Unit H432-01 Periodic Table Elements And Physical .

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A Level Chemistry AH432/01 Periodic table, elements and physicalchemistrySample Question PaperDate – Morning/AfternoonVersion 2.0Time allowed: 2 hours 15 minutesYou may use: a scientific or graphical calculatorENYou must have: the Data Sheet for Chemistry A*First nameLast CTIONS Use black ink. You may use an HB pencil for graphs and diagrams. Complete the boxes above with your name, centre number and candidate number. Answer all the questions. Where appropriate, your answers should be supported with working. Marks maybe given for a correct method even if the answer is incorrect. Write your answer to each question in the space provided. Additional paper may be used if required but you must clearly show your candidatenumber, centre number and question number(s). Do not write in the bar codes.INFORMATION The total mark for this paper is 100. The marks for each question are shown in brackets [ ]. Quality of extended responses will be assessed in questions marked with an asterisk (*). This document consists of 28 pages. OCR 2016[601/5255/2] DC ( )H432/01Turn over

2SECTION AYou should spend a maximum of 20 minutes on this section.Answer all the questions.Which row shows the atomic structure of 55Mn2 528EN1Your answerThe Group 2 elements react with water, forming a solution and a gas.ECIM2[1]Which statement is correct?The reactivity of the elements decreases down Group 2.BThe pH of the solution formed increases down Group 2.CThe reaction is a neutralisation.DThe equation for the reaction of strontium with water is:SPA2Sr 2H2O 2SrOH H2Your answer[1] OCR 2016H432/01

33Chloroethene, CH2 CHCl, is prepared in the presence of a solid catalyst using the equilibriumreaction below.CH2ClCH2Cl(g) H 51 kJ mol–1CH2 CHCl(g) HCl(g)Which change would result in an increased equilibrium yield of chloroethene?Aincreasing the pressureBincreasing the surface area of the catalystCincreasing the temperatureDuse of a homogeneous catalystYour answerThe table below shows enthalpy changes of formation, fH.CompoundTiCl4(l) fH / kJ mol �92What is the value of the enthalpy change of reaction, rH, for the reaction in the following equation?TiCl4(l) 2H2O(l) TiO2(s) 4HCl(g)–63 kJ mol–1B–53 kJ mol–1C 53 kJ mol–1D 63 kJ mol–1SPAYour answer[1] OCR 2016H432/01Turn over

45Zinc reacts with copper(II) sulfate solution, CuSO4(aq).Which apparatus could be used to determine the effect of the concentration of CuSO 4(aq) on therate of reaction?AbalanceBgas syringeCcolorimeterDpH meterYour answer[1]The boiling point of hydrogen bromide is –67 ºC.The boiling point of hydrogen iodide is –34 ºC.EN6The different boiling points can be explained in terms of the strength of bonds or interactions.ECIMWhich bonds or interactions are responsible for the higher boiling point of hydrogen iodide?covalent bondsBhydrogen bondsCpermanent dipole–dipole interactionsDinduced dipole–dipole interactionsSPAYour answer7[1]The 1st to 8th successive ionisation energies, in kJ mol 1, of an element in period 3 are:1012190329124957627421 26925 39829 855What is the element?AAlBSiCPDSYour answer[1] OCR 2016H432/01

58Using the graph, what is the value of the pre-exponential factor, A, for the decomposition of N2O5?3.45 s 1B31.5 s 1C1.04 105 s 1D4.79 1013 s 1SPAECIMEN2N2O5(g) 4NO(g) O2(g)Your answer9[1]A solution of propanoic acid, CH3CH2COOH, has a pH of 2.89 at 25 C.What is [H ] in this solution?A1.7 10 6 mol dm 3B4.6 10 4 mol dm 3C1.3 10 3 mol dm 3D0.46 mol dm 3Your answer[1] OCR 2016H432/01Turn over

