Cambridge A Level Chemistry 9701 — 2016 Oct/Nov Paper 3 · Variant 4

READ THESE INSTRUCTIONS FIRST Write your Centre number, candidate number and name on all the work you hand in. Give details of the practical session and laboratory where appropriate, in the boxes provided. 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 fluid. 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. Qualitative Analysis Notes are printed on pages 10 and 11. A copy of the Periodic Table is printed on page 12. 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 9701/34 Paper 3 Advanced Practical Skills 2 October/November 2016 2 hours Candidates answer on the Question Paper. Additional Materials: As listed in the Confidential Instructions Cambridge International Examinations Cambridge International Advanced Subsidiary and Advanced Level This document consists of 12 printed pages. [Turn over IB16 11_9701_34/4RP © UCLES 2016 *8553479171* Session Laboratory For Examiner’s Use 1 2 3 Total

2 9701/34/O/N/16 © UCLES 2016 1 You will find the relative atomic mass, Ar, of magnesium by measuring the volume of hydrogen produced when a known mass of metal reacts with an excess of acid. Mg(s) + 2HCl (aq) → MgCl 2(aq) + H2(g) FB 1 is 1.00 mol dm–3 hydrochloric acid, HCl. FB 2 is magnesium, Mg. (a) Method Read through the whole method before starting any practical work. • Fill the tub with water to a depth of about 5 cm. • Weigh the magnesium, FB 2, and note its mass below. If you are using a balance reading to 1 decimal place and the reading with the magnesium is zero, you should record this value. • Fill the burette to about the 20 cm3 mark with hydrochloric acid, FB 1. • Add distilled water to reach the 0 cm3 mark on the burette. • Bend the magnesium strip into a U-shape. • Place the magnesium in the burette so that it is above the liquid and friction holds it in position. Use a glass rod to push the magnesium about 2 cm into the burette. • Hold a piece of paper towel over the open end of the burette, invert the burette and immediately place it in the tub of water. Remove the paper towel and clamp the burette as shown in the diagram. • The liquid level should now be on the scale of the burette. If it is not, open the tap for a moment to allow the level to drop. burette magnesium ribbon clamp hydrochloric acid tub magnesium ribbon water burette • Record the initial reading on the burette. Remember that the scale is now upside down. • Leave the apparatus so that the acid from the burette diffuses around the magnesium and reacts. • You should start Question 2 or Question 3 while waiting for the reaction to complete. • When all the magnesium has reacted, note and record the final reading on the burette. • Calculate the volume of hydrogen produced. Results [3]

3 9701/34/O/N/16 © UCLES 2016 [Turn over (b) Calculations Show your working and appropriate significant figures in the final answer to each step of your calculations. (i) Calculate the number of moles of hydrogen produced. (Assume that 1 mole of gas occupies 24.0 dm3 under these conditions.) moles of H2 = … mol (ii) Use your answer to (i) and the mass of magnesium used to calculate the Ar of magnesium. (If you used a balance reading to 1 decimal place, you should assume that the mass of magnesium was 0.04 g correct to 2 decimal places.) Ar of Mg = … [2] (c) (i) Calculate the percentage error in the mass and volume readings in this experiment. (ii) Suggest a change that could be made to reduce the greater error calculated in (i). … … [3] (d) What would be the effect on the value of the Ar of magnesium calculated if the temperature of the room was much lower than that for your experiment? Explain your answer. … … … [2] [Total: 10]

4 9701/34/O/N/16 © UCLES 2016 2 In Question 1 you calculated the relative atomic mass, Ar, of magnesium by measuring the volume of hydrogen produced. The relative atomic mass can also be determined by investigating how much of the hydrochloric acid reacted with the magnesium. The experiment described in Question 1 was repeated, this time using 0.21 g of magnesium ribbon and 30.0 cm3 of 1.00 mol dm–3 hydrochloric acid. All the solution left in the burette and tub was kept and water added to make the total volume 250 cm3. This solution was labelled FB 3. You will titrate FB 3 using a known concentration of aqueous sodium carbonate to determine how much hydrochloric acid was left over after the reaction with magnesium. Na2CO3(aq) + 2HCl (aq) → 2NaCl (aq) + H2O(l) + CO2(g) FB 3 is the solution of hydrochloric acid described above. FB 4 is aqueous sodium carbonate containing 2.64 g dm–3 Na2CO3. bromophenol blue indicator (a) Method • Fill the burette with FB 3. • Pipette 25.0 cm3 of FB 4 into a conical flask. • Add about 10 drops of bromophenol blue indicator. • Perform a rough titration and record your burette readings in the space below. The rough titre is … cm3 • Carry out as many accurate titrations as you consider necessary to obtain consistent results. • Record, in a suitable form below, all of your burette readings and the volume of FB 3 added in each accurate titration. • Make certain any recorded results show the precision of your practical work. [7] I II III IV V VI VII

5 9701/34/O/N/16 © UCLES 2016 [Turn over (b) From your accurate titration results, obtain a suitable value for the volume of FB 3 to be used in your calculations. Show clearly how you obtained this value. 25.0 cm3 of FB 4 required … cm3 of FB 3. [1] (c) Calculations Show your working and appropriate significant figures in the final answer to each step of your calculations. (i) Use the information on page 4 and the Periodic Table on page 12 to calculate the number of moles of sodium carbonate in the 25.0 cm3 of FB 4 used in each titration. moles of Na2CO3 = … mol (ii) Use your answer to (i) to calculate the number of moles of hydrochloric acid present in the volume of FB 3 recorded in (b). Na2CO3(aq) + 2HCl (aq) → 2NaCl (aq) + H2O(l) + CO2(g) moles of HCl present = … mol (iii) Use your answer to (ii) to calculate the number of moles of hydrochloric acid present in 250 cm3 of FB 3. moles of HCl present in 250 cm3 = … mol

6 9701/34/O/N/16 © UCLES 2016 (iv) Use the information on page 4 to calculate the number of moles of hydrochloric acid added to the magnesium. moles of HCl added = … mol (v) Calculate the number of moles of hydrochloric acid that reacted with the magnesium. moles of HCl that reacted with the magnesium = … mol (vi) Use your answer to (v) and the mass of magnesium used to calculate the relative atomic mass, Ar, of magnesium. Mg(s) + 2HCl (aq) → MgCl 2(aq) + H2(g) Ar of Mg = … [5] (d) A solution of sodium hydroxide was prepared at the same concentration, in mol dm–3, as FB 4. A student repeated the titration but replaced FB 4 with this solution of sodium hydroxide. (i) Explain the effect that replacing FB 4 with this solution of sodium hydroxide would have on the volume of acid, FB 3, needed for the titration. … … (ii) If the sodium hydroxide had been stored for a long time it would not be suitable for use to find the concentration of the acid. Suggest why storage for a long time would make the sodium hydroxide unsuitable. … … [2] [Total: 15]

7 9701/34/O/N/16 © UCLES 2016 [Turn over 3 Qualitative Analysis At each stage of any test you are to record details of the following. ● colour changes seen ● the formation of any precipitate ● the solubility of such precipitates in an excess of the reagent added Where gases are released they should be identified by a test, described in the appropriate place in your observations. You should indicate clearly at what stage in a test a change occurs. No additional tests for ions present should be attempted. If any solution is warmed, a boiling tube MUST be used. Rinse and reuse test-tubes and boiling tubes where possible. Where reagents are selected for use in a test, the name or correct formula of the element or compound must be given. (a) (i) Half fill the 250 