Download Questions

1.
Adrenalin is a hormone which raises blood pressure, increases the depth of breathing and delays
fatigue in muscles, thus allowing people to show great strength under stress.
Benzedrine is a pharmaceutical which stimulates the central nervous system in a similar manner
to adrenalin.
HO
CH 2
CH(CH 3 )
NH 2
HO
Benzedrine
(a)
(i)
H
CH(OH)
CH 2
N
CH 3
Adrenalin
On the structure for benzedrine mark with a (*) any asymmetric carbon atom that
causes chirality.
(1)
(ii)
Suggest why adrenalin is more soluble in water than is benzedrine.
..........................................................................................................................
..........................................................................................................................
..........................................................................................................................
(2)
(b)
Give the structural formulae of the organic products obtained when benzedrine reacts
with:
(i)
an aqueous acid such as dilute hydrochloric acid;
(1)
(ii)
ethanoyl chloride in the absence of a catalyst;
(1)
(iii)
excess ethanoyl chloride in the presence of the catalyst anhydrous aluminium
chloride.
(2)
St John's RC Comprehensive School
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(d)
It is possible to eliminate a molecule of water from adrenalin which for the purpose of
this question may be represented as R–CH(OH)–CH2–NH–CH3. Draw the structural
formulae of the two stereoisomers produced.
(2)
(e)
The mass spectra of both benzedrine and adrenalin have a peak at a mass/charge ratio of
44. Draw the structure of the species which give these peaks.
(i)
in benzedrine;
(1)
(ii)
in adrenalin.
(1)
(Total 11 marks)
2.
(a)
An alcohol with the molecular formula C4H9OH is chiral.
(i)
Explain what is meant by the term chiral.
............................................................................................................................
............................................................................................................................
(2)
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(ii)
Draw two diagrams to clearly represent the optical isomers that result from the
chirality of this alcohol.
(2)
(iii)
Explain how you could distinguish between these two isomers experimentally.
............................................................................................................................
............................................................................................................................
............................................................................................................................
(2)
(b)
Alcohols react with carboxylic acids to form esters.
(i)
Write an equation for a typical esterification reaction.
............................................................................................................................
(1)
(ii)
Suggest how this type of reaction could be used to form polyesters.
Experimental details are not required.
............................................................................................................................
............................................................................................................................
............................................................................................................................
(3)
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(iii)
Suggest, with reasoning, whether a laboratory coat made from a polyester might be
damaged by a spillage on it of hot concentrated aqueous sodium hydroxide
solution.
............................................................................................................................
............................................................................................................................
............................................................................................................................
(2)
(iv)
Give another type of reagent that could be used to make an ester from an alcohol.
............................................................................................................................
(1)
(Total 13 marks)
3.
(a)
Write equations to show the reactions of the amino acid alanine, CH3CH(NH2)COOH,
with:
(i)
HCl
………….……………….……………………………………………………..
(1)
(ii)
NaOH
………….……………….……………………………………………………..
(1)
(b)
Explain why alanine has a relatively high melting temperature (290 °C).
………….……………………...……………………………………………………..
………….……………………...……………………………………………………..
………….……………………...……………………………………………………..
(2)
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(c)
Alanine exists as two optical isomers.
(i)
Draw diagrams to show the structures of the two optical isomers.
(2)
(ii)
Explain how separate pure samples of each optical isomer can be distinguished
from each other.
………….……………….……………………………………………………..
………….……………….……………………………………………………..
………….……………….……………………………………………………..
(2)
(d)
A mixture of isomeric alkenes is obtained when butan-2-ol is dehydrated.
(i)
Draw diagrams to show the two structural isomers obtained when butan-2-ol
is dehydrated.
(2)
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(ii)
One of the above structural isomers can itself exist as two different stereoisomers.
Draw diagrams to clearly illustrate these two stereoisomers, and name this type of
stereoisomerism.
Type of stereoisomerism ……………………………………………………..
Diagrams
(3)
(Total 13 marks)
4.
The pain-relieving drug ibuprofen has the formula
CH 3
H
C
CH 3
CH 2
C
CH 3
(a)
H
CO 2 H
A molecule of this compound is chiral. Explain, with the aid of diagrams, how two
optical isomers result from chiral a centre. Identify the chiral centre in such a molecule
and explain how these isomers could be distinguished from each other.
(4)
(b)
Compounds A and B, shown below, are used as intermediates in the manufacture of
ibuprofen.
CH 3
H
C
CH 3
CH 2
C
CH 3
CH 3
O
H
C
CH 3
CH 2
C
CH 3
A
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H
OH
B
6
(i)
Suggest how infra-red spectroscopy could be used to identify an impurity in a
sample of ibuprofen which is known to be one of these two compounds.
A table of infra-red absorbencies is given below.
Bond
C-H
Assignment
Wavenumbers/cm–1
alkanes
alkenes, arenes
2850 - 2950
3000 - 3100
arenes
1450 - 1650
C=O
aldehydes, ketones, esters,
carboxylic acids
1680 - 1750
O-H
free
hydrogen bonded in alcohols or phenols
hydrogen bonded in carboxylic acids
3580 - 3670
3230 - 3550
2500 - 3300
benzene ring
(3)
(ii)
Suggest a simple chemical test which would distinguish between A and B.
(2)
(iii)
Treatment of either A or B if heated with a mixture of aqueous sodium hydroxide
and potassium manganate(VII) solution would produce the same compound.
Suggest the structure of this compound.
(2)
(c)
A tablet of ibuprofen contains a very small quantity of the drug and the remainder of the
tablet material is unreactive.