610The lattice enthalpy of calcium chloride can be calculated using three of the enthalpychanges below.Which enthalpy change is not required?Aenthalpy change of solution of calcium chlorideBenthalpy change of hydration of Cl ionsCenthalpy change of formation of calcium chlorideDenthalpy change of hydration of Ca2 ionsYour answer[1]AH2SO4 8HI H2S 4I2 4H2OBS O2 SO2CS2O32 2H SO2 S H2ODS 6HNO3 H2SO4 6NO2 2H2OYour answer[1]NO(g), H2(g), N2(g) and H2O(g) exist in equilibrium:SP12ENWhich redox reaction contains the largest change in oxidation state for sulfur?ECIM112NO(g) 2H2(g)N2(g) 2H2O(g)At room temperature and pressure, the equilibrium lies well to the right-hand side.Which of the following could be the equilibrium constant for this equilibrium?A1.54 10 3 mol dm 3B6.50 102 mol dm 3C1.54 10 3 dm3 mol 1D6.50 102 dm3 mol 1Your answer[1] OCR 2016H432/01

713Copper(II) ions form an aqueous complex ion, X, with chloride ions.Which statement about X is true?AX has optical isomersBX has a square planar shapeCX has the formula CuCl42 DX has a yellow colourYour answer[1]Two tests are carried out on an aqueous solution of copper(II) sulfate, CuSO4(aq).Test 1: Addition of potassium iodide solutionTest 2: Addition of barium chloride solutionWhich of the following statements is/are true?EN14ECIM1: Test 1 produces an off-white precipitate and a brown solution.2: Test 2 produces a white precipitate.3: Test 1 and Test 2 are both redox reactions.1, 2 and 3BOnly 1 and 2COnly 2 and 3DOnly 1SPAYour answer[1] OCR 2016H432/01Turn over

815Two students set up the equilibrium system below.CH3COOC2H5(l) H2O(l)C2H5OH(l) CH3COOH(l)The students titrated samples of the equilibrium mixture with sodium hydroxide, NaOH(aq), todetermine the concentration of CH3COOH.The students used their results to calculate a value for Kc.The students’ values for Kc were different.Which of the reason(s) below could explain why the calculated values for Kc were different?1: Each student carried out their experiment at a different temperature.2: Each student used a different concentration of NaOH(aq) in their titration.1, 2 and 3BOnly 1 and 2COnly 2 and 3DOnly 1SPYour answerECIMAEN3: Each student titrated a different volume of the equilibrium mixture. OCR 2016H432/01[1]

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10SECTION BAnswer all the questions.16Ammonia is a gas with covalently-bonded molecules consisting of nitrogen and hydrogen atoms.(a)Show the electron configuration of a nitrogen atom using ‘electron-in-box’ diagrams.Label each sub-shell.1s Ammonia can be made from the reaction of nitrogen and hydrogen in the Haber process.N2(g) 3H2(g)ECIM(b)EN[2]2NH3(g)ΔH –92 kJ mol 1 Equation 1What effect will increasing the temperature have on the composition of the equilibrium mixture andon the value of the equilibrium constant?SPExplain your answer. OCR 2016H432/01[2]

11(c)A chemist mixes together 0.450 mol N2 with 0.450 mol H2 in a sealed container.The mixture is heated and allowed to reach equilibrium.At equilibrium, the mixture contains 0.400 mol N2 and the total pressure is 500 kPa.Calculate Kp.ECIMENInclude units in your answer.SPKp units [5] OCR 2016H432/01Turn over

12(d) A chemical company receives an order to supply 1.96 1010 dm3 of ammonia at room temperatureand pressure. The Haber process produces a 95.0% yield.Calculate the mass of hydrogen, in tonnes, required to produce the ammonia.ENGive your answer to three significant figures.(e)ECIMrequired mass of hydrogen tonnes [3](i) Hydrazine, N2H4, is used as a rocket fuel. Hydrazine can be prepared from the reaction ofammonia with sodium chlorate(I). There are two other products in the reaction.SPWrite an equation for this reaction.[1](ii) Using the electron pair repulsion theory, draw a 3-D diagram of a molecule of hydrazine.Predict the H–N–H bond angle around each nitrogen atom.H–N–H bond angle: OCR 2016H432/01[2]

