(Use the following information for questions
1-2
.) Consider the molecule NH
2
Cl, chloroamine.
(1)
The
shape
of the molecule is
A.
tetrahedral
B.
trigonal planar
C.
pyramidal
D.
flat
E.
octahedral
(2)
The arrangement of electron pairs about the central N atom is
A.
tetrahedral
B.
trigonal planar
C.
pyramidal
D.
flat
E.
octahedral
(3)
Chloroamine (NH
2
Cl)
A.
has a strong bond dipoles and a net dipole moment.
B.
has no bond dipoles and a net overall dipole moment.
C.
has a strong bond dipoles and NO net overall dipole moment.
D.
has no bond dipoles bond dipoles and NO net dipole moment.
(4)
Which of the following substances is the
worst
Brønsted-Lowry acid?
A.
CH
4
B.
HCl
C.
HClO
3
D.
H
2
SO
4
E.
H
3
PO
4
(5)
Which element in CH
3
OCH
2
Li is the most electronegative?
A.
C
B.
H
C.
O
D.
Li
E.
H
3
(6)
Which of the following substances is the best Lewis acid?
A.
CH
3
CH
2
OH
B.
NH (CH
3
)
2
C.
H
2
O
D.
H
2
S
E.
BF
3
Matching (7 - 11)
Choose the structure that contains the listed functional group:
(7)
Alcohol
A.
B.
C.
D.
E.
(8)
Carboxylic acid
A.
B.
C.
D.
E.
(9)
Ethyl group
A.
B.
C.
D.
E.
(10)
Aldehyde
A.
B.
C.
D.
E.
(11)
Amide
A.
B.
C.
D.
E.
(12)
How many of the constitutional isomers of C
6
H
14
can be correctly named as "butane" using the IUPAC naming system?
A.
0
B.
1
C.
2
D.
3
E.
4
(Use the following information for questions 13-14.) Consider the following molecule:
(13)
Which of the following is true?
A.
A
is more stable than
B
due to reduced 1,3-diaxial
de
stabilization.
B.
B
is more stable than
A
due to reduced 1,3-diaxial
de
stabilization
C.
A
is more stable than
B
due to enhanced 1,3-diaxial stabilization
D.
B
is more stable than
A
due to enhanced 1,3-diaxial stabilization
E.
A
and
B
are exactly the SAME MOLECULE.
(14)
Which of the following statements is(are) correct?
A.
A
can be converted into
B
by a ring flip.
B.
A
can be converted into
B
by single rotation about a single bond.
C.
A
and
B
are exactly the SAME MOLECULE.
D.
Both
a
and
b
are correct.
E.
None of these is correct.
(15)
Consider the conformers of pentane defined by rotation about the C2—C3 bond axis. Which of the following Newman projections represents the
lowest
energy minima?
A.
B.
C.
D.
E.
both a and b
(16)
Ring strain is very high for cyclopropane. The best explanation for this is
A.
Smaller bond angles produce increased eclipsing interactions.
B.
The molecules are deficient in H compared to non-cyclic alkanes.
C.
Orbital overlap is reduced by the strained geometry.
D.
The molecules are flat.
E.
More than one of the above.
(17)
Which of the following statements is(are) correct?
A.
Heterolytic cleavage leads to radical (unpaired-electron) reactions.
B.
Homolytic cleavage leads to polar (charged-species) reactions.
C.
Both
a
and
b
are correct.
D.
Neither
a
nor
b
are correct.
(Use the following information for questions 18-19.) Consider the polar reaction shown below.
(18)
The first step involves
A.
attack of the Cl on the double bond
B.
loss of a proton (H
+
)from the alkene
C.
attack on the proton of HCl by the sigma-bond electrons between the C’s
D.
attack on the proton of HCl by the pi-bond electrons between the C’s
E.
formation of a negatively charged carbon species, a
carbanion
(19)
In the second step of this reaction
A.
Cl is a nucleophile and the carbocation is an electrophile
B.
the HCl proton is a nucleophile
C.
the sigma-bond electrons act as a electrophile
D.
the pi-bond electrons act as an electrophile
E.
homolytic cleavage occurs
Use the following reaction for Questions 20 — 23.
(20)
Which of the products above is preferred?
A.
A
B.
B
C.
Neither is preferred. There is a 50:50 mix of the two.
D.
The reaction does not occur under these conditions.
(21)
Which of the following intermediates would lead to product
A
if the reaction leading to that product
did
occur?
A.
B.
C.
Neither intermediate is possible.
(22)
Which of the following statements is
TRUE
?
A.
A is the preferred product because the reaction leading to A is slower than that leading to B.
B.
B is the preferred product because the reaction leading to B is slower than that leading to A.
C.
A is the preferred product because the intermediate leading to A is lower in energy.
D.
B is the preferred product because the intermediate leading to B is lower in energy.
E.
The reaction does not occur.
(23)
The rule governing the product distribution is
A.
Zaitsev’s Rule
B.
Markovnikov’s Rule
C.
Carbocation rearrangement
D.
The "nonspecific" rule
E.
The Rule of Thumb
(24)
Which of the following is the correct designation for the molecule shown?
A.
cis
B.
trans
C.
E
D.
Z
E.
None of these.
(25)
Compared to single bonds, double bonds are:
A.
longer and weaker
B.
shorter and weaker
C.
trigonal and weaker
D.
shorter and stronger
E.
orthogonal