In an analysis 50 tablets were reacted with 100.0 cm3 of 1.00 mol dm–3 aqueous sodium
hydroxide, an excess. The ibuprofen reacted as a weak acid. When the reaction was
complete, the remaining aqueous sodium hydroxide was titrated with 2.00 mol dm–3
hydrochloric acid. 25.75 cm3 of the acid were required for neutralisation.
(i)
Calculate the mass, in mg, of ibuprofen in each tablet.
(Mr for ibuprofen = 206)
(5)
(ii)
Calculate the number of molecules of ibuprofen that this tablet represents.
(Avogadro constant h = 6.023 × 1023 mol–1)
(2)
(d)
Ibuprofen is almost insoluble in aqueous solutions at pH 3 but if the pH is raised to 8 then
the ibuprofen becomes reasonably soluble. Account for these observations.
(4)
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(e)
Under the appropriate conditions ibuprofen reacts with ethanol to produce a substance
with a characteristic odour. Identify the functional group in ibuprofen that would react
with the ethanol. Suggest the conditions needed for the reaction to take place and identify
the product.
(3)
(Total 25 marks)
5.
(a)
Alkenes such as ethene will take part in homolytic, free radical addition reactions to form
polymers such as poly(ethene).
(i)
Define the terms homolytic and free radical.
(2)
(ii)
Draw a repeating unit of the polymer that would be made by the same mechanism
from phenylethene, C6H5CH=CH2.
(2)
(iii)
Outline the difficulties involved in the disposal of polymers such as
poly(phenylethene) by combustion and by landfill.
(2)
(iv)
State a property of poly(phenylethene) and suggest why this makes it
particularly useful.
(2)
(b)
Ethene, C2H4, reacts with concentrated sulphuric acid by electrophilic addition of H+ and
HSO4– across the double bond to give CH3CH2OSO3H.
(i)
Suggest a mechanism for this electrophilic addition reaction.
(3)
(ii)
Describe a simple chemical test to confirm that the carbon-carbon double bond is
not present in the product.
(2)
(c)
(i)
Use the concepts of the different types of covalent bonds and bond enthalpy to
explain the structure of the benzene ring.
(5)
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(ii)
Explain why benzene normally reacts by electrophilic substitution rather than by
electrophilic addition.
(2)
(Total 20 marks)
6.
This question is about propanal, CH3CH2CHO, propanone, CH3COCH3, and propanoic acid,
CH3CH2CO2H.
(a)
Explain why all three compounds are soluble in water.
....................................................................................................................................
....................................................................................................................................
(1)
(b)
Propanal and propanone contain the carbonyl group.
State a chemical test for the presence of this group. Give the result of a positive test.
Test ...........................................................................................................................
Result ........................................................................................................................
(2)
(c)
Propanal can be distinguished from propanone by its oxidation to propanoic acid.
(i)
Name an oxidising agent you would use.
.........................................................................................................................
.........................................................................................................................
(1)
(ii)
State the colour change you would observe during the oxidation.
From ...................................................... to ......................................................
(1)
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(iii)
State how propanone can be distinguished from propanal using infra-red spectra.
You are not expected to give actual absorption values, but you should indicate the
bonds in the molecules which would give rise to the distinguishing absorptions.
.........................................................................................................................
.........................................................................................................................
(1)
(d)
A useful test for carboxylic acids is that they will neutralise sodium carbonate solution.
Write a balanced equation, including state symbols, for the neutralisation of sodium
carbonate solution by propanoic acid.
(2)
(e)
Give the names of TWO other inorganic chemicals that could be used to make sodium
propanoate from propanoic acid.
....................................................................................................................................
....................................................................................................................................
(2)
(Total 10 marks)
7.
Alanine, 2-aminopropanoic acid, is the simplest chiral amino acid found in nature and is
optically active.
H
H2N
C
CH3
St John's RC Comprehensive School
O
C
O
H
10
(a)
(i)
Explain the meaning of the term chiral.
.....................................................................................................................................
.....................................................................................................................................
(1)
(ii)
How is optical activity detected experimentally?
.....................................................................................................................................
.....................................................................................................................................
(2)
(iii)
If alanine is made from propanoic acid the product mixture does not show optical
activity. Explain why this is so.
.....................................................................................................................................
.....................................................................................................................................
.....................................................................................................................................
(2)
(b)
Alanine reacts with both acids and bases. Give the structural formulae of the compounds
you would expect if alanine reacts with
hydrochloric acid
sodium hydroxide
(2)
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(c)
Alanine has a high melting temperature of 300 °C, much higher than would be expected
for the structure given at the start of the question.
Draw the structure that is actually present in the solid, and explain why the melting
temperature is so high.
............................................................................................................................................
...........................................................................................................................................
............................................................................................................................................
(2)
(d)
Polyamides are made from a diacid dichloride and a diamine; they are condensation
polymers.
(i)
Explain the term condensation polymer.
.....................................................................................................................................
.....................................................................................................................................
(1)
(ii)
Suggest the structural formula of a diacid dichloride and a diamine that could be
reacted to form a polyamide.
(2)
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(iii)
Draw sufficient of the polymer chain that would result from the reaction of the
compounds in (ii) to make the structure of the polymer clear.
(2)
(iv)
Alanine could be converted to CH3CH(NH2)COCl which on its own could
polymerise to a polyamide. Draw the structure of the polymer chain showing three
alanine repeating units and all the bonds in the amide links.
(2)
(Total 16 marks)
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8.
X and Y are isomers with the molecular formula C7H6O2.
(a)
Complete the table with the observations you would make when separate samples of X
and Y are warmed gently in test-tubes with the following solutions.
