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CIE A LEVELS CHEMISTRY
PAPER 5
PAST YEAR
QUESTIONS (FROM 2014 – 2018)
Prepared by Ms. Chuk WY
(012 – 221 8626)
MARK SCHEME
2
About Ms Chuk WY
She has 14 years of experience in teaching Chemistry.
She has taught CIE A Levels Chemistry in Taylor's
College for 9 years and has consistently helped many
students to achieve excellent results in Chemistry.
If you need any assistance on Chemistry topics, feel free
to contact her at 012-221 8626 for individual or group
classes.
Individual / Group Tuition Contact
Ms Chuk WY
(012 – 221 8626)
CONTENT
Year Question
May June 2014 Paper 51 Q1: To confirm the molar quantities of magnesium oxide,
nitrogen(IV) oxide and oxygen produced agree with the
equation for the thermal decomposition of magnesium
nitrate(V).
Q2: To investigate how the cell potential of a cell containing a
metal, M, in contact with an aqueous solution of its ions,
Mn+(aq) (where n = 1, 2 or 3), changed as Mn+(aq) was diluted.
May June 2014 Paper 52 Q1: To plan an experiment, using a titration with sulfuric acid,
to determine the value of the partition coefficient of ammonia
between water and trichloromethane at room temperature.
Q2: To measure order of reaction by using concentration
against time graph.
(NO oxidise by ozone in the atmosphere to form NO2)
Oct Nov 2014 Paper 51 Q1: To confirm the composition of the solder by adding
reagents and then extracting from the mixture in sequence.
Q2: To determine the acid dissociation constant, Ka, of a weak
monoprotic acid, HA from the measurement of the pH change
that occurs when it is titrated with an aqueous solution of
sodium hydroxide.
Oct Nov 2014 Paper 53 Q1: To plan experiments that will enable you to determine the
value of the enthalpy change for the reaction of 1 mol of
magnesium with excess aqueous aluminium ions.
Q2: To determine the solubility product of nickel(II) iodate by
mixing different amount of solid potassium iodate(V) to
aqueous solution of nickel(II) sulfate
May June 2015 Paper 51 Q1: To determine the solubility of Mg(HCOO)2 by titrating
magnesium methanoate against aqueous potassium
manganate(VII).
Q2: To determine the Kc of a mixture of iodine and hydrogen
gas reacts to form an equilibrium with gaseous hydrogen iodine
May June 2015 Paper 52 Q1: This question concerns electrolysis of different compounds.
(Electrolysis of dilute sulfuric acid, potassium butanedioate)
[pH curve]
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Q2: To identify a monoprotic (monobasic) hydroxycarboxylic
acid, HX, by the carrying out this experiment:
25.0 cm3 of an aqueous solution of HX is titrated against
0.0500 mol dm–3 aqueous sodium carbonate.
Oct Nov 2015 Paper 51 Q1: To determine the relative molecular mass, Mr, of a small
sample of a volatile liquid by measuring its mass and then
heating to vaporise it to obtain its volume as a gas.
Q2: To determine the concentration of HCl by measuring the
temperature change of the reaction between HCl and various
masses of solid Ba(OH)2.
Oct Nov 2015 Paper 53 Q1: To compare the rate of the reaction between aqueous
hydroxide ions and chlorobutane, bromobutane and iodobutane.
Q2: To determine the Kc of an equilibrium between N2O4(g)
and NO2(g)
Feb Mac 2016 Paper 52 Q1: To determine the order of reaction with respect to iodine
(Reaction between aqueous propanone and aqueous iodine)
Q2: To determine the enthalpy change of combustion of ethanol
May June 2016 Paper 51 Q1: To determine the relative atomic mass of lithium by
measuring the volume of hydrogen produced from a small
amount of lithium.
Q2: To determine the activation energy for the reaction of Mg
with aqueous hydrogen ions. (Formula given)
May June 2016 Paper 52 Q1: The reaction of three different metals (magnesium, iron and
zinc) with aqueous copper(II) sulfate. Experiment is plan to
investigate whether there is a relationship between their cell
potential values and their enthalpy changes of reaction, ∆Hr.
