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OCR AS/A Level Chemistry A (H032/H432)
Module 4 Topic Test – Core Organic Chemistry
1
Which volume of oxygen gas, at room temperature and pressure, is required for complete
combustion of 1.25 × 10–3 mol of propan-1-ol?
A
105 cm3
B
120 cm3
C
135 cm3
D
150 cm3
Your answer
2
[1]
Three of the following displayed formulae represent the same isomer of C3H4Cl2 but one
structure represents a different isomer, X.
Which displayed formula represents X?
Your answer
© OCR 2016
[1]
Page 1
OCR AS/A Level Chemistry A (H032/H432)
Module 4 Topic Test – Core Organic Chemistry
3
Which alcohol will not react with potassium dichromate(VI) in sulfuric acid?
A
H3CH2CH(OH)CH2CH3
B
CH3CH2CH(CH3)CH2OH
C
(CH3)2CHCH(CH3)OH
D
(CH3CH2)2C(CH3)OH
Your answer
4
[1]
A section of a polymer chain is shown below.
Identify the monomer that would give rise to this section of addition polymer.
A
E-But-2-ene
B
Z-But-2-ene
C
Methylpropene
D
Propene
Your answer
© OCR 2016
[1]
Page 2
OCR AS/A Level Chemistry A (H032/H432)
Module 4 Topic Test – Core Organic Chemistry
5
Which statement about the two alkenes CH3CH2CH=CH2 and CH3CH=CHCH3 is
correct?
A
Neither exhibits cis–trans isomerism.
B
Neither may be polymerised.
C
Neither reacts with bromine to form 1,4-dibromobutane.
D
Neither reacts with hydrogen to form butane.
Your answer
6
[1]
Hydrobromic acid reacts with ethene to form bromoethane.
What is the best description of the organic intermediate?
A
It is a free radical.
B
It contains carbon, hydrogen and bromine.
C
Its structure is planar.
D
It is an electrophile.
Your answer
7
[1]
1,2-Dibromo-3-chloropropane (DBCP) has been used in the control of earthworms in
agricultural land.
What would be the best synthesis of DBCP?
A
CH3CH2CH2Cl + 2Br2  DBCP + 2HBr
B
CH3CHBrCH2Br + Cl2  DBCP + HCl
C
CH2=CHCHBr2 + HCl  DBCP
D
CH2=CHCH2Cl + Br2  DBCP
Your answer
© OCR 2016
[1]
Page 3
OCR AS/A Level Chemistry A (H032/H432)
Module 4 Topic Test – Core Organic Chemistry
8
The organic compounds labelled A to E below are all produced by living organisms.
(a)
State the systematic name of compound A.
………………………………………………………………………………… [1]
(b)
Compound D reacts readily with hydrogen chloride in an addition reaction. Two
products are formed in this reaction, but one of the products is formed in much
greater amounts than the other.
(i)
Draw the structure of both possible addition products of this reaction.
product 1
© OCR 2016
product 2
[2]
Page 4
OCR AS/A Level Chemistry A (H032/H432)
Module 4 Topic Test – Core Organic Chemistry
(ii)
State and explain which of the two possible products will be formed in
greater amounts.
Include a diagram of the intermediate in the mechanism of this reaction in
your answer.
……………………………………………………………………………………….
……………………………………………………………………………………….
……………………………………………………………………………………….
…………………………..……………………………………………………
9
[2]
A student carries out the following experiment to investigate the reaction between
hexane and chlorine. The chlorine is made by reaction of aqueous sodium chlorate(I)
with dilute hydrochloric acid.
Procedure
Observations
1 cm3 of hexane is mixed with 1 cm3 dilute
aqueous sodium chlorate(I) in a test-tube.
The mixture forms two colourless layers.
1 cm3 dilute hydrochloric acid is slowly added to The acid mixes with the lower layer,
the mixture.
which turns a pale green colour.
The tube is then stoppered and shaken.
The pale green colour moves to the upper
layer, leaving the lower layer colourless.