Solution
Observation with X
Observation with Y
sodium carbonate
Brady’s reagent
(2,4-dinitrophenylhydrazine)
potassium dichromate(VI) +
sulphuric acid
(6)
(b)
Both X and Y can take part in reactions in which esters are formed.
(i)
Complete the structural formula of the ester which forms when X reacts with
methanol.
St John's RC Comprehensive School
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(1)
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(ii)
Y reacts with ethanoyl chloride to form an ester.
Draw the displayed formula of ethanoyl chloride.
(1)
(iii)
Complete the displayed formula of the ester which forms when Y reacts with
ethanoyl chloride.
(2)
(iv)
When X forms an ester with methanol, a catalyst is needed for the reaction to
proceed at a reasonable speed when heated gently.
Name a suitable catalyst for the esterification reaction.
...........................................................................................................................
(1)
(v)
Explain why ethanoyl chloride is reactive enough to form an ester with Y at a
reasonable speed without a catalyst and without heating.
...........................................................................................................................
...........................................................................................................................
...........................................................................................................................
...........................................................................................................................
(2)
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(c)
The benzene ring in Y reacts readily with bromine in a substitution reaction.
(i)
Name the type of reagent which attacks a benzene ring in substitution reactions.
...........................................................................................................................
(1)
(ii)
Give the formula of the species which attacks the benzene ring when it reacts with
bromine in a substitution reaction.
.............................................................................................................................
(1)
(iii)
Suggest a structural formula for an organic product of the reaction of bromine with
Y.
(1)
(iv)
Y reacts with bromine more readily than benzene does. Suggest a reason for this.
...........................................................................................................................
...........................................................................................................................
...........................................................................................................................
...........................................................................................................................
(1)
(Total 17 marks)
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9.
Study the reaction scheme below, then answer the questions that follow.
(a)
(i)
Butanal contains a carbonyl group. State a chemical test for a carbonyl group and
describe the result of the test.
Test .........................................................................................................................
Result .....................................................................................................................
(2)
(ii)
An isomer of butanal also possesses a carbonyl group, but cannot be oxidised by
acidified sodium dichromate(VI). Give the structural formula of this isomer and
its name.
Structural formula ..................................................................................................
Name ......................................................................................................................
(2)
(iii)
Another isomer of butanal contains a carbonyl group and can be oxidised by
acidified sodium dichromate(VI). Draw the displayed formula of this isomer.
(1)
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(b)
Compound X is a colourless liquid that smells of pineapples.
(i)
To what class of compounds does X belong?
...............................................................................................................................
(1)
(ii)
Ethanol, C2H5OH, reacts with butanoic acid to form compound X. Complete the
diagram below to show the structural formula of X and the other product.
(1)
(iii)
Give the name of compound X.
...............................................................................................................................
(1)
(iv)
What type of attacking species is ethanol in this reaction?
...............................................................................................................................
(1)
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(c)
Describe what you would expect to see during Reaction 2.
......................................................................................................................................
......................................................................................................................................
......................................................................................................................................
(1)
(d)
Explain why Reaction 4 is far more vigorous than Reaction 3.
......................................................................................................................................
......................................................................................................................................
......................................................................................................................................
......................................................................................................................................
(2)
(Total 12 marks)
10.
(a)
Propanoic acid, CH3CH2COOH, can be prepared from carbon dioxide and an organic
reagent.
Name this organic reagent and state the conditions for the preparation.
Reagent ........................................................................................................................
Conditions ....................................................................................................................
......................................................................................................................................
(3)
(b)
Describe what you would see and write the equations for the reactions of propanoic acid
with:
(i)
a solution of sodium carbonate
Observation ........................................................................................................
Equation .............................................................................................................
(2)
St John's RC Comprehensive School
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(ii)
solid phosphorus pentachloride.
Observation ........................................................................................................
Equation .............................................................................................................
(2)
(c)
Propanoic acid can also be prepared from propanal, CH3CH2CHO. State the reagents for
this conversion.
Reagents ......................................................................................................................
(2)
(d)
1-aminobutan-2-ol, CH3CH2CH(OH)CH2NH2, is an active ingredient in some deodorant
sprays.
It can be prepared from propanal by the following two-step process.
Step
Step
1
CH3CH2CH(O
CH3CH
2
C
H
O
(i)
H
)
C
N
2
CH3CH2CH(OH)C
H
2
N
H
2
For Step 1
State the reagents and conditions.
............................................................................................................................
............................................................................................................................
Name the type of reaction.
............................................................................................................................
(3)
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(ii)
For Step 2
State the reagents and conditions.
............................................................................................................................
............................................................................................................................
Name the type of reaction.
............................................................................................................................
(3)
(e)
Write the structural formula of the organic product formed when 1-aminobutan-2-ol
reacts with:
(i)
ethanoyl chloride, CH3COCl
(2)
(ii)
hydrochloric acid.
(1)
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(f)
1-aminobutan-2-ol exists as two isomers with the same structural formula.
Identify the type of isomerism and draw the TWO isomers, showing clearly the
difference between them.
Type of isomerism .......................................................................................................
(3)
(Total 21 marks)
11.
This question is about compounds with the molecular formula C4H8O.
(a)
(i)
Draw the displayed formulae of TWO isomers, A and B, which are both aldehydes.
Give their systematic names.
A
B
Name ....................................................... .......................................................
(4)
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(ii)
Suggest an instrumental method by which these isomers, A and B, could be
distinguished.
Outline how the results would differ.
...........................................................................................................................
...........................................................................................................................
...........................................................................................................................