Q2: To determine the relative molecular mass of volatile
liquids. (Formula given)
Oct Nov 2016 Paper 51 Q1: To determine the concentration of chloride ions in solution
by titration with aqueous silver nitrate of known concentration.
Q2: To determine the value of k by using the experimentally
determined values of optical rotation during the hydrolysis of
sucrose. (Formula given)
Oct Nov 2016 Paper 52 Q1: To determine the concentration of metal ions in solution,
such as Zn2+(aq) by titrations using ethylenediaminetetraacetic
acid (EDTA).
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Q2: To determine the order of reaction by measuring the
volume of gas produced over time
(Hydrolysis of Benzenediazonium chloride, C6H5N2Cl forming
phenol, nitrogen gas and hydrochloric acid.)
Feb Mac 2017 Paper 52 Q1: To determine the enthalpy change of reaction for the
decomposition of sodium hydrogencarbonate.
Q2: To determine the formula of the complex ion formed
between aqueous iron(III) ions, Fe3+(aq), and aqueous 2-
hydroxybenzoate ions, C6H4(OH)CO2–, by using colorimetry.
May June 2017 Paper 51 Q1: To determine the enthalpy change when anhydrous calcium
chloride dissolves in distilled water.
Q2: To determine the specific rotation of sucrose, [α] with
solutions of different concentrations of sucrose at 20 °C by
using polarimeter. (Formula given)
May June 2017 Paper 52 Q1: To find out if Dalton’s law is true for three oxides of lead
by using methane gas to reduce the heated lead oxides to lead.
Q2: To analyse the manganese content of steel by comparing
the absorbance of a solution of MnO4–(aq) prepared from a
sample of steel, with the absorbance of solutions of known
concentrations of MnO4–(aq) using a spectrophotometer.
Oct Nov 2017 Paper 51 Q1: To plan a series of experiments to determine the effect of
changing the concentration of iodide ions on the rate of
reaction.
Q2: To determine the Faraday constant by measuring the
production of hydrogen gas over time.
Oct Nov 2017 Paper 52 Q1: To determine the percentage of copper(II) carbonate in a
sample of Verdigris by using the reaction of verdigris with
excess dilute hydrochloric acid.
Q2: To investigate the ability of activated charcoal to adsorb a
blue dye from an aqueous solution. (Formula given)
Feb Mac 2018 Paper 52 Q1: To determine the Mr of unknown compound X by using
Beckmann thermometer to determining the different in freezing
point of solutions. (Formula given)
Q2: To determine the exact percentage by mass of FeSO4.7H2O
present in a sample of lawn sand by using titration
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May June 2018 Paper 51 Q1: To determine the Faraday constant by electrolysis
Q2: To investigates the reaction between benzenediazonium
ion, C6H5N2+, and water by measuring the volume of nitrogen
gas produced at regular time intervals.
May June 2018 Paper 52 Q1: To investigate how much of a particular salt solution was
required to fully precipitate all the Fe2O3 sol in a 1000 cm3
sample.
Q2: To determine the boiling point constant, Kb, for water by
using anhydrous glucose, C6H12O6, as the solute.