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1417Iodine monochloride, ICl, can react with hydrogen to form iodine.2ICl H2 2HCl I2This reaction was carried out several times using different concentrations of ICl or H2.The initial rate of each experiment was calculated and the results are shown below.Initial concentrations are shown for each experiment.[H2] / mol dm–3Rate / mol dm–3 s–1Experiment 10.2500.5002.04 10 2Experiment 20.5000.5004.08 10 2Experiment 30.1250.2505.10 10 3Calculate the rate constant, k, for this reaction. Include units in your answer.SPECIMEN(a) (i)[ICl] / mol dm–3k units [4](ii) Calculate the rate of reaction when ICl has a concentration of 3.00 10–3 mol dm–3 and H2has a concentration of 2.00 10–3 mol dm–3.rate mol dm 3 s 1 OCR 2016H432/01[1]

15(b) Reaction rates can be increased or decreased by changing the temperature of the reaction. Fig. 17.1below shows the energy distribution of the reactant molecules at 25 C.number ofmoleculesenergyFig. 17.1ENDraw a second curve on Fig. 17.1, to represent the distribution of the same number of molecules at ahigher temperature.ECIMUse your curve to explain how increasing the temperature increases the rate of reaction. [2]SP . OCR 2016H432/01Turn over

1618A student is asked to calculate ΔG at 25 ºC for the combustion of butan-1-ol. The teacher provides twopieces of information. The equation for the combustion of butan-1-ol.CH3(CH2)3OH(l) 6O2(g) 4CO2(g) 5H2O(l) Equation 2Standard entropies of butan-1-ol, oxygen, carbon dioxide and water.So/ J K–1 PECIMENThe student carries out an experiment using the apparatus below and obtains the following results.The specific heat capacity of water is 4.18 J g–1 K–1. OCR 2016Mass of burner and butan-1-ol before burning / g98.997Mass of burner and butan-1-ol after burning / g98.738Initial temperature / ºC18.5Maximum temperature reached / ºC39.0H432/01

17SPECIMENUse the information on the previous page to calculate ΔG, in kJ mol 1, for the combustion ofbutan-1-ol according to Equation 2 at 25 C. OCR 2016ΔG kJ mol 1H432/01[7]Turn over

1819This question is about the chemistry of the elements in Group 2 and the halogens.(a) A student prepares an aqueous solution of magnesium chloride by reacting magnesium with excesshydrochloric acid.Write an equation, including state symbols, for this reaction and state the observation(s) the studentshould make whilst carrying out this experiment.equation: .observation(s): .[2](b) Lattice enthalpies give an indication of the strength of ionic bonding.Explain your answer.ENHow would the lattice enthalpies of magnesium chloride and calcium chloride differ?ECIM SP OCR 2016H432/01[3]

19(c)The table below shows the enthalpy changes that are needed to determine the lattice enthalpyof magnesium chloride, MgCl2.LetterEnergy /kJ mol–1A1st electron affinity of chlorine–349B1st ionisation energy of magnesium 736Catomisation of chlorine 150Dformation of magnesium chloride–642Eatomisation of magnesiumF2nd ionisation energy of magnesiumGlattice enthalpy of magnesium chloride 76 1450On the cycle below, write the correct letter in each box.SPECIMEN(i)Enthalpy change[3](ii) Use the Born–Haber cycle to calculate the lattice enthalpy of magnesium chloride.lattice enthalpy kJ mol–1 OCR 2016H432/01[2]Turn over

20(d)* Describe and explain the relative reactivity of the halogens, chlorine, bromine and iodine, in theirredox reactions with halides, using reactions on a test-tube scale.Include reaction equations and observations in your answer.[6] . . . . . .EN ECIM . . . .SP . . Additional answer space if required. . . . . . . OCR 2016H432/01