(2)
(b)
Substance C, butanone, is another isomer of C4H8O.
(i)
Name a reagent which results in the same observation when it reacts with all three
isomers, A, B and C.
Reagent .............................................................................................................
...........................................................................................................................
Observation ......................................................................................................
...........................................................................................................................
...........................................................................................................................
(2)
(ii)
Name a reagent where the resulting observation for C would be different from that
for A and B.
Reagent .............................................................................................................
...........................................................................................................................
Observation with C ...........................................................................................
...........................................................................................................................
...........................................................................................................................
Observation with A and B ................................................................................
...........................................................................................................................
...........................................................................................................................
(3)
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(c)
(i)
Suggest structural formulae for TWO more isomers of C4H8O, D and E, which are
cyclic and react with sodium to give off hydrogen.
D
E
(2)
(ii)
Both A and B can be oxidised to carboxylic acids. These acids will then react with
either of the isomers D or E in the presence of a strong acid as a catalyst.
What is the name given to the products of this type of reaction?
...........................................................................................................................
(1)
(iii)
For one of the carboxylic acids formed from A or B and one of the isomers D or E,
draw a displayed formula of the product formed when they react together.
(2)
(Total 16 marks)
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12.
This question is about butanal, CH3CH2CH2CHO, and several related compounds.
(a)
What would you see when Brady’s reagent is added to a sample of butanal?
.....................................................................................................................................
(1)
(b)
F, G and H are three isomers of butanal which are each tested with sodium, Benedict’s
reagent and Brady’s reagent. The results are shown in the table below.
Key:
= positive result
= negative result
Sodium
Benedict’s reagent
Brady’s reagent
F
G
H
Suggest structural formulae for F, G and H.
F
G
H
(3)
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(c)
An ester with the formula, CH3CH2CH2CO2CH2CH3, is heated under reflux with aqueous
sodium hydroxide.
(i)
Give ONE advantage of “heating under reflux”, rather than simply boiling the two
liquids together in a beaker.
...........................................................................................................................
...........................................................................................................................
...........................................................................................................................
(1)
(ii)
Name the ester.
...........................................................................................................................
(1)
(iii)
Name the TWO products of this reaction.
...........................................................................................................................
(2)
(iv)
What type of reaction is taking place?
...........................................................................................................................
(1)
(Total 9 marks)
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13.
Methanoic acid and ethanol react together to form ethyl methanoate, HCOOC2H5, and water.
This reaction is reversible and can be allowed to reach equilibrium.
HCOOH(l) + C2H5OH(l)
(a)
HCOOC2H5 (l) + H2O(l)
ΔH = +45 kJ mol–1
Draw the full structural formula of ethyl methanoate, showing all bonds.
(1)
(b)
What type of organic compound is ethyl methanoate?
.....................................................................................................................................
(1)
(c)
In an experiment, 3.00 mol methanoic acid, HCOOH, and 6.25 mol ethanol, C2H5OH,
were mixed together. A small quantity of catalyst was added. The mixture was left for
several days in a water bath to reach equilibrium at constant temperature.
(i)
Complete the table.
Number of moles in the reaction mixture
HCOOH
C2H5OH
HCOOC2H5
H2O
at start of
experiment
3.00
6.25
0.00
0.00
at equilibrium
0.50
(2)
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(ii)
Write an expression for the equilibrium constant, Kc, for the reaction.
(1)
(iii)
Calculate Kc for the reaction at the temperature of the experiment. The total volume
of the equilibrium mixture was 485 cm3.
(2)
(iv)
State and explain whether Kc for this reaction has units.
...........................................................................................................................
...........................................................................................................................
(1)
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(d)
(i)
The temperature of this equilibrium mixture is lowered.
Explain the effect of this on the value of the equilibrium constant and hence on the
yield of ethyl methanoate.
...........................................................................................................................
...........................................................................................................................
...........................................................................................................................
...........................................................................................................................
...........................................................................................................................
...........................................................................................................................
...........................................................................................................................
(4)
(ii)
A student added more catalyst to the mixture.
State, giving a reason, what would happen to the composition of the equilibrium
mixture.
...........................................................................................................................
...........................................................................................................................
(1)
(Total 13 marks)
14.
A chemist has synthesised a compound W believed to be
Cl
HO
CH
CH
CH
O
C
OH
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(a)
State and explain what you would see if W is reacted with:
(i)
sodium carbonate solution
...........................................................................................................................
...........................................................................................................................
...........................................................................................................................
(2)
(ii)
bromine water.
...........................................................................................................................
...........................................................................................................................
...........................................................................................................................
...........................................................................................................................
(3)
(b)
W shows both types of stereoisomerism.
(i)
How many stereoisomers of W are there? Briefly explain your answer.
...........................................................................................................................
...........................................................................................................................
...........................................................................................................................
...........................................................................................................................
(2)
(ii)
Explain why W shows optical isomerism.
...........................................................................................................................
...........................................................................................................................
...........................................................................................................................
(2)
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(c)
Describe how you would show that W contains chlorine.
.....................................................................................................................................
.....................................................................................................................................
.....................................................................................................................................
.....................................................................................................................................
.....................................................................................................................................
.....................................................................................................................................
.....................................................................................................................................
.....................................................................................................................................
(5)
(Total 14 marks)
15.
This question concerns the reactions of some compounds of nitrogen.
(a)
The ammonium ion reacts with water and behaves as an acid.
NH4+(aq) + H2O(l)
(i)
NH3(aq) + H3O+(aq)
Identify the TWO conjugate acid-base pairs in the spaces provided.
acid 1 ................................... base 1 ...................................
acid 2 ................................... base 2 ...................................