The tube is placed under a bright light and
shaken at regular intervals for about 10
minutes. The stopper is loosened regularly to
release any pressure.
The pale green colour slowly
disappears leaving two colourless
layers after about 10 minutes.
The reaction of hexane with chlorine took place when the bright light was switched on.
© OCR 2016
Page 5
OCR AS/A Level Chemistry A (H032/H432)
Module 4 Topic Test – Core Organic Chemistry
(a)
Give the skeletal formula of one possible organic product of this reaction.
[1]
(b)
Explain why this type of mechanism is likely to produce a mixture of organic
products.
…………………………………………………………………………………………….
……………………………………………………………………………………
10
[1]
Alcohols are used in organic synthesis.
Pentan-2-ol can be prepared by the alkaline hydrolysis of 2-iodopentane.
CH3CH(I)CH2CH2CH3 + NaOH → CH3CH(OH)CH2CH2CH3 + NaI
The reaction mixture is boiled for 20 minutes.
(a)
State the most appropriate technique that could be used to boil the reaction
mixture for 20 minutes.
………………………………………………………………………………………. [1]
(b)
Describe the mechanism for the alkaline hydrolysis of 2-iodopentane.
In your answer, include the name of the mechanism, curly arrows and relevant
dipoles.
name of mechanism: …………………………………………………………
[4]
© OCR 2016
Page 6
OCR AS/A Level Chemistry A (H032/H432)
Module 4 Topic Test – Core Organic Chemistry
11
(a)
Alcohols can be converted into haloalkanes in a substitution reaction.
Plan an experiment to prepare approximately 0.1 mol of 2-bromopentane,
CH3CHBrCH2CH2CH3, from pentan-2-ol, CH3CH(OH)CH2CH2CH3.
Your plan should include a calculation of the mass of alcohol required and
details of the chemicals to be used in the reaction.
……………………………………………………………………………………………
…………………………………………………………………………………………….
…………………………………………………………………………………..
(b)
[2]
Alcohols can be converted into alkenes in an elimination reaction.
The elimination of H2O from pentan-2-ol forms a mixture of organic products.
Give the names and structures of all the organic products in the mixture.
Your answer should explain how the reaction leads to the different isomers.
……………………………………………………………………………………………
……………………………………………………………………………………………
……………………………………………………………………………………………
……………………………………………………………………………………………
……………………………………………………………………………………………
……………………………………………………………………………………………
……………………………………………………………………………………………
……………………………………………………………………………………………
……………………………………………………………………………………………
……………………………………………………………………………………
© OCR 2016
[6]
Page 7
OCR AS/A Level Chemistry A (H032/H432)
Module 4 Topic Test – Core Organic Chemistry
12
This question is about cyclic organic compounds.
The table shows some information about cycloalkanes
(a)
These cycloalkanes are members of the same homologous series and have the
same general formula
(i)
What is meant by the term homologous series?
………………………………………………………………………………………
………………………………………………………………………………………
………………………………………………………………………………………
………………………………………………………………………………… [2]
(ii)
State the general formula for these cycloalkanes.
.................................................................................................................. [1]
(b)
The C–C–C bond angles in cyclohexane are 109.5°.
State and explain the shape around each carbon atom in cyclohexane.
shape.................................................................
explanation..............................................................................................................
………………………………………………………………………………………… [2]
© OCR 2016
Page 8
OCR AS/A Level Chemistry A (H032/H432)
Module 4 Topic Test – Core Organic Chemistry
(c)
In the absence of ultraviolet radiation, cyclopropane undergoes an addition
reaction with bromine.
Suggest the structure of the organic product formed in this reaction.
[1]
(d)
Cyclohexane can be prepared from hexane.
Construct the equation for this reaction
…………………………………………………………………………………………. [1]
© OCR 2016
Page 9
OCR AS/A Level Chemistry A (H032/H432)
Module 4 Topic Test – Core Organic Chemistry
13
Compound G is a branched-chain organic compound that does not have E and Z
isomers.