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2220A student investigates the reactions of two weak monobasic acids: 2-hydroxypropanoic acid,CH3CH(OH)COOH, and butanoic acid, CH3CH2CH2COOH.(a) The student wants to prepare a standard solution of 2-hydroxypropanoic acid that has a pH of 2.19.Plan how the student could prepare 250 cm3 of this standard solution from solid 2-hydroxypropanoicacid.In your answer you should provide detail of the practical procedure that would be carried out,including appropriate quantities and necessary calculations.ECIMENKa for 2-hydroxypropanoic acid is 1.38 10–4 mol dm–3 at 25 C. .SP . . . . . OCR 2016H432/01[8]

23(b) 2-Hydroxypropanoic acid is a slightly stronger acid than butanoic acid. The two acids are mixedtogether and an acid–base equilibrium is set up.Suggest the equilibrium equation and identify the conjugate acid–base pairs.CH3CH(OH)COOH CH3CH2CH2COOH [2](c) To prepare a buffer solution, 75.0 cm3 of 0.220 mol dm–3 butanoic acid is reacted with 50.0 cm3 of0.185 mol dm–3 sodium hydroxide.ENKa for butanoic acid is 1.5 10–5 mol dm–3 at 25 C.(i) Calculate the pH of 0.185 mol dm–3 sodium hydroxide at 25 C.ECIMGive your answer to two decimal places.pH [2]pH [4]SP(ii) Calculate the pH of the buffer solution at 25 C.Give your answer to two decimal places. OCR 2016H432/01Turn over

2421Table 21.1 below gives the standard electrode potentials for seven redox systems.You need to use this information to answer the questions below.Redox systemEo/VEquationMnO4–(aq) 8H (aq) 5e–Mn2 (aq) 4H2O(l) 1.512Cr2O72–(aq) 14H (aq) 6e–2Cr3 (aq) 7H2O(l) 1.333Br2(aq) 2e–2Br–(aq) 1.094Ag (aq) e–Ag(s) 0.805Fe3 (aq) e–Fe2 (aq) 0.776Zn2 (aq) 2e–Zn(s)–0.767Ce3 (aq) 3e–Ce(s)–2.33EN1Table 21.1Outline an experimental setup that could be used in the laboratory to measure the standardcell potential of an electrochemical cell based on redox systems 4 and 5.ECIM(a) (i)SPIn your answer you should include details of the apparatus, solutions and the standardconditions required to measure this standard cell potential. OCR 2016H432/01[4]

25(ii) An electrochemical cell can be made based on redox systems 2 and 4.The standard cell potential is 0.53 V.State and explain the effect on the cell potential of this cell if the concentration of silver ions isincreased. [2](b) From Table 21.1, predict the oxidising agent(s) that will not oxidise Fe2 (aq) to Fe3 (aq).[1]EN (c) An aqueous solution of iron(II) bromide is mixed with an excess of acidified solution containingmanganate(VII) ions.ECIMUsing Table 21.1, give the formulae of the products of any reactions that take place. . .[2]SP OCR 2016H432/01Turn over

2622A student carries out a number of experiments on transition metal compounds.4.800 g of a green hydrated crystalline solid A are heated in a crucible to remove the water ofcrystallisation. 1.944 g of water are removed to leave 0.0180 mol of solid residue B.Solid B contains 32.8%, by mass, of the transition metal.All of B is reacted with AgNO3(aq) to form 7.695 g of a white precipitate, C.The green crystalline solid A is dissolved in water to produce a green solution containing acomplex ion, D.When aqueous sodium hydroxide is added to solution of D, a grey–green precipitate, E, is observed,which dissolves in excess aqueous sodium hydroxide to form a green solution.SPECIMEN(a) Determine the formulae of A, B, D and E. OCR 2016A D B E H432/01[9]

27(b)* Transition metal complexes often have different shapes and may form a number of stereoisomers.Describe the different shapes and the different types of stereoisomerism found in transition metalchemistry.[6]ECIMENUse suitable examples and diagrams in your answer.SP . . . . . . . . . . OCR 2016H432/01Turn over