(1)
(ii)
Write the expression for the acid dissociation constant, Ka, of the ammonium ion.
(1)
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(iii)
A solution of ammonium chloride has a pH of 5.00 at 25°C.
Ka for the ammonium ion is 5.62 × 10–10 mol dm–3 at 25°C.
Calculate the concentration of this solution. State any assumptions you have made.
(4)
(iv)
Use the following table and your answer from part (iii) to suggest a suitable
indicator for the titration of ammonia solution with hydrochloric acid. Justify your
answer.
Indicator
pKIn
thymol blue
1.7
methyl red
5.1
phenolphthalein
9.3
...........................................................................................................................
...........................................................................................................................
(2)
(b)
Hydrogen cyanide is a weak acid in aqueous solution.
Write an equation to show why aqueous solutions of cyanide ions are alkaline.
.....................................................................................................................................
(1)
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(c)
Hydrogen cyanide reacts with propanal as follows:
CH3CH2CHO + HCN → CH3CH2CH(OH)CN
Propanal is reacted with a solution of potassium cyanide, KCN, containing a little dilute
sulphuric acid.
(i)
What type of reaction is this?
...........................................................................................................................
(1)
(ii)
Give the mechanism for the reaction.
(3)
(iii)
It is important that the pH is neither too acidic nor too alkaline if a good yield of
the product is to be obtained. Explain why this is so.
...........................................................................................................................
...........................................................................................................................
...........................................................................................................................
...........................................................................................................................
(2)
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(d)
In an investigation of the kinetics of the nucleophilic substitution reaction between
1-chloropropane and potassium cyanide in aqueous ethanolic solution, the reaction was
found to be first order with respect to 1-chloropropane and first order with respect to
cyanide ions.
(i)
Give the rate equation for the reaction.
...........................................................................................................................
(1)
(ii)
Write a mechanism for the reaction that is consistent with this rate equation.
(3)
(Total 19 marks)
16.
(a)
The table below shows the acid dissociation constants, Ka, of three carboxylic acids.
Structural formula
Ka/ mol dm–3
Chloroethanoic
CH2ClCO2H
1.3 × 10–3
Dichloroethanoic
CHCl2CO2H
5.0 × 10–2
Trichloroethanoic
CCl3CO2H
2.3 × 10–1
Acid
St John's RC Comprehensive School
35
(i)
Write an expression for the acid dissociation constant, Ka, of chloroethanoic acid.
(1)
(ii)
Calculate the pH of a 0.0010 mol dm–3 solution of chloroethanoic acid, making the
usual assumptions.
(3)
(iii)
Which acid would have the lowest pH at a concentration of 0.0010 mol dm–3?
Use both the data and the structure of the acids to justify your answer. No further
calculation is required.
...........................................................................................................................
...........................................................................................................................
...........................................................................................................................
...........................................................................................................................
(2)
St John's RC Comprehensive School
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(b)
Chloroethanoic acid, CH2ClCO2H, reacts with methanol, CH3OH, in the presence of a
sulphuric acid catalyst.
(i)
Draw the displayed formula and give the name of the organic product formed.
Displayed Formula
Name .................................................................................................................
(3)
(ii)
What name is given to the functional group formed in this organic product?
...........................................................................................................................
(1)
(iii)
What type of reagent is methanol in this reaction? Explain why it is able to behave
in this way and describe how it attacks the chloroethanoic acid.
You may find it helpful to draw a diagram.
...........................................................................................................................
...........................................................................................................................
...........................................................................................................................
(3)
St John's RC Comprehensive School
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(iv)
How would you convert the organic product of the reaction between
chloroethanoic acid and methanol back into the original compounds?
...........................................................................................................................
...........................................................................................................................
...........................................................................................................................
(2)
(Total 15 marks)
17.
Consider the following compounds.
H H H
Compound X
O
H—C—C—C—C
H
H H H
O—C—H
H
H
H
C
C
H
H
Compound Y
H
C—–C—–H
OH H
H
Compound Z
H
H
H—–C—–C—–C—–C
OH H
St John's RC Comprehensive School
H
H
O
38
(a)
Name the functional groups present in the three compounds X, Y and Z.
Compound
Functional groups present
X
Y
Z
(3)
(b)
Compounds X, Y and Z are heated separately with alkaline ammoniacal silver nitrate
solution.
Draw the full structural formula, showing all bonds, of any organic product formed.
If a reaction does not occur, write ‘no reaction’.
Product from X
Product from Y
Product from Z
(3)
St John's RC Comprehensive School
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(c)
Draw the formulae of the organic products formed by the reaction of
(i)
X, CH3CH2CH2COOCH3, with aqueous sodium hydroxide solution.
(2)
(ii)
Z, CH2(OH)CH2CH2CHO, with hydrogen cyanide.
(1)
(Total 9 marks)
18.
Name the following organic compound
HCHO
...............................................................................................................................................
(Total 1 mark)
St John's RC Comprehensive School
40
à19. (a)
Draw the displayed formula of a branched chain ketone containing five carbon atoms.
(2)
(b)
Give the systematic name for this ketone.
.....................................................................................................................................
(1)
(c)
What is the molecular formula of the alcohol this ketone could be made from?
.....................................................................................................................................
(1)
(d)
An alcohol can be converted into a ketone by oxidation with sodium dichromate(VI) and
sulphuric acid.
Explain why refluxing the mixture first, rather than immediately distilling the product
over from the beginning, results in a higher yield of the ketone.
.....................................................................................................................................
.....................................................................................................................................
.....................................................................................................................................
