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O-Chem Mega Problem Set

1.​ Which of the following cations is not a resonance structure of A?

a.​

b.​

c.​

d.​

Classify A, B, and C as resonance structures or isomers of each other.

a.​ A is an isomer of B and C

b.​ B is an isomer of A and C
c.​ C is a resonance structure of A and B
d.​ A is an isomer of B, and B is a resonance structure of C
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Assign formal charge to each labeled atom. All nonbonded electron pairs are drawn in.

What is the molecular formula for entacapone?

What is the hybridization of the N, C, and O atoms in the given molecule?

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Which of the following compounds does not have a net dipole?

a.​ BrCH2Br
b.​ CH3OCH3
c.​ (CH3)2CO
d.​ Cl3CCCl3

Which structure is another way of drawing compound A?

Give the formal charge on the highlighted carbon in each species. All H’s and electrons on the
highlighted carbon are drawn in.
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Draw a valid Lewis structure for each compound.

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With reference to anion A, label compounds B–E as an isomer or resonance structure of A. For
each isomer, indicate what bonds differ from A. (P. 1.51)

Add curved arrows to show how the first resonance structure can be converted to the second.
(P. 1.54)

Follow the curved arrows to draw a second resonance structure for each species. (P. 1.55)
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Draw a second resonance structure for each ion. Then draw the resonance hybrid. (P. 1.56)
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Draw all reasonable resonance structures for each species. (P. 1.57)

Which of the given resonance structures (A, B, or C) contributes most to the resonance hybrid?
Which contributes least? (P. 1.58)
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Consider the compounds and ions with curved arrows drawn below. Draw the resonance
structure when the curved arrows give a second valid resonance structure. When they generate
an invalid Lewis structure, explain why it is unacceptable. (P. 1.59)

Convert each molecule to a skeletal structure. (P. 1.64)

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Convert the following condensed formulas into skeletal structures. (P. 1.65)

Predict the hybridization and geometry around each highlighted atom. (P. 1.66)
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What orbitals are used to form each highlighted bond? For multiple bonds, indicate the orbitals
used in individual bonds. (P. 1.67)

Use the symbols δ+ and δ- to indicate the polarity of the highlighted bonds. (P. 1.72)
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Label the polar bonds in each molecule. Indicate the direction of the net dipole (if there is one).

CHAPTER 3 (Functional Groups)

Which of the following compounds and hydrogen bond both to another molecule like itself and to
water?

Rank A, B, and C in order of increasing boiling point.

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Which compound exhibits the weakest intermolecular forces?

In addition to an aromatic ring, what functional groups are present in metoprolol?

What functional group is not present in penicillin G?

a.​ Amide
b.​ Carboxylic acid
c.​ Amine
d.​ Sulfide
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Which compound is not water soluble?

Which statement describes the physical properties of A, B, and C?

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Which labeled site is unlikely to react with a nucleophile?

For each alkane: (a) classify each carbon atom as 1º, 2º, 3º, or 4º; (b) classify each hydrogen
atom as 1º,2º, or 3º. (P. 3.35)
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Identify the functional groups in each molecule. Classify each alcohol, alkyl halide, amide, and
amine as 1º,2º, or 3º. (P. 3.36)
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Salinosporamide A is an anticancer agent isolated from marine sediment. (P. 3.37)

What types of IMFs are exhibited by each complex? (3.39)

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Which of the following molecules can H-bond to another molecule like itself? Which one can
H-bond to water? (3.40)

Rank the compounds in each group in order of increasing boiling point. (3.44)
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Predict the water solubility of each of the following organic molecules. (3.47)

Using the principles of solubility, predict which sunscreen is more readily washed off when
swimming. Explain.
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Label the electrophilic and nucleophilic sites in each molecule.

By using only electron density arguments, determine whether the following reactions will occur.
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Give the IUPAC name for the given alkane.

Give the IUPAC name for the given cycloalkane.

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Which compound does not contain a trans disubstituted cyclohexane?

Classify each reaction as an oxidation, reduction, or neither.

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How are A and B related to each other?

a.​ Constitutional isomers

b.​ Stereoisomers
c.​ Identical
d.​ Not isomers of each other

How are C and D related to each other?

a.​ Constitutional isomers

b.​ Stereoisomers
c.​ Identical
d.​ Not isomers of each other

Which statement describes the substituents in the more stable chair conformation of E?

a.​ The butyl and OH groups are both equatorial

b.​ The butyl group is equatorial and the OH is axial
c.​ The OH group is equatorial and the butyl group is axial
d.​ The butyl and OH groups are both axial
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Which Newman projection depicts the lowest-energy conformation of (CH3)2CHCH(CH3)2?

Which compound has the highest BP?

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Convert each 3D model to a Newman projection around the indicated bond. (4.40)

Give the IUPAC name for each compound.

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Draw the structure corresponding to each IUPAC name.

a.​ 3-ethyl-2-methylhexane
b.​ Sec-butylcyclopentane
c.​ 4-isopropyl-2,4,5-trimethylundecane
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d.​ Cyclobutylcycloheptane
e.​ 3-ethyl- 1,1-dimethylcyclohexane
f.​ 4-butyl- 1, 1-diethylcyclooctane
g.​ 6-isopropyl-2, 3-dimethyldodecane
h.​ 2,2,6,6,7-pentamethyloctane
i.​ Cis-1-ethyl-3-methylcyclopentane
j.​ Trans-1-tert-butyl-4-ethylcyclohexane

Draw the structure of each alkane and cycloalkane from the given incorrect name. Then give the
IUPAC name for each compound.
a.​ 7-ethyl-3,6-dimethylnonane
b.​ 4-ethyl-3-isopropylheptane
c.​ 3-ethyl-1,4-dimethylcycloheptane
d.​ 1-ethyl-3-methyl-5-isopropylcyclohexane
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Give the IUPAC name for each compound.

Rank the following alkanes in order of increasing BP (4.46).

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