CHEMISTRY 2.5
An assessment for AS90309
Describe the structural formulae and reactions of compounds containing selected
organic functional groups.
Credits: Four
INSTRUCTIONS
Answer ALL questions.
© New Zealand Institute of Chemistry 2007
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You should spend about 45 minutes on this assessment
QUESTION ONE:
In the structure of the p-Coumaric acid molecule shown below, three different structural groups have
been circled.
O
A
H H
C C C
B
HO
OH
C
On the table below name each functional group
Group circled
A
B
C
Name of functional group
3
QUESTION TWO:
Complete the table below by writing the correct systematic (IUPAC) name for each compound.
Compound
Structural formula
Name of compound
O
A
CH3 CH2 C
OH
B
O
CH3 CH2 CH2 C
OCH3
C
CH3 CH2 CH
CH3
OH
D
CH3
CH3 CH CH CH CH2 CH2
QUESTION THREE:
The condensed structural formula of the compound 1,2-dibromopropene is CH3CBr=CHBr .
(a)
Give the structural formula of the cis and trans isomers of this compound in the boxes below.
cis1,2-dibromopropene
trans1,2-dibromopropene
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(b)
The two other isomers of dibromopropene are 1,1-dibromopropene and 1,3 dibromopropene
(i) Draw the structural formula for the isomer which cannot exist as cis-trans isomers.
(ii)
Discuss the requirements for cis-trans isomerism using the isomers of dibromopropene
from (b) (i) above to illustrate your answer.
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QUESTION FOUR:
(a)
Draw structural formulae for the named compounds in the table below.
Name of compound
A
pent-2-ene
B
4-chloropentan-1-ol
C
3-methylbutanoic acid
D
2-methylpropan-2-ol
(b)
Classify compound D, from the table above, as a primary, secondary or tertiary alcohol by
circling your choice below:
Primary
(c)
Structural formula
Secondary
Tertiary
Describe a chemical test that would distinguish between compounds B and C. Include in your
answer:

the name of the reagent to be used

a description of the tests and the expected observations for each compound.
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QUESTION FIVE:
Propene, CH3CH=CH2, undergoes a number of reactions.
(a)
Reaction with hydrogen:
Write the equation of the reaction of propene with hydrogen
(b)
Reaction with HCl
In the boxes below draw the structural formula of the major and minor products of the reaction
of propene with HCl.
Major product
(c)
Minor product
Reaction with MnO4–
In the box below draw the structural formula of the product of the reaction of propene with
MnO4- and name it.
Name____________________________________
(d)
Polymerisation:
In the box below draw a section of the polymer formed from propene. Show at least two
repeating units.
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QUESTION SIX:
(a)
For the following reactions, write the structural formula of the organic product.
O
(i) CH3 C
NaOH
OH
(ii) CH3 CH2 OH
Conc. H2SO4
Heat
O
(iii) CH3 CH2 OH + CH3 C
Conc. H2SO4
OH
(b)
Heat
Identify the type of reaction occurring in each of the three reactions in (a). Select the type of
reaction from the list below.
addition
elimination
oxidation-reduction
acid-base ester formation
substitution
(i)__________________________
(ii)_________________________
(iii)________________________
(c)
Both ethane and ethene will react with aqueous bromine (Br2). Discuss why reaction with Br2
can be used to distinguish between these two compounds.
In your answer include:

the reaction conditions needed

the observations made

the type of reaction that occurs

equations for any reactions which occur

the names of any product(s) formed
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QUESTION 7:
Fats and oils are tri-ester molecules. Hydrolysis of a fat can be represented by the equation below:
CH2 O C
C17H35
CH
O
O C
C17H35
CH2
O
O C
+ 3 NaOH
3Na O C
C17H35
O
C17H35
O
(a)
Circle an ester linkage.
(b)
In the box below draw structural formula of compound X.
+
Compound X
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QUESTION EIGHT:
Complete the flow chart below by
 drawing structural formulae for the compounds A, B, C, D and E
 giving the IUPAC names for the compounds A, B, C, and D
 identifying reagent F.
A
CH3CH2CH2CH2OH
Name__________________
Reagent G
B
C4H8
Name__________________
H2SO4/H2O
H2SO4/H2O
C
D
Name__________________
Name__________________
Reagent H
E
C and E
react
Name__________________
Reagent J
F
C4H8O2