.....................................................................................................................................
(1)
(Total 5 marks)
St John's RC Comprehensive School
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20.
Compound V, the structure of which is shown below, is found in human sweat.
CH3
C
H
C
O
C
CH3 CH2 CH2
OH
Compound V
(a)
Compound V contains two functional groups.
Identify both functional groups and state a chemical test for each. The result of each test
should also be included in your answer.
One functional group in V ...........................................................................................
Test and result .............................................................................................................
.....................................................................................................................................
.....................................................................................................................................
The other functional group in V .................................................................................
Test and result .............................................................................................................
.....................................................................................................................................
.....................................................................................................................................
(4)
(b)
Compound V can be converted into two carbonyl compounds W and X, shown below.
H
C
CH3CH2CH2
C
O
C
O
OH
W
(i)
CH3
O
X
Which of the compounds W or X would react when warmed with Fehling’s
solution to give a red precipitate? Justify your answer.
...........................................................................................................................
...........................................................................................................................
(1)
St John's RC Comprehensive School
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(ii)
Compound W can be reduced in two steps to compound Y of molecular formula
C2H6O2.
Identify Y.
...........................................................................................................................
(1)
(iii)
Compound W can be oxidised to compound Z of molecular formula C2H2O4.
Identify Z.
...........................................................................................................................
(1)
(c)
The compounds Y and Z react together under suitable conditions to form a polymer.
(i)
Draw the structural formula of the repeating unit for the polymer formed.
(2)
(ii)
What type of polymerisation reaction occurs between compounds Y and Z?
...........................................................................................................................
(1)
(Total 10 marks)
St John's RC Comprehensive School
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21.
Ethanal, CH3CHO, can be converted into 2-hydroxypropanoic acid, CH3CH(OH)COOH.
State the reagents and conditions needed for each step in this synthesis.
...............................................................................................................................................
...............................................................................................................................................
...............................................................................................................................................
...............................................................................................................................................
...............................................................................................................................................
(Total 4 marks)
22.
(a)
Name the homologous series to which the compound CH3CH2CHO belongs.
.....................................................................................................................................
(1)
(b)
Describe what you would see if a sample of CH3CH2CHO was warmed with Benedict’s
solution.
.....................................................................................................................................
.....................................................................................................................................
.....................................................................................................................................
.....................................................................................................................................
.....................................................................................................................................
(2)
(Total 3 marks)
St John's RC Comprehensive School
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23.
One of the alarm pheromones for ants, compound Q, has the molecular formula C6H10O.
(a)
State what can be deduced about compound Q from each of the following pieces of
information.
(i)
Q, C6H10O, is a non-cyclic organic compound. When saturated it would contain 14
hydrogen atoms.
...........................................................................................................................
...........................................................................................................................
(1)
(ii)
Compound Q does not react with sodium.
...........................................................................................................................
...........................................................................................................................
(1)
(iii)
One mole of compound Q reacts with one mole of bromine molecules, Br2, in the
absence of sunlight.
...........................................................................................................................
...........................................................................................................................
(1)
(iv)
Compound Q gives a yellow precipitate with Brady’s reagent,
2,4-dinitrophenylhydrazine.
...........................................................................................................................
(1)
(v)
When compound Q is warmed with Benedict’s solution, a red precipitate is
formed.
...........................................................................................................................
(1)
St John's RC Comprehensive School
45
(vi)
Compound Q exists in the trans form.
...........................................................................................................................
...........................................................................................................................
...........................................................................................................................
(1)
(vii) Given that compound Q is a straight chain molecule with the two functional groups
next to one another, give the displayed formula of Q.
(2)
(b)
(i)
Compound Q, C6H10O, can be converted into C6H14O in two steps.
Give the reagent and any catalyst needed for each step.
Step 1 ................................................................................................................
...........................................................................................................................
Step 2 ................................................................................................................
...........................................................................................................................
(2)
(ii)
Name the functional group which would now be present?
...........................................................................................................................
(1)
(Total 11 marks)
St John's RC Comprehensive School
46
24.
The drug ibuprofen can be synthesised from benzene by the route shown below.
CH3
CH3
CH3
CH3
H—C—CH3
H—C—CH3
H—C—CH3
H—C—CH3
CH2
CH2
CH2
CH2
Step A
Step B
CO /Pd
catalyst
Step C
C
O
CH3
H—C—OH
CH3
H—C—CO2H
CH3
Ibuprofen
(a)
Name the type and mechanism of the reaction in Step A, and suggest a suitable reagent
and catalyst.
Type and mechanism ..................................................................................................
Name of the reagent for Step A ..................................................................................
Catalyst .......................................................................................................................
(3)
(b)
Step C is a reduction.
Give ONE reason why lithium tetrahydridoaluminate, LiAlH4, is preferred to hydrogen as
a reducing agent in this reaction.
.....................................................................................................................................
.....................................................................................................................................
.....................................................................................................................................
(2)
St John's RC Comprehensive School
47
(c)
A sample of the final product was analysed by combustion. 1.00 g was burnt in oxygen. It
produced 2.78 g carbon dioxide and 0.786 g water.
State the molecular formula of ibuprofen and show that these results are consistent with
it.
(4)
St John's RC Comprehensive School
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(d)
Ibuprofen can be analysed by instrumental methods. The infrared spectra of ibuprofen
and two other drugs, aspirin and paracetamol, not necessarily in that order, are shown
opposite.
CH3
H—C—CH3
CH2
Ibuprofen has the formula
H—C—CO2H
CH3
CO2H
O
—O—C
Aspirin has the formula
CH3
OH
Paracetamol has the formula
CH3
H—N—C
O
(i)
Explain, referring to the structure of each molecule, why infrared spectroscopy is
not a good technique to distinguish aspirin from ibuprofen.
