Assessment Schedule
Chemistry 2.5 90309
Describe the structural formulae and reactions of compounds containing selected organic
functional groups.
While the writers of this assessment have worked to compile a resource that meets NCEA requirements, it has
no official status and teachers may wish to adjust questions and the assessment schedule as they see fit.
Question
ONE
(i)
Evidence
Structural formula or IUPAC name:
(a) propan-2-ol
(b) 2-methylbut-2-ene
(c) but-1-yne
(d)
H
C
O
CH2 CH2 CH3
Achievement
Merit
4 correct answers
6 correct with
correct number
for side chains
and functional
groups
O
(e)
CH3 CH2 CH2 CH2 C
OH
O
(f)
Cl
CH3 C
CH2
CH3
Cl
Functional group names:
(a) alcohol
(b) alkene
(c) alkyne
(d) ester
3 correct answers
(ii)
secondary
Correct answer
circled
TWO
(a) (i)
Structural isomers have the same molecular
formula e.g. C4H8 , but must have different
structures i.e. different bonding order of their
atoms.
(a) (ii)
CH2
CH
CH2
CH3
but-1-ene
CH3 CH
CH
but-2-ene
CH3
C
CH2
CH3
2-methylpropene
CH3
Definition
correct
3 structures
correctly drawn
names not
required
Excellence
2
Question
TWO
(b)
Evidence
Achievement
Merit
H
Structures
correct but
names incorrect
OR one structure
and one name
correct
All correct
One factor
recognised
Compares the
two formulae
or structures
2 correct answers
4 correct
answers
CH3
C
C
Cl
Cl
cis 1,2-dichloroprop-1-ene
Excellence
H
Cl
C
C
Cl
CH3
trans 1,2-dichloroprop-1-ene
(c)
CH3CH=CCl2 and CH3CCl=CHCl are
structural isomers because they have the
same molecular formulae but different
structures.
CH3CH=CCl2 can not exhibit geometrical
isomerism because one carbon of the double
bond has two identical Cl atoms attached.
In (b) two forms exist because:
 different groups on each carbon of
the double bond
 no free rotation around double bond
THREE
a.
CH3 CH2 CH2 CH3
b.
CH3
CH3
c.
C
CH2
CH3 C O CH2 CH2 CH3
O
CH3
d.
CH3
C
CH2
OH OH
FOUR
(a) (i)
(a) (ii)
Bromine solution
The solution which is cyclohexene should
decolorize the bromine solution (orange
brown to colourless) immediately.
The solution which is cyclohexane will not
decolorize the bromine solution
immediately. (Loss of colour may occur on
standing in light for 20 mins or more)
(or equivalent reaction detail using KMnO4
instead of bromine solution).
correct
Observations
correct for one.
Correct
observations
for both
substances.
Recognises the
differences in
the structures
and relates to
forming cis
and trans in
part (b)
3
Question
Evidence
(b)
Cyclohexene undergoes an addition reaction
with bromine in which the C=C is broken
and the bromine atoms form C-Br bonds at
each of these carbon atoms. This reaction
occurs readily with shaking.
Achievement
Br
Merit
Excellence
One equation
correct OR
recognises
addition or
substitution
Two equations
correct OR
recognises
addition AND
substitution
Full discussion
including
equations
2 structures
correct + 1 name
or Reagent D
correct.
2 structures +
2 names +
Reagent D
correct
All correct.
+ Br
2
Br
Cyclohexane undergoes a substitution
reaction in which initially C-H bond(s) must
be broken first and then the bromine atom(s)
bonds to the carbon atom. This reaction is
slow to proceed, and usually requires light or
UV light to speed up reaction time.
Br
UV light
+ Br
2
mono-substitution only shown
CH3
FIVE
A:
CH3
CH
CH
CH3
Cl
2-chloro-3-methylbutane
B:
CH3
CH3 CH
CH2 CH2 Cl
1-chloro-3-methylbutane
C:
3-methylbutan-1-ol
Reagent D: Cr 2O72- / H+
or MnO4- / H+
E:
CH3
CH3 CH
CH2 C
O
O Na
4
Question
Evidence
SIX
(a)
CH3
H
Achievement
CH3
C
O
C
H
O
H
O
C
C
C
C
H
H
H
H
Merit
Excellence
Structure drawn
correctly.
O
H
Sufficiency Statement. These exams are not pre-tested. The statements below are a guide
and schools should feel free to adjust them to get a sensible distribution.
Achieved A total of SEVEN opportunities answered correctly at Achieved or higher.
Merit
A total of NINE opportunities answered correctly with 4 at Merit or higher.
Excellence A total of TEN opportunities answered correctly with 2 at Excellence, and 5 at Merit
or higher.