Elemental analysis of compound G gave the following percentage composition by
mass: C, 55.8%; H, 7.0%; O, 37.2%.
The mass spectrum and infrared spectrum of compound G are shown below.
Mass Spectrum
Infrared Spectrum
© OCR 2016
Page 10
OCR AS/A Level Chemistry A (H032/H432)
Module 4 Topic Test – Core Organic Chemistry
•
Calculate the empirical and molecular formulae for compound G.
•
Write the formulae for the particles responsible for peak X and peak Y in the mass
spectrum.
•
Draw the structure of compound G.
Explain fully how you arrive at a structure for compound G using all the evidence
provided.
…………………………………………………………………………………………………….
…………………………………………………………………………………………………….
…………………………………………………………………………………………………….
……….……………………………………………………………………………………………
……….……………………………………………………………………………………………
……………….……………………………………………………………………………………
……….……………………………………………………………………………………………
……….……………………………………………………………………………………………
……….……………………………………………………………………………………………
……….……………………………………………………………………………………………
……………….……………………………………………………………………………………
……………………….……………………………………………………………………………
……………………………….……………………………………………………………………
……………………………………….……………………………………………………………
……………………………………………….……………………………………………………
……………………………………………………….……………………………………………
……………………………………………………………….……………………………………
……………………………………………………………………….……………………………
……………………………………………………………………………….……………………
……………………………………………………………………………………….……………
© OCR 2016
Page 11
OCR AS/A Level Chemistry A (H032/H432)
Module 4 Topic Test – Core Organic Chemistry
……………………………………………………………………………………………….……
…………………………………………………………………………………………………….
…………………………………………………………………………………………………….
…………………………………………………………………………………………………….
…………………………………………………………………………………………………….
…………………………………………………………………………………………………….
….…………………………………………………………………………………….………. [7]
© OCR 2016
Page 12
OCR AS/A Level Chemistry A (H032/H432)
Module 4 Topic Test – Core Organic Chemistry
14
The flowchart shows how 2-methylbut-2-ene can be converted into a number of
organic products.
(a)
Complete the flowchart by drawing an organic structure in the box below.
[1]
(b)
Identify reagent A.
........................................................................................................................... [1]
(c)
In the flowchart, reaction R forms a mixture of two alcohols that are structural
isomers of C5H12O.
(i)
State the reagents and conditions needed for reaction R.
.................................................................................................................. [1]
(ii)
Suggest why 2-methylbut-2-ene is less soluble in water than either of the
structural isomers formed.
.......................................................................................................................
.......................................................................................................................
.................................................................................................................. [2]
© OCR 2016
Page 13
OCR AS/A Level Chemistry A (H032/H432)
Module 4 Topic Test – Core Organic Chemistry
(d)
Describe the oxidation reactions of propan-1-ol when using a suitable oxidising
agent.
Indicate how the use of different reaction conditions can control which organic
product forms.
Include reagents, observations and equations in your answer.
In your equations, use structural formulae and use [O] to represent the oxidising
agent.
.................................................................................................................................
.................................................................................................................................
.................................................................................................................................
.................................................................................................................................
.................................................................................................................................
.................................................................................................................................
.................................................................................................................................
.................................................................................................................................
.................................................................................................................................
.................................................................................................................................
.................................................................................................................................
.................................................................................................................................
.................................................................................................................................
.................................................................................................................................
.................................................................................................................................