...........................................................................................................................
...........................................................................................................................
...........................................................................................................................
(1)
St John's RC Comprehensive School
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(ii)
Deduce which of X, Y or Z is the infrared spectrum of paracetamol, giving a piece
of evidence from the spectrum you select.
Spectrum X
Transmittance (%)
100
50
0
4000
Spectrum Y
3000
2000
Wavenumber / cm–1
1500
1000
3000
2000
Wavenumber / cm–1
1500
1000
3000
2000
Wavenumber / cm–1
1500
1000
Transmittance (%)
100
50
0
4000
Spectrum Z
Transmittance (%)
100
50
0
4000
St John's RC Comprehensive School
50
...........................................................................................................................
...........................................................................................................................
...........................................................................................................................
...........................................................................................................................
(1)
(iii)
Ibuprofen and aspirin can be distinguished using their mass spectra.
A line at mass/charge ratio 57 occurs only in the mass spectrum of ibuprofen.
Give the formula of the ion which produces this line.
...........................................................................................................................
Suggest the mass/charge ratio of one line which occurs in the mass spectrum of
aspirin but not ibuprofen, and the formula of the species which produces it.
...........................................................................................................................
...........................................................................................................................
(3)
(Total 14 marks)
25.
Which one of the following organic compounds does not exist?
A
an ester which is a structural isomer of a carboxylic acid C3H6O2
B
a carboxylic acid which is a structural isomer of an ester C2H4O2
C
an aldehyde which is a structural isomer of a ketone C3H6O
D
a ketone which is a structural isomer of an aldehyde C2H4O
(Total 1 mark)
26.
This question concerns a proposed two-stage synthetic route to prepare butanamide,
CH3CH2CH2CONH2
Carboxylic acid
St John's RC Comprehensive School

NH3
Acyl chloride 
butanamide
51
(a)
A suitable starting material for this preparation would have the formula
A
CH3CH2CH2COH
B
CH3CH2CH2CH2COOH
C
CH3CH2CH2COOH
D
CH3CH2CH2CH2OOH
(1)
(b)
Each stage in the sequence produced a 50% yield of required product. What is the
minimum number of moles of the carboxylic acid which should be used in order to
produce one mole of butanamide?
A
0.25
B
2.00
C
2.50
D
4.00
(1)
(c)
Which of the following reagents is needed to convert the carboxylic acid into the acyl
chloride?
A
chlorine
B
phosphorus(V) chloride
C
hydrogen chloride
D
ethanoyl chloride
(1)
(Total 3 marks)
St John's RC Comprehensive School
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27.
This question concerns the following compounds containing four carbon atoms.
A
Butanoic acid, CH3CH2CH2COOH
B
Butanone, CH3COCH2CH3
C
Propyl methanoate, HCOOCH2CH2CH3
D
Butanoyl chloride, CH3CH2CH2COCl
Select, from A to D, the compound that
(a)
can be made by the oxidation of a primary alcohol.
A
B
C
D
(1)
(b)
would be expected to react most rapidly with ethanol.
A
B
C
D
(1)
St John's RC Comprehensive School
53
(c)
would have 4 different chemical shifts in its nmr spectrum and a broad absorption
between 2500–3300 cm–1 in its infrared spectrum.
A
B
C
D
(1)
(Total 3 marks)
28.
This question concerns the nucleophilic addition reaction between a carbonyl compound and
hydrogen cyanide, HCN.
(a)
Which one of the following carbonyl compounds would produce a racemic mixture?
A
CH3COCH3
B
C2H5CHO
C
HCHO
D
C2H5COC2H5
(1)
St John's RC Comprehensive School
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(b)
Which of the following best represents the first step of the mechanism for this reaction
with an aldehyde?
R
A
R
C
C+
O
H
H
R
R
B
C
H
O
N:)
R
C
C
H
H
CN
R
O–
O
C
–
(:C
O–
C
–
(:C
N:)
H
R
CN
R
C
D
O–
H
O H
C N
OH
C+
+ –CN
H
(1)
(Total 2 marks)
St John's RC Comprehensive School
55
29.
This question concerns the formation of a polymer.
(a)
Which one of the following is a possible formula of the repeat unit of a polymer formed
from ethane-1,2-diol and benzene-1,4-dicarboxylic acid.
O
C O CH2 CH2 O
A
C
O
OH
C O CH2
CH2 O
H
B
C
OH
O
C
O CH2 CH2 O
C
C
O
O CH2 CH2 O
D
HO
H
C
C
H
OH
(1)
(b)
What type of reaction is this?
A
addition
B
condensation
C
dehydration
D
neutralisation
(1)
(Total 2 marks)
St John's RC Comprehensive School
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30.
This question is about the pineapple flavouring used in sweets. It is an ester with the formula
C3H7COOCH3, which can be broken down into butanoic acid and methanol when mixed with
hydrochloric acid.
The following equilibrium is set up:
C3H7COOCH3(l) + H2O(l)
(a)
C3H7COOH(l) + CH3OH(l)
Give the name of this ester.
.....................................................................................................................................
(1)
(b)
Why does the ester have a comparatively low boiling point compared to the other three
substances in the equation?
.....................................................................................................................................
.....................................................................................................................................
.....................................................................................................................................
(1)
(c)
What is the name given to this type of reaction?
.....................................................................................................................................
(1)
St John's RC Comprehensive School
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(d)
Suggest the reasons why manufacturers choose to use the chemically manufactured
pineapple flavouring rather than the natural product and why consumers might prefer to
choose the natural product.
