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CHEMISTRY 150
March 20th, 2013
NAME:_______________________________
B. MacLean
__________________________________________________________________________________________
INSTRUCTIONS:
For questions that involve drawing organic structures, you may use either line-angle structures or condensed
structural formulas. Do not present carbon-skeleton structures for your answers.
__________________________________________________________________________________________
Question
Mark Obtained
Out of
A1-10
________
30
B1
________
18
B2
________
22
B3
________
12
B4
________
12
----TOTAL:
94
Section A: Multiple choice [2] per correct answer; total = 30 points
A1) What factor determines the order of water-solubility for a series of substances?
a) intermolecular forces
b) intramolecular forces
c) boiling points
d) molecular shape
A2) Which of the following molecules will not undergo oxidation?
a) 2-propanol
b) 2-methylpropanal
c) 2-methyl-2-butanol
(3o alcohol)
d) sec-butanol
A3) Which of the following reactions would be a condensation reaction?
a) saponification
b) esterification
c. acid + alcohol  ester + water
c) elimination
d) hydrolysis
A4) Which of the following compounds would be expected to have the highest degree of solubility in water?
a) 1-butanol
b) 1-propanol
c) 1,3-propane diol
2 OH groups
d) propanal
A5) Which of the following compounds can undergo a hydration reaction?
a) 2-propanol
b) butanoic acid
c) methyl ethanoate
d) 2-butene
hydration: addition reaction, involves a reactant with a multiple bond
A6) Which of the following is a real/correct IUPAC name?
a) 2-methylethanoic acid
aka propanoic acid
b) 3-butanone
aka 2-butanone (or just butanone)
c) 2,2-dimethylethanol
(aka 2-methyl-1-propanol)
d) 2-methylpropanal
A7) In benzene, there are ____ -bonds.
a) 2
b) 3
c) 6
d) none
A8) The two compounds, 3-methyl-2-pentanol and 2-ethyl-1-butanol are
a) skeletal isomers
b) functional group isomers
c) positional isomers
(see right)
d) not isomers
A9) Because of their pleasant aromas, ___________ are often included as components of perfumes.
a) alcohols
b) esters
c) ethers
d) carboxylic acids
A10) Which of the following molecules is a lactone? b
a
b
c
d
11) Zaitsev’s rule enables one to predict the major product of a(n) __________ reaction.
a) condensation
b) saponification
c) oxidation
d) elimination
12) Which of the following will not have a positional isomer?
a) 2-butanone
C=O bond can be in only one location of 4-C chain and still be a ketone
b) 2-pentanone
c) 1-propanol
d) 2-methyl-2-propanol
13) Carboxylic acids and ____________ which have the same number of carbons will be functional group
isomers.
a) ketones
b) alcohols
c) ethers
d) esters
14) When Benedict’s reagent is added to a test tube containing an unknown chemical, the test tube takes on a
silvery mirror-like appearance. The unknown chemical in the test tube must have been
a) a primary alcohol
b) a secondary alcohol
c) an aldehyde
d) a ketone
15) Which of the following molecules will cause the pH of a solution to rise when added?
a) ethanol
b) ethanoic acid
c) sodium ethanoate
d) ethanal
the only basic substance listed (c. base of carboxylic acid)
Section B: Long-answer problems. Answer the following questions in the space provided.
B1.
Provide names for each of the following structures in the spaces provided:
[18 points]
4-bromo-2-pentanone
1,1,1-trichloro-2-propanol
IUPAC: 2-methoxypropane
common: methyl-2-propyl ether
2-propyl butanoate
(also isopropyl, sec-propyl)
benzoic acid
3-methylbutanal
B2.
Complete the following chemical reactions using appropriate chemical structures. Where more than
one product structure is possible, show all structures and indicate which should be the major product: [22
points]
a
H+(cat)
H2O
[O]
b
major
H2SO4/180oC
c
H+(cat)
d
e
f
[O]
H2O
NaOH
[R]
g
Na+
-
B3.
Complete the following diagram by drawing chemical structures for each of the isomers requested in
the fields indicated [12 points]
this is the only option here
positional isomer
any aldehyde of the formula C 6H12O
functional group isomer
skeletal isomer
ketone with a different C skeleton
B4.
Arrange the following chemical compounds in order of increasing boiling points (i.e. lowest-tohighest). Important: pay attention to the ordering. [12]
methyl propanoate, pentanoic acid, 1-pentanol, hexane, butanoic acid, dimethyl ether
dimethyl ether < hexane < methyl propanoate < 1-pentanol < butanoic acid < pentanoic acid
LOWEST b.p.
HIGHEST b.p.
Ethers and alkanes of similar molar mass have similar boiling points; hexane heavier than dimethyl ether
Esters have dipole-dipole, but no H-bonding
Alcohols are H-bonders
Carboxylic acids are stronger H-bonders than alcohols