[Vapour pressure] (Formula given)
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CONTENT
Electrochemistry
Jun 2014 Paper 51 Q2
Nov 2008 Paper 5 Q2
June 2015 Paper 52 Q1 (Electrolysis)
June 2016 Paper 52 Q1 (Relationship between Ecell and ∆H)
Nov 2017 Paper 51 Q2 (Determine Faraday constant)
June 2018 Paper 51 Q1 (Determine Faraday constant)
Ionic Equilibrium
Nov 2014 Paper 51 Q2 (Determine the Ka)
June 2015 Paper 52 Q2 ( pH curve)
Nov 2014 Paper 53 Q2 (Solubility product)
Kc
June 2015 Paper 51 Q2
Oct 2015 Paper 53 Q2
Partition Coefficient
Jun 2014 Paper 52 Q1
Nov 2010 Paper 53 Q2
Order of Reaction
Jun 2014 Paper 52 Q2
Mac 2016 Paper 52 Q1
Nov 2016 Paper 52 Q2
Ease of Hydrolysis
Oct 2015 Paper 53 Q1
Solubility
June 2015 Paper 51 Q1
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Titration
Nov 2016 Paper 51 Q1
Nov 2016 Paper 52 Q1
Thermal Decomposition
Jun 2014 Paper 53 Q1
Enthalpy Change
June 2017 Paper 51 Q1 (Enthalpy change of solution)
Nov 2014 Paper 53 Q1 (Enthalpy change of reaction)
Mac 2016 Paper 52 Q2 (Enthalpy change of combustion)
Mac 2017 Paper 52 Q1 (Enthalpy change of reaction)
Rate of Reaction
Nov 2017 Paper 51 Q1 (The effect of concentration)
June 2018 Paper 51 Q2 (Gas product against time graph)
Vapor Pressure
Jun 2010 Paper 52 Q1
June 2018 Paper 52 Q2
To determine Mr or Ar
Nov 2015 Paper 51 Q1 (Mr)
June 2016 Paper 51 Q1 (Ar)
June 2016 Paper 52 Q2 (Mr-formula given)
Mac 2018 Paper 52 Q1 (Mr-formula given)
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This document consists of 10 printed pages and 2 blank pages.
[Turn overIB14 06_9701_51/6RP© UCLES 2014
*0139125346*
READ THESE INSTRUCTIONS FIRST
Write your Centre number, candidate number and name on all the work you hand in.Write in dark blue or black pen.You may use an HB pencil for any diagrams or graphs.Do not use staples, paper clips, glue or correction fl uid.DO NOT WRITE IN ANY BARCODES.
Answer all questions.Electronic calculators may be used.You may lose marks if you do not show your working or if you do not use appropriate units.Use of a Data Booklet is unnecessary.
At the end of the examination, fasten all your work securely together.The number of marks is given in brackets [ ] at the end of each question or part question.
CHEMISTRY 9701/51
Paper 5 Planning, Analysis and Evaluation May/June 2014
1 hour 15 minutes
Candidates answer on the Question Paper.
No Additional Materials are required.
Cambridge International ExaminationsCambridge International Advanced Level
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1 When magnesium nitrate(V) is heated, it decomposes to form magnesium oxide, nitrogen(IV) oxide and oxygen.
Nitrogen(IV) oxide is an acidic gas that reacts readily and completely with alkalis.
You are to plan a single experiment to confi rm that the molar quantities of magnesium oxide, nitrogen(IV) oxide and oxygen produced agree with the equation for the thermal decomposition of magnesium nitrate(V).
The following information gives some of the hazards associated with nitrogen(IV) oxide.
Nitrogen(IV) oxide must not be inhaled. A large dose can be fatal and smaller quantities can have severe effects on breathing, particularly for people who suffer from asthma.
You are provided with anhydrous magnesium nitrate(V) and have access to the usual laboratory equipment and reagents.
(a) (i) Write an equation for the thermal decomposition of magnesium nitrate(V).
....................................................................................................................................... [1]
(ii) Calculate the mass of magnesium oxide and volumes of nitrogen(IV) oxide and oxygen produced under room conditions when 1 mole of magnesium nitrate(V) is heated.
[Ar: O, 16.0; Mg, 24.3]
You should assume that one mole of any gas occupies 24.0 dm3 under room conditions.
[1]
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(b) (i) Draw and label a diagram of the apparatus and experimental set-up you would use. The set-up needs to be capable of absorbing the nitrogen(IV) oxide and collecting the oxygen separately and in sequence.
[4]
(ii) State the volume of the gas collector to be used to collect oxygen in (i). Calculate a mass of magnesium nitrate(V) to be heated that would produce a stated volume of oxygen appropriate for the collector.