........................................................................................................................... [6]
[Total Marks: 52]
© OCR 2016
Page 14
OCR AS/A Level Chemistry A (H032/H432)
Module 4 Topic Test – Core Organic Chemistry
MARK SCHEME
Question
1
Answer
C
Mks
1
Question Source and Guidance Notes
2
D
1
Q15 - GCE - Chemistry A - Specimen - H032/01
3
D
1
Q16 - GCE - Chemistry A - Specimen - H032/01
4
D
1
Q17 - GCE - Chemistry A - Specimen - H032/01
5
C
1
6
D
1
7
D
1
8(a)
4-methylheptan-3-ol 
1
Modified from UCLES, A Level Chemistry, June 1990, Question Paper
9250/1, Question 22
Modified from UCLES, A Level Chemistry, June 1988, Question Paper
9250/3, Question 23
Modified from UCLES, A Level Chemistry, June 1989, Question Paper
9250/3, Question 25
Q22(a) - GCE - Chemistry A - Specimen - H032/01
Q14 - GCE - Chemistry A - Specimen - H032/01
ALLOW 4-methyl-3-heptanol
8(b)(i)
2
Q22(b)(i)- GCE - Chemistry A - Specimen - H032/01
ALLOW any unambiguous structure or formula
ALLOW ECF on the second structure for hydrogen
atom errors if candidate tries to convert to a
displayed/structural formula, but the carbon skeleton
must be correct
8(b)(ii)
9(a)
correct structure of either possible carbocation
intermediate shown 

the tertiary halogenoalkane (which will be labelled
as either product 1 or product 2) is identified as the
one formed in greater amounts …
because the carbocation more stable on C3 than
C2 owtte ✓
any mono or multiple substituted chlorohexane –
e.g.
© OCR 2016
2
Q22(b)(ii) - GCE - Chemistry A - Specimen - H032/01
Topics
Alcohols, haloalkanes and
analysis/ Amount of substance
Basic concepts and
hydrocarbons/ Alkenes
Alcohols, haloalkanes and
analysis
Basic concepts and
hydrocarbons/ Alkenes
Alkenes
Demand
H
M
M
M
Alkenes
Organic synthesis
Basic concepts and
hydrocarbons
Basic concepts and
hydrocarbons/
Alkenes/Amount of substance
Alkenes
M
MH
If both carbocations are drawn, only one needs to be
correct to score the mark
ALLOW ECF from (i) for correct justification of
product formed in greater amount based on incorrect
structures
1
Q23(b)(i) - GCE - Chemistry A - Specimen - H032/01
Basic concepts and
hydrocarbons/Alkanes
M
Page 15
OCR AS/A Level Chemistry A (H032/H432)
Module 4 Topic Test – Core Organic Chemistry
Question
9(b)
10(a)
10(b)
Answer
(because) substitution can replace any H atom
/multiple substitution owtte 
Reflux 
Nucleophilic substitution 
Mechanism
−
Curly arrow from lone pair on OH to δ+ carbon
Mks
1
Question Source and Guidance Notes
Q23(b)(ii) - GCE - Chemistry A - Specimen - H032/01
IGNORE vague statements about free radical
reactions being random
ALLOW termination can join alkyl radicals to form
larger hydrocarbons owtte
1
4
Q5(a)(i) - GCE - Chemistry A - Specimen - H032/02
Q5(a)(ii) - GCE - Chemistry A - Specimen - H032/02
The curly arrow must start from the oxygen atom of the
OH− and must start from either the lone pair or the
negative charge
atom 
Topics
Basic concepts and
hydrocarbons/Alkanes
Alcohols, haloalkanes and
analysis/Organic
synthesis/Planning
Alcohols, haloalkanes and
analysis/Organic
synthesis/Planning
Demand
M
LMH
LMH
Curly arrow and dipole on C–I bond 
Correct products 
DO NOT ALLOW attack by NaOH
11(a)
(Minimum) n(pentan-2-ol) required = 0.1× 88 = 8.8g

React the alcohol with a mixture of NaBr AND
H2SO4
AND warm (to distil off the product) 
© OCR 2016
2
Q5(b) - GCE - Chemistry A - Specimen - H032/02
ALLOW HBr
Alcohols, haloalkanes and
analysis/Amount of substance
H
Page 16
OCR AS/A Level Chemistry A (H032/H432)
Module 4 Topic Test – Core Organic Chemistry
Question
11(b)
Answer
Level 3 (5–6 marks)
Applies knowledge of elimination reactions to
provide the correct names and structures of all
three alkenes AND
Full, detailed explanation of formation of both types
of isomers linked to the reaction, with clear
understanding of both types of isomerism
The explanations show a well-developed line of
reasoning which is clear and logically structured. The
information presented is relevant to the compounds
drawn/named.