.....................................................................................................................................
.....................................................................................................................................
.....................................................................................................................................
.....................................................................................................................................
.....................................................................................................................................
.....................................................................................................................................
.....................................................................................................................................
.....................................................................................................................................
.....................................................................................................................................
.....................................................................................................................................
.....................................................................................................................................
.....................................................................................................................................
.....................................................................................................................................
.....................................................................................................................................
(4)
St John's RC Comprehensive School
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(e)
In an experiment, 10.2 g (0.10 mol) of the ester was mixed with 18 cm3 of 1.0 mol dm–3
hydrochloric acid and left until equilibrium had been reached. The hydrochloric acid acts
as a catalyst and contains 18 g (1 mol) of water. At equilibrium, 4.4 g of butanoic acid
was found to be present.
Molar mass of butanoic acid = 88 g; assume the total volume at equilibrium is 30 cm3.
Give the expression for the equilibrium constant, Kc, for this equilibrium and calculate its
value. Explain why it has no units.
.....................................................................................................................................
.....................................................................................................................................
.....................................................................................................................................
(5)
(Total 12 marks)
31.
In moths a pheromone, P, acts as an attractant for the opposite sex. P has the molecular formula
C7H12O.
What can be deduced about the structure of P from the following information?
(a)
(i)
1 mole of P reacts with 1 mole of Br2 molecules to form a compound with the
formula C7H12OBr2.
...........................................................................................................................
...........................................................................................................................
(1)
St John's RC Comprehensive School
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(ii)
When lithium tetrahydridoaluminate is reacted with P a compound with the
formula C7H14O is formed.
...........................................................................................................................
...........................................................................................................................
(1)
(iii)
P forms an orange precipitate with 2,4-dinitrophenylhydrazine.
...........................................................................................................................
(1)
(iv)
When P is heated with Fehling’s or Benedict’s solution, the solution remains blue.
...........................................................................................................................
...........................................................................................................................
(1)
(v)
P is a Z-isomer.
...........................................................................................................................
...........................................................................................................................
...........................................................................................................................
...........................................................................................................................
(1)
St John's RC Comprehensive School
60
(b)
What does the following physical data tell you about the structure of P? Use your Data
booklet where necessary.
(i)
The infrared spectrum of P has the following absorptions at wavenumbers above
1600 cm–1.
3060 cm–1
2920 cm–1
1690 cm–1
1660 cm–1
...........................................................................................................................
...........................................................................................................................
...........................................................................................................................
...........................................................................................................................
...........................................................................................................................
(3)
(ii)
The nmr spectrum does not have a peak corresponding to a chemical shift, , of
between 9 and 10.
...........................................................................................................................
...........................................................................................................................
...........................................................................................................................
(1)
St John's RC Comprehensive School
61
(iii)
The mass spectrum showed the presence of peaks at mass/charge ratios of 15 and
29, but no peak at 43.
...........................................................................................................................
...........................................................................................................................
...........................................................................................................................
...........................................................................................................................
...........................................................................................................................
...........................................................................................................................
(3)
(c)
Given that P has a straight chain of carbon atoms in its formula, use the information you
have deduced above to suggest a displayed formula for the pheromone P.
(2)
(d)
How could you use a purified sample of the orange precipitate in (a)(iii) to confirm the
formula of P?
.....................................................................................................................................
.....................................................................................................................................
.....................................................................................................................................
.....................................................................................................................................
.....................................................................................................................................
(2)
(Total 16 marks)
St John's RC Comprehensive School
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32.
Which of the following isomers of C4H10O has a chiral centre?
A
Butan-1-ol
B
Butan-2-ol
C
2-methylpropan-1-ol
D
2-methylpropan-2-ol
(Total 1 mark)
33.
When the colourless liquid chlorobenzene is shaken with bromine water, the chlorobenzene
becomes a yellow orange colour. What is the interpretation of this?
A
an addition compound of chlorobenzene and bromine has formed.
B
the chlorine atom has been replaced by a bromine atom.
C
a hydrogen atom has been replaced by a bromine atom.
D
the bromine is more soluble in chlorobenzene than in water.
(Total 1 mark)
34.
What class of organic compound has a characteristic smell and gives a solution in water with a
pH of about 10?
A
arene
B
amine
C
aldehyde
D
carboxylic acid
(Total 1 mark)
St John's RC Comprehensive School
63
35.
The substance of formula (OCH2CH2OOCC6H4COOCH2CH2OOCC6H4CO)n is a
A
polyester
B
natural oil or fat
C
detergent
D
protein
(Total 1 mark)
36.
The optical isomers of alanine, CH3CH(COOH)NH2
A
have different melting points
B
rotate the plane of plane polarised light in opposite directions
C
react at different rates with ethanoyl chloride, CH3COCl
D
both occur naturally in protein molecules
(Total 1 mark)
37.
This question is about the following organic compounds:
A
Benzene, C6H6
B
Glycine, NH2CH2COOH
C
Propene, CH3CHCH2
D
Propanone, CH3COCH3
Select, from A–D, the compound which would
(a)
be a solid at room temperature
A
B
C
D
(1)
St John's RC Comprehensive School
64
(b)
give a salt by reaction with sodium hydroxide
A
B
C
D
(1)
(c)
give a sulfonic acid by reaction with fuming sulfuric acid
A
B
C
D
(1)
(d)
form a precipitate when reacted with 2,4-dinitrophenylhydrazine
A
B
C
D
(1)
(Total 4 marks)
St John's RC Comprehensive School
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