Download Practice Exam 2

NOTE: PLEASE NOTE THAT THIS PRACTICE TEST IS ONLY MEANT TO GIVE YOU
AN IDEA OF THE TYPES OF QUESTIONS THAT I WILL ASK. REMEMBER, THE
NUMBER AND NATURE OF THE TOPICS I COVER IN A PARTICULAR YEAR VARIES
BASED ON TIME AND NUMEROUS OTHER FACTORS. AS AN EXAMPLE, I SEE THAT
THERE IS VERY LITTLE FROM CH 7, OSMOSIS, ETC!
1.
a) (8 pts.) Provide the functional group names for the groups indicated. Functional
group names are listed on the right and may be used (i) once, (ii) more than once, or (iii)
not at all. Make sure you consider the entire group.
Thyroxine
A.
B.
C.
D.
E.
F.
G.
H.
I.
J.
L.
alcohol
aldehyde
alkene
alkyne
aromatic
amide
amine
ester
ether
carboxylic acid
ketone
b) (2 pts.) In the structure of Thyroxine above, put a star on the chiral carbon atom(s).
2.
(3 pts.) Which of the following pairs of compounds are cis-trans isomers?
a)
and
b)
and
c)
d)
HC ≡ C-CH3
and
CH3-C ≡ CH
and
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e)
3.
and
(3 pts.) Which of the following is NOT typical of most organic compounds?
a) high melting point
b) poor solubility in water
c) low boiling point
d) covalent bonding
e) high flammability
4.
(8 pts.) For each of the following solutions, indicate if the [OH-] concentration is greater
than, less than, or equal to the [H3O+] concentration.
a) acidic solution
c) pH = 9
d) [OH-] = 1.0 x 10-6 M
d) [H3O] = 1.0 x 10-8 M
5.
greater than
greater than
greater than
greater than
less than
less than
less than
less than
(4 pts.) Pictured in the enclosed box below is one enantiomer of valine, an amino acid
used by nature in synthesizing proteins. Which of the molecules on the right is the same
enantiomer?
CO2H
H
NH2
CH3
6.
equal to
equal to
equal to
equal to
CO2H
H2N
H
CH3
CH3
H
CH3
NH2
CO2H
H2N
H
CO2H
O
||
(3 pts.) The common name of the compound CH3-C-OH is:
a) butanoic acid.
b) propanoic acid.
c) propionic acid.
d) acetic acid.
e) butyric acid.
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7.
(25 pts. total – 5 pts. each) For each reaction shown, (i) predict the major organic
product(s) produced AND (ii) write the IUPAC name for the product molecule(s) that
you determine.
OH
|
CH3-CH2-CH2-CH2-CH2
CH3
|
CH2=C-CH2-CH-CH3
|
Cl
[O]
Pt
+
H2
CH3
O
|
||
CH3-CH-CH2-C-O-CH2CH3
Η+
+
OH
|
CH3-CH-CH-CH3
|
CH3
H2O
H+, ∆
O
[O]
+
+
2Ag
2Ag(s) +
H
Cl
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8.
(3 pts.) Alkenes and alkynes are called unsaturated compounds because
a) they have the maximum number of hydrogen atoms attached to each carbon in the
compound.
b) they have fewer hydrogen atoms attached to the carbon chain than alkanes.
c) they have more hydrogen atoms attached to the carbon chain than alkanes.
d) they have more carbon atoms than alkanes.
e) they have fewer carbon atoms than alkanes.
9.
(3 pts.) A 10.0 mL of 0.121 M HCl is neutralized by 17.1 mL of KOH solution. The
molarity of the KOH solution is
a) 0.207 M
b) 0.4141 M
c) 0.0708 M
d) 0.428 M
e) 0.142 M
10.
(4 pts.) Rank the following compounds (that have similar mass) in order of decreasing
solubility in water: 3-pentanol (C5H11O), hexane (C6H14), 1-pentanal (C5H10O), and
butanoic acid (C4H8O2).
Most soluble
11.
→
Least soluble
(3 pts.) Tertiary alcohols cannot be oxidized because
a) there are no oxygen atoms to remove from the alcohol carbon.
b) there are no hydrogen atoms attached to the alcohol carbon.
c) the alcohol carbon is bonded to four groups so no oxygen can be added to it.
d) the alcohol carbon is bonded to four groups so no hydrogen can be added to it.
e) the alcohol carbon is too electronegative to have hydrogen removed from it.
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12.
(5 pts.) No matter how long you heat up the molecule shown below in the presence of an
acid, it does not dehydrate. Based on your knowledge of dehydration reactions, briefly
explain why a reaction does not occur for this molecule.
OH
13.
(3 pts.) What is(are) the product(s) of the complete combustion of any hydrocarbon?
a) CO only
b) CO2 only
c) CO + H2O
d) CO2 + H2O
e) H2O only
14.
(4 pts.) Draw the condensed structural formula of 4,5-dimethyl-1-hexyne.
15.
(4 pts.) Consider the following acid/base reaction:
HCl (g)
+
H2O (l)
Cl- (aq)
+
H3O+ (aq)
a) Is HCl a strong acid or a weak acid?
b) What is the conjugate base of the acid HCl?
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16.
(5 pts.) Glycerol (1,2,3-propanetriol) has a boiling point of 290 °C, while that of 1pentanol boils at 138 °C. Discuss the factors that contribute to the observed boiling
points of each of these molecules, and then explain why glycerol has a higher boiling
point than that of 1-pentanol.
17.
(3 pts.) Which of the following pairs of compounds are constitutional (structural) isomers?
a)
CH2 - CH2
|
|
CH2 - CH2
and
CH3 - CH - CH3
|
CH3
b) CH3 - CH2 - CH2 - CH3
and
CH3 - CH2 - CH3
c) CH3 CH3
|
|
CH2 – CH–CH3
and
d)
CH3 CH3
|
|
CH3 -C – C - CH3
|
|
CH3 CH3
18.
and
CH2-CH3
|
CH3 - CH2 - CH - CH3
CH3 CH3
|
|
CH3 - CH – CH- CH2-CH2-CH3
(3 pts.) Which of the following statements concerning aromatic compounds is NOT true?
a) A benzene ring can be represented by a hexagon with a circle inside of it.
b) Aromatic rings are very stable.
c) Benzene has conjugated pi bonds that are spread over the entire ring of C atoms.
d) Aromatic rings undergo the same reactions as alkenes.
19.
(4 pts.) A compound with the formula C4H8O has the following properties: (i) it can be made
from 2-methyl-1-propanol and (ii) it oxidizes easily to give a carboxylic acid. What is the
condensed structure of this compound?
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