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Report Sheet
Molecular Models
CHEM 110
LAST NAME
FIRST NAME
LOCKER #
DATE
LAB SECTION
Read the detailed procedure in the lab manual first, then construct the model
and, finally, answer the related questions given on this report sheet.
Part 1 – Bond Rotation and Conformers
1. Ethane: Name both conformations. Circle the conformation of lower energy.
H
HH
H
H
H H
H
H
H
H
H
2. 1,2-Dichloroethane:
SAMPLE – NOT FOR USE
Report sheet will be provided
at start of lab session
Complete the Newman projections for the eclipsed conformations, then circle the
conformation(s) with the lower energy.
Cl
H
Cl
H
H
Cl
H
non-equivalent
H
H
equivalent
Complete the Newman projections for the staggered conformations, then circle the
conformation(s) with the lower energy.
Cl
H
H
anti
IFS/05/11
Cl
H
Cl
H
H
H
gauche
MODa
2
3. Butane: What is the name of the following conformation? Circle the letter ((a) (b) (c) or (d)) of
your response:
HH
H
(a) Anti
THIS PART
OF REPORT
(b) Gauche
(c) Eclipsed
SHEET NOT
AVAILABLE
(d) Staggered
CH
CH
FOR
WEB VIEWING
3
H
3
Check () the position(s) where the above conformation would (could) be on the following
energy curve:

Potential Energy



SAMPLE – NOT FOR USE
Report sheet will be provided
at start of lab session



0o
60o
120o
180o
300o
240o
360o
Dihedral Angle
5. Cyclohexane: Draw the uppermost C-H bonds (at C1 and C4):
1
4
6. Cyclohexane: Draw the axial and equatorial hydrogen bonds on the chair conformers given
below:
5
5
1
3
1
3
7. Chlorocyclohexane: On each of the two chair conformers below, show the position of the
chlorine atom only (at carbon 1). Clearly label the Cl as axial (a) or equatorial (e). Circle the
more stable conformation. Then, for each conformer, use dash-line-wedge notation on the
accompanying sketch to indicate the position of the Cl atom relative to the ring.
Cl
5
6
5
3
IFS/05/11
1
1
4
Cl
5
1
2
6
3
3
5
1
4
2
3
MODa
3
THIS PART OF REPORT
Part 2 – Geometrical Isomerism
SHEET NOT AVAILABLE
1. Name the compound drawn below:  1-chloro-cis-2-butene
 1-chloro-trans-2-butene
FOR
WEB
VIEWING
CH2Cl
H
THIS PART OF
REPORT SHEET NOT
C
C
AVAILABLE
FOR
WEB VIEWING
Specify the configuration (E or Z) of the compound:
Is it possible to convert this to the other isomer without
breaking any bonds?
SAMPLE – NOT FOR USE
Report sheet will be provided
at start of lab session
H
CH3
2. Specify the configuration (E or Z) of the new compound:
Are all trans compounds assigned an E configuration?
3. For each alkene, circle the group (or atom) on each C of the double bond that has the higher
priority. Identify whether the geometry is E or Z by checking the appropriate choice.
THIS PART
CH(CH3OF
)2
REPORT SHEET NOT
C
C
 E or  Z
AVAILABLE
FOR
H WEB VIEWING
CH3
THIS
H
Cl PART OF
REPORT SHEET NOT
C
C
AVAILABLE
FOR
CH2CH3
H3CVIEWING
WEB
H3C
 E or  Z
5. Construct a model of the cis-3-methylcyclohexanol shown below. Complete the two chair
conformations, showing the position of the hydroxyl and methyl groups only. Do not include
the hydrogens. Clearly label the substituents as axial (a) or equatorial (e).
OH
THIS PART OF
REPORT
1 SHEET NOT
2
6
AVAILABLE
FOR
5
3
WEB
4 VIEWING
CH3
5
5
3
1
1
3
Part 3 – Optical Isomerism
1. Bromo-chloromethane: Are the two molecules of CH2ClBr superimposable? ___________
Is CH2ClBr chiral or achiral? _____________
2. Bromo-chloro-fluoromethane:
Are the two molecules of CHClBrF superimposable on each other? ___________
Assign an R or S configuration to each enantiomer:
H
H
 R or  S
C
Cl
IFS/05/11
Br
F
 R or  S
C
Br
F
Cl
MODa
4
(complete:)
Number of Chiral
Centres
(given)
(yes/no)
Sketch of Mirror
Image
Internal Plane of
Symmetry?
Sketch
(yes/no)
Compound
Is Mirror Image
Superimposable?
3, 4. Construct models of the following compounds, and then complete the table:
3.1 Glycine,
H OF
THIS PART
H2NCH2COOH
REPORT SHEET NOT
C FOR
AVAILABLE
COOH
COOH means:
WEBHVIEWING
NH2
C
C
O
 R or  S (check one,
if applicable)
HO
 R or  S (check one,
if applicable)
SAMPLE – NOT FOR USE
Report sheet will be provided
at start of lab session
3.2 Alanine,
H
CH3NH2CHCOOH
C
H3C
 R or  S (check one,
if applicable)
Cl
4.1 cis-1,2dichlorocyclopropane
3
C
COOH
NH2
2
 R or  S (check one,
if applicable)
Cl
1
 R or  S (check one,
if applicable, looking at
carbon 1)
1
2
3
 R or  S (check one, if
applicable, looking at
carbon 1)
Cl
3
THIS PART
OF
2
1
4.2 trans
-1,2REPORT
SHEET NOT
dichloroAVAILABLE FORCl
cyclopropane
WEB VIEWING
 R or  S (check one,
if applicable, looking at
carbon 1)
IFS/05/11
1
2
3
 R or  S (check one, if
applicable, looking at
carbon 1)
MODa
5
5. cis-3-methylcyclohexanol:
OH
6
5
1
4
How many chiral centres does it have?
Is there a plane of symmetry?
2
What is the R/S configuration at carbon 1?
3
SAMPLE – NOT FOR USE
Report sheet will be provided
at start of lab session
CH3
Use the dashed-line-wedge notation to depict the mirror image:
OH
6
5
1
4
What is the R/S configuration at carbon 1?
2
3
CH3
3 4 2 1
6. 3-fluorobutan-2-ol: CH3CHF-CH(OH)CH3. Fill in the blanks below:
Show the configuration (R or S) at carbons 2 & 3 on stereoisomers (b), (c) & (d) below:
THIS PART
H OF
OH NOT
REPORT SHEET
C
C
AVAILABLE
FOR
H
CH3
F VIEWING
WEB
H3C
H
CH3
HO
C
C
F
H3C
H
2S,3S
2___,3___
(a)
(b)
H
H
H3C
THIS
PARTOH
OF
C
C
REPORT
SHEET NOT
F
CH3
AVAILABLE
FOR
H
WEB VIEWING
CH3
HO
C
C
H
H3C
F
2___,3___
2___,3___
(c)
(d)
Give the letter (b, c or d) of one enantiomer of conformer (a):
Give the letters (a, b, d) of two diastereomers of conformer (c):
and
How many stereoisomers are possible for CH3CHF-CH(OH)CH3? ___________
How many pairs of enantiomers are there? ___________
Checkout:
IFS/05/11
Lab instructor’s initials:
MODa