Level 2 (3–4 marks)
Applies knowledge of elimination reactions to
provide the correct name and structure for
pent-1-ene
AND
Correct structures of stereoisomers of pent-2-ene
but full names missing or incorrect
AND
Explanation of formation of at least one type of
isomers in some detail.
Mks
6
Question Source and Guidance Notes
Q(5)(c) - GCE - Chemistry A - Specimen - H032/02
Indicative scientific points may include:
Topics
Basic concepts and
hydrocarbons/Alkenes
Demand
LMH
• - the elimination can produce a double bond in either
•
•
•
the 1- or the 2- position (through combination of the
hydroxyl group with a hydrogen from either the 1st or
the 3rd carbon)
- this leads to the formation of structural isomers (pent1-ene and pent-2-ene)
- pent-2-ene exhibits stereoisomerism / E/Z isomerism /
cis–trans isomerism because it has two different groups
attached to each carbon atom
- there are two possible isomers of pent-2-ene and
three in total
The explanations show a line of reasoning presented
with some structure. The information presented is in the
most-part relevant to the compounds drawn/named.
Level 1 (1–2 marks)
Applies knowledge of elimination reactions to
name and draw the structures of organic products.
Either name OR structure should be correct for two
compounds.
AND
Attempts to explain formation of one type of
isomer. The information about isomerism is basic and
communicated in an unstructured way. The relationship
to the compounds drawn/named may not be clear.
0 marks
No response or no response worthy of credit.
© OCR 2016
Page 17
OCR AS/A Level Chemistry A (H032/H432)
Module 4 Topic Test – Core Organic Chemistry
Question
12(a)(i)
12(a)(ii)
12(b)
Answer
(series of compounds with the)
same functional group
OR same/similar chemical properties
OR same/similar chemical reactions
✓
each successive/subsequent member differing by
CH2 ✓
CnH2n ✓
Tetrahedral ✓
Mks
2
1
2
Demand
Basic concepts and
hydrocarbons/Alkanes
LM
Q1(a) - GCE - Chemistry A - June 2014 - F322/01
Q1(b) - GCE - Chemistry A - June 2014 - F322/01
Mark each point independently
IGNORE surrounded by four atoms
IGNORE four areas of electron charge repel
IGNORE four electron pairs repel (one could be lp)
DO NOT ALLOW atoms repel
1
Topics
Q1(a)(i) - GCE - Chemistry A - June 2014 - F322/01
IGNORE references to physical properties
IGNORE has same general formula (in question)
DO NOT ALLOW have the same empirical formula OR
have the same molecular formula
four bonding pairs repel OR four bonds repel✓
12(c)
Question Source and Guidance Notes
Q1(c) - GCE - Chemistry A - June 2014 - F322/01
ALLOW correct structural OR displayed OR skeletal
formula
OR mixture of the above (as long as unambiguous)
Basic concepts and
hydrocarbons /Alkanes
L
Basic concepts and
hydrocarbons/Alkenes
H
Basic concepts and
hydrocarbons/Alkanes
L
ALLOW structure of 1,2-isomer
IGNORE molecular formula
DO NOT ALLOW, structure of 1,1-isomer OR 2,2isomer
12(d)
C6H14  C6H12 + H2 
1
Q1(d)(i) - GCE - Chemistry A - June 2014 - F322/01
ALLOW correct structural OR displayed OR skeletal
formula OR mixture of the above (as long as
unambiguous)
ALLOW any correct multiple
IGNORE state symbols
© OCR 2016
Page 18
OCR AS/A Level Chemistry A (H032/H432)
Module 4 Topic Test – Core Organic Chemistry
Question
13
Answer
Mks
7
Question Source and Guidance Notes
Q8(b) - GCE - Chemistry A - June 2014 - F322/01
ANNOTATE ANSWER WITH TICKS AND CROSSES
Topics
Alcohols, haloalkanes /
Analytical techniques
Demand
MH
ALLOW mass of C = 0.558 x 86 or 48 AND mass of H
=
0.07 x 86 or 6 AND mass of O = 0.372 x 86 = 32
+ charge required for each response
ALLOW one mark if both formulae are correct but with
no charge/incorrect charge
ALLOW any possible fragments that contain C, H
and/or O that have the correct mass. E.g. Peak X
indicates C2OH+,
Peak Y indicates C2H5O+
Unfeasible fragments are not allowed e.g. C3H9 +
(too many H atoms)
LOOK ON THE SPECTRUM for labelled absorbance
which can be given credit
Candidates must link absorbance to bond in order to
gain the mark
ALLOW 1700 cm-1
For 2500–3300 cm-1, ALLOW 2900 cm-1or any stated
wavenumber with range 2500–3300cm-1
ALLOW wavenumber range up to 2400–3500cm-1
ALLOW structural, skeletal or displayed formula.