28Additional answer space if required. . . . . . . .EN . .ECIM . . .SPEND OF QUESTION PAPERCopyright Information:OCR is committed to seeking permission to reproduce all third-party content that it uses in the assessment materials. OCR has attempted toidentify and contact all copyright holders whose work is used in this paper. To avoid the issue of disclosure of answer-related information tocandidates, all copyright acknowledgements are reproduced in the OCR Copyright Acknowledgements booklet. This is produced for each seriesof examinations and is freely available to download from our public website (www.ocr.org.uk) after the live examination series.If OCR has unwittingly failed to correctly acknowledge or clear any third-party content in this assessment material, OCR will be happy to correct itsmistake at the earliest possible opportunity.For queries or further information please contact the Copyright Team, First Floor, 9 Hills Road, Cambridge CB2 1GE.OCR is part of the Cambridge Assessment Group; Cambridge Assessment is the brand name of University of Cambridge Local ExaminationsSyndicate (UCLES), which is itself a department of the University of Cambridge. OCR 2016H432/01

day June 20XX – Morning/AfternoonENA Level Chemistry AH432/01 Periodic table, elements and physical chemistry100SPEMAXIMUM MARKCIMSAMPLE MARK SCHEMEThis document consists of 24 pagesDuration: 2 hours 15 minutes

H432/01Mark SchemeJune 20XXMARKING INSTRUCTIONSPREPARATION FOR MARKINGSCORISMake sure that you have accessed and completed the relevant training packages for on-screen marking: scoris assessor Online Training;OCR Essential Guide to Marking.2.Make sure that you have read and understood the mark scheme and the question paper for this unit. These are posted on the RM CambridgeAssessment Support Portal http://www.rm.com/support/ca3.Log-in to scoris and mark the required number of practice responses (“scripts”) and the required number of standardisation responses.CIMEN1.MARKINGSPEYOU MUST MARK 10 PRACTICE AND 10 STANDARDISATION RESPONSES BEFORE YOU CAN BE APPROVED TO MARK LIVESCRIPTS.1.Mark strictly to the mark scheme.2.Marks awarded must relate directly to the marking criteria.3.The schedule of dates is very important. It is essential that you meet the scoris 50% and 100% (traditional 50% Batch 1 and 100% Batch 2)deadlines. If you experience problems, you must contact your Team Leader (Supervisor) without delay.4.If you are in any doubt about applying the mark scheme, consult your Team Leader by telephone, email or via the scoris messaging system.2

H432/015.Mark SchemeJune 20XXWork crossed out:a.where a candidate crosses out an answer and provides an alternative response, the crossed out response is not marked and gains nomarksb.if a candidate crosses out an answer to a whole question and makes no second attempt, and if the inclusion of the answer does notcause a rubric infringement, the assessor should attempt to mark the crossed out answer and award marks appropriately.Always check the pages (and additional objects if present) at the end of the response in case any answers have been continued there. If thecandidate has continued an answer there then add a tick to confirm that the work has been seen.7.There is a NR (No Response) option. Award NR (No Response)EN6.if there is nothing written at all in the answer space-OR if there is a comment which does not in any way relate to the question (e.g. ‘can’t do’, ‘don’t know’)-OR if there is a mark (e.g. a dash, a question mark) which isn’t an attempt at the question.CIM-8.SPENote: Award 0 marks – for an attempt that earns no credit (including copying out the question).The scoris comments box is used by your Team Leader to explain the marking of the practice responses. Please refer to these commentswhen checking your practice responses. Do not use the comments box for any other reason.If you have any questions or comments for your Team Leader, use the phone, the scoris messaging system, or email.9.Assistant Examiners will send a brief report on the performance of candidates to their Team Leader (Supervisor) via email by the end of themarking period. The report should contain notes on particular strengths displayed as well as common errors or weaknesses. Constructivecriticism of the question paper/mark scheme is also appreciated.3