[Ar: N, 14.0; O, 16.0; Mg, 24.3]
You should assume that one mole of any gas occupies 24.0 dm3 under room conditions.
[1]
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(c) List the measurements you would make when carrying out the experiment.
....................................................................................................................................................
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(d) (i) How could you make sure that the magnesium nitrate(V) had completely decomposed in the experiment?
.............................................................................................................................................
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(ii) To make sure that the volume of gas measured is accurate, what should you do before taking the measurement?
.............................................................................................................................................
....................................................................................................................................... [1]
(e) Explain how you would use the results of the experiment to confi rm that the decomposition had occurred according to the molar ratios in the equation.
....................................................................................................................................................
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(f) What precautions would you take to make sure that the experiment could be performed safely?
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[Total: 15]
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2 An experiment was set up to investigate how the cell potential of a cell containing a metal, M, in contact with an aqueous solution of its ions, Mn+(aq) (where n = 1, 2 or 3), changed as Mn+(aq) was diluted.
Since a standard hydrogen half-cell was not available, a standard half-cell consisting of silver in contact with a 1 mol dm–3 solution of silver ions was used to connect to the half-cell with M in contact with Mn+(aq).
V
salt bridgemetal M
electrode
Mn+(aq) ions 1 mol dm–3
Ag+(aq) ions
silverelectrode
The metal electrodes of the two half-cells were connected via a voltmeter, reading to two decimal places. This was used to measure the cell potential of the cell.
The cell potential was measured for various concentrations of Mn+(aq) and the results obtained are shown in the table below.
(a) Complete the third column of the table below. Give each answer to two decimal places.
concentration ofMn+(aq) / mol dm–3
cell potential/ V log [Mn+(aq)]
5.00 × 10–1 0.94
1.00 × 10–1 0.96
4.00 × 10–2 0.97
1.00 × 10–2 0.99
5.00 × 10–3 1.00
2.00 × 10–3 1.01
8.00 × 10–4 1.02
2.00 × 10–4 1.04[2]
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(b) Plot a graph to show the relationship between log [Mn+(aq)] and the cell potential measured and draw the line of best fi t.
1.04
1.03
1.02
1.01
1.00
0.99
0.98
0.97
0.96
0.95
0.94
0.93
0.92– 4.5 – 4.0 –3.5 –3.0 –2.5 –2.0 –1.5 –1.0 –0.5 0.0
cell potential / V
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(c) Are there any anomalous points on your graph? If so, circle those points. Give a reason for your answer.
....................................................................................................................................................
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.............................................................................................................................................. [2]
(d) It is known that the cell potential of a cell, E, is related to the standard electrode potential, E o, by the equation:
E = E o –0.06 log [Mn+(aq)]
n
(i) Use your graph to determine the charge, n, of the Mn+ ions. Draw appropriate lines on your graph to enable you to calculate its slope and show in the space below, how n was calculated.
[3]
(ii) Use your graph to determine the standard electrode potential, E o, of the cell.
.............................................................................................................................................
....................................................................................................................................... [1]
(e) The standard electrode potential for silver is +0.80 V. Calculate the standard electrode potential for the metal, M. Use the data given on page 12 to
suggest the identity of M.
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(f) Write an overall equation for the cell reaction which is taking place.
.............................................................................................................................................. [1]
(g) The solutions contained in the two half-cells must be connected using a salt bridge.
(i) Why is a salt bridge necessary?
.............................................................................................................................................
....................................................................................................................................... [1]
(ii) Which (if any) of the following salts would be suitable to use in the salt bridge:
potassium chloride, potassium nitrate, potassium sulfate?
If you consider any to be unsuitable, explain why.
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[Total: 15]
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Permission to reproduce items where third-party owned material protected by copyright is included has been sought and cleared where possible. Everyreasonable effort has been made by the publisher (UCLES) to trace copyright holders, but if any items requiring clearance have unwittingly been included the publisher will be pleased to make amends at the earliest possible opportunity.