DO NOT ALLOW ECF from incorrect molecular formula
14(a)
1
Q7(a) - GCE - Chemistry A - June 2014 - F322/01
ALLOW correct structural OR displayed OR skeletal
formula OR mixture of the above
DO NOT ALLOW molecular formula
ALLOW dichloro or diiodo compound instead
© OCR 2016
Alcohols, Halogenoalkanes
and Analysis
M
Page 19
OCR AS/A Level Chemistry A (H032/H432)
Module 4 Topic Test – Core Organic Chemistry
Question
14(b)
14(c)(i)
14(c)(ii)
Answer
Reagent A: correct halogen e.g. Br2 / bromine
Steam AND acid catalyst ✓
Mks
1
14(d)
Q7(b) - GCE - Chemistry A - June 2014 - F322/01
ALLOW Cl2 if dichloro compound drawn
ALLOW I2 if diiodo compound drawn
IGNORE state symbols
Answer must match box from (a) to score
1
Does not contain OH group(s)
OR does not contain hydroxyl group(s)
OR is not an alcohol 
Does not form hydrogen bonds with water 
Question Source and Guidance Notes
2
Q7(c)(i) - GCE - Chemistry A - June 2014 - F322/01
+
ALLOW H / named acid / H2SO4 / H3PO4
ALLOW H2O(g)
ALLOW water only if a temperature of 100 °C or above
is quoted.
IGNORE any temperature given with steam
IGNORE pressure
Q7(c) - GCE - Chemistry A - June 2014 - F322/01
ALLOW ORA throughout
DO NOT ALLOW OH– (ions) / hydroxide (ions)
Topics
Basic Concepts and
Hydrocarbons
Demand
L,M
Basic Concepts and
Hydrocarbons
L,M,H
Basic Concepts and
Hydrocarbons
‘Does not form hydrogen bonds’ is not sufficient’
6
Q7(d) - GCE - Chemistry A - June 2014 - F322/01
ANNOTATE ANSWER WITH TICKS AND CROSSES
ETC
ALLOW H2SO4 and K2Cr2O7
Alcohols, Halogenoalkanes
and Analysis
L,M,H
ALLOW correct displayed formula OR correct
structural formula OR skeletal formula OR a mixture of
the above
DO NOT ALLOW molecular formulae
ALLOW C3H7OH for propan-1-ol in equations

DO NOT ALLOW CH3CH2COH for aldehyde
IGNORE further oxidation of aldehyde
ALLOW CH3CH2CO2H for carboxylic acid
TOTAL
© OCR 2016
52
Page 20
OCR AS/A Level Chemistry A (H032/H432)
Module 4 Topic Test – Core Organic Chemistry
OCR Resources: the small print
OCR’s resources are provided to support the teaching of OCR specifications, but in no way constitute an endorsed teaching method that is required by the Board, and the
decision to use them lies with the individual teacher. Whilst every effort is made to ensure the accuracy of the content, OCR cannot be held responsible for any errors or
omissions within these resources. We update our resources on a regular basis, so please check the OCR website to ensure you have the most up to date version.
© OCR 2016
© OCR 2016
Page 21