H432/01June 20XXFor answers marked by levels of response:Read through the whole answer from start to finish, concentrating on features that make it a stronger or weaker answer using the indicativescientific content as guidance. The indicative scientific content indicates the expected parameters for candidates’ answers, but be prepared torecognise and credit unexpected approaches where they show relevance.Using a ‘best-fit’ approach based on the science content of the answer, first decide which set of level descriptors, Level 1, Level 2 or Level 3,best describes the overall quality of the answer using the guidelines described in the level descriptors in the mark scheme.ENOnce the level is located, award the higher or lower mark.The higher mark should be awarded where the level descriptor has been evidenced and all aspects of the communication statement (initalics) have been met.In summary: CIMThe lower mark should be awarded where the level descriptor has been evidenced but aspects of the communication statement (in italics)are missing.The science content determines the level.The communication statement determines the mark within a level.Level of response questions on this paper are 19(d) and 22(b).SPE10.Mark Scheme4

H432/01AnnotationsAnnotationDO NOT ALLOWMeaningAnswers which are not worthy of creditStatements which are irrelevantALLOWAnswers that can be acceptedENIGNOREWords which are not essential to gain creditUnderlined words must be present in answer to score a markCIM()ECFError carried forwardAWAlternative wordingORAOr reverse argumentSPE11.Mark Scheme5June 20XX

H432/0112.Mark SchemeJune 20XXSubject-specific Marking InstructionsINTRODUCTION the specification, especially the assessment objectives the question paper the mark scheme.ENYour first task as an Examiner is to become thoroughly familiar with the material on which the examination depends. This material includes:CIMYou should ensure that you have copies of these materials.You should ensure also that you are familiar with the administrative procedures related to the marking process. These are set out in the OCRbooklet Instructions for Examiners. If you are examining for the first time, please read carefully Appendix 5 Introduction to Script Marking:Notes for New Examiners.SPEPlease ask for help or guidance whenever you need it. Your first point of contact is your Team Leader.6

H432/01Mark SchemeJune 20XXSECTION 1SPE12ENQuestion11111D1D1B1D1Total715Guidance

H432/01Mark SchemeJune 20XXSECTION BQuestion16 (a)AnswerMarksGuidance2ALLOW half headed arrows 2s The forward reaction is exothermic, so an increase intemperature favours the backward reaction (owtte) 2EN(b)2pFIRST CHECK THE ANSWER ON THE ANSWER LINEIF answer 2.37 10–6 kPa–2 award 5 marksIF answer 2.37 10–6 with incorrect units award 4 marksAt equilibrium,n(H2) 0.300 (mol) ANDn(NH3) 0.100 (mol) 0.400p(N2) 500 250 kPa AND0.8000.300p(H2) 500 187.5 kPa AND0.8000.100p(NH3) 500 62.5 kPa 0.800p(NH 3 )262.52Kp p(N 2 ) p(H 2 )3250 187.53SPE(c)CIM therefore there will be more N2 and H2 OR less NH3 in theequilibrium mixture, AND therefore the value of theequilibrium constant will decrease (owtte) 5ALLOW names of compoundsALLOW reactants/product instead ofcompounds2nd mark only available if deduced from 1st markALLOW ECF for 2nd markFinal answer must be correct and have thecorrect units to score all five marksALLOW calculator value for Kp correctlyrounded to three or more significant figures.If there is an alternative answer, check to seeif there is any ECF credit possible usingworking belowCorrect values substituted into correctexpression for Kp gains first three marks. 2.37 10–6 kPa–2 8

H432/01Mark SchemeAnswerFIRST CHECK THE ANSWER ON THE ANSWER LINEIF answer 2580 (tonnes) award 3 marksn(NH3) MarksGuidance3If there is an alternative answer, check to seeif there is any ECF credit possible usingworking belowALLOW 2.58 103 tonnes1.96 1010 OR 8.167 108 (mol)24ANDAW100% yield 2.063 1010 dm3 n(H2) 8.167 108 3 1.225 109 (mol) 2Amount of NH3 8.596 108 mol ANDAmount of H2 1.289 109 mol Mass of H2 2.450 109 2450 (tonnes) 1 106Mass of H2 2580 (tonnes) (ii)2NH3 NaOCl N2H4 NaCl H2O NHo107NHHH Bond angle 107 SPE(i)CIMMass of H2 for 95% yield 2450 100 2580 (tonnes)95 (e)ENQuestion(d)June 20XXALLOW 2579 (tonnes) (calculator answerrounded to nearest whole number)12Diagram must attempt to show geometry aroundthe nitrogen atom to be pyramidalALLOW 106–108 Total915

H432/01Mark SchemeAnswerFIRST CHECK THE ANSWER ON THE ANSWER LINEIF answer 0.163 dm3 mol–1 s–1 OR 0.1632 dm3 mol–1 s–1award 4 marksIF answer 0.163 OR 0.1632 with incorrect units award 3marksMarksGuidance4If there is an alternative answer, check to seeif there is any ECF credit possible usingworking belowOrder w.r.t. ICl 1 and order w.r.t H2 1 Both orders 1 markrate k[ICl][H2] Correct rate equation or rearranged form 1mark(ii) rate k[ICl][H2] (from (i))Candidates may use experimental data fromexperiments 2 or 3 to calculate the rate constantCIMk 2.04 10–2 0.163 OR 0.1632 dm3 mol–1 s–1 0.250 0.500ENQuestion17 (a) (i)June 20XXDO NOT ALLOW 0.161SPE 0.163 3 10–3 2 10–3 9.78 10–7 (mol dm–3 s–1) 10ALLOW ECF from (i)Note use of 0.1632 from (i) gives 9.79(2) 10–7

H432/01AnswerJune 20XXMarksGuidance2Boltzmann distribution – must start at origin andmust not end up at 0 on y-axis i.e. must nottouch x-axis at high energyMaximum of curve to rightAND lower than maximum of lower temperaturecurveAND above lower temp line at higher energy asshown in diagramENCorrect curve for higher temperature CIMActivation energy shown on diagramANDgraph shows that at higher temperature (owtte)more molecules have energy above activation energyOR more molecules have enough energy to react TotalSPEQuestion(b)Mark Scheme117link to graph required for mark

H432/01Answer H calculation from experimentJune 20XXMarks7Guidanceq 100 4.18 20.5 OR 8569 J OR 8.569 kJ Amount of butan-1-ol 0.259 3.5 10–3 mol 74–1 H 2448 kJ mol ENALLOW Calculator value for H 2448.285714 correctly rounded to three ormore significant figures S calculationCIM S Sproducts – Sreactants S (4 214) (5 70) – [(228) (6 205)]OR S 1206 – 1458 S –252 J K–1 mol–1 OR 0.252 kJ K–1 mol–1 G calculation G H T SSPEQuestion18Mark Scheme G –2448 – (298 –0.252) Mark for use of correct expression with S inkJ K 1 mol 1 G –2373 (kJ mol–1) ALLOW three or more sig figs for GTotal127

H432/01Mark SchemeQuestion19(a)AnswerMg(s) 2HCl(aq) MgCl2(aq) H2(g) MarksGuidance2State symbols are requiredEffervescence AND solid dissolves Lattice enthalpy of MgCl2 is more exothermic than CaCl2 because magnesium ion/Mg2 is smaller (than calciumions/Ca2 )OR Mg2 has a greater charge density 3ALLOW ‘charge density’ here onlyALLOW magnesium/Mg is smallerDO NOT ALLOW Mg2 has a smaller atomicradius(i)CIM therefore the attraction between Mg2 and Cl is greater(than between Ca2 and Cl–) FB3GEDFIVE correctFOUR correctTHREE correctSPE(c)ALLOW solid disappearsORA throughoutE

A Level Chemistry A H432/01 Periodic table, elements and physical chemistry Sample Question Paper Date – Morning/Afternoon Version 2.0 Time allowed: 2 hours 15 minutes You must have: the Data Sheet for Chemistry A You may use: a scientific or graphical calculator * 0 0 0 0