Cambridge International Examinations is part of the Cambridge Assessment Group. Cambridge Assessment is the brand name of University of Cambridge Local Examinations Syndicate (UCLES), which is itself a department of the University of Cambridge.
E o in decreasing order of oxidising power
Electrode reaction E o / V
F2 + 2e– 2F– +2.87 S2O8
2– + 2e– 2SO42– +2.01
H2O2 + 2H+ + 2e– 2H2O +1.77 MnO4
– + 8H+ + 5e– Mn2+ + 4H2O +1.52 PbO2 + 4H+ + 2e– Pb2+ + 2H2O +1.47 Cl 2 + 2e– 2Cl – +1.36 Cr2O7
2– + 14H+ + 6e– 2Cr3+ + 7H2O +1.33 Br2 + 2e– 2Br
– +1.07 NO3
– + 2H+ + e– NO2 + H2O +0.81 Ag+ + e– Ag +0.80 Fe3+ + e– Fe2+ +0.77 I2 + 2e– 2I– +0.54 O2 + 2H2O + 4e– 4OH– +0.40 Cu2+ + 2e– Cu +0.34 SO4
2– + 4H+ + 2e– SO2 + 2H2O +0.17 Sn4+ + 2e– Sn2+ +0.15 S4O6
2– + 2e– 2S2O32– +0.09
2H+ + 2e– H2 0.00 Pb2+ + 2e– Pb –0.13 Sn2+ + 2e– Sn –0.14 Fe2+ + 2e– Fe –0.44 Zn2+ + 2e– Zn –0.76 Mg2+ + 2e– Mg –2.38 Ca2+ + 2e– Ca –2.87 K+ + e– K –2.92
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This document consists of 9 printed pages and 3 blank pages.
[Turn overIB14 06_9701_52/7RP© UCLES 2014
*5820052839*
READ THESE INSTRUCTIONS FIRST
Write your Centre number, candidate number and name on all the work you hand in.Write in dark blue or black pen.You may use an HB pencil for any diagrams or graphs.Do not use staples, paper clips, glue or correction fl uid.DO NOT WRITE IN ANY BARCODES.
Answer all questions.Electronic calculators may be used.You may lose marks if you do not show your working or if you do not use appropriate units.Use of a Data Booklet is unnecessary.
At the end of the examination, fasten all your work securely together.The number of marks is given in brackets [ ] at the end of each question or part question.
CHEMISTRY 9701/52
Paper 5 Planning, Analysis and Evaluation May/June 2014
1 hour 15 minutes
Candidates answer on the Question Paper.
No Additional Materials are required.
Cambridge International ExaminationsCambridge International Advanced Level
Prepared by CHUK WY (012-221 8626)
17
CHUK WY
2
9701/52/M/J/14© UCLES 2014
1 The liquids trichloromethane and water separate into two immiscible layers when shaken together and allowed to stand.
Ammonia can dissolve in both of these layers. The distribution of ammonia between these two solvents is called partition, where the concentration of ammonia in each solvent will be different. The partition coeffi cient represents the ratio of the distribution.
You are to plan an experiment, using a titration with sulfuric acid, to determine the value of the partition coeffi cient of ammonia between water and trichloromethane at room temperature.
The following information gives some of the hazards associated with trichloromethane and ammonia.
Trichloromethane:Anaesthetic if inhaled. Dangerously irritating to the respiratory system.
Ammonia:An aqueous solution with a concentration of less than 3 mol dm–3 may cause harm to eyes or in a cut. At greater concentrations aqueous ammonia should not be inhaled and it causes irritation to the eyes and skin.
You are provided with the following.
● trichloromethane ● aqueous ammonia of concentration 5.00 mol dm–3
● sulfuric acid, of concentration 0.500 mol dm–3
● distilled water for dilution of aqueous ammonia
(a) Explain why ammonia is likely to be more soluble in water than in trichloromethane.
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.............................................................................................................................................. [2]
(b) Defi ne the partition coeffi cient, Kpartition, for ammonia between water and trichloromethane. State whether the partition coeffi cient you have defi ned will be greater or less than 1.
[1]
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