plane of symmetry

a material that increases the rate of a reaction without being consumed by it

arrangement in space of the atoms in an enantiomer

a molecule that rotates plane polarized light

a molecule that rotates plane polarized light clockwise

a molecule that rotates plane polarized light counterclockwise

a 50:50 mixture of R/S enantiomers

molecules that are interconvertible through rotations about bonds within the molecule

molecules that have the same connectivity of constituents but different arrangements of their parts in space

the increase in energy caused by the deviation of an angle from the ideal demanded by hybridization

the destabilization induced in a molecule due to eclipsed bonds

strain caused by having elements too close together

• helicenes with ≥6 benzene rings
• Substituted biphenyl
• substitued allenes

contains even number of consecutive pi bonds

contains add number of consecutive pi bonds

torsional and some angular strain

2x #C = kcal/mol

decreases to cyclohexane

constantly increases as #H increases

planar

pucker

envelope and twist

chair, half chair, twist, boat

10.8 kcal/mol

5.5 kcal/mol

7 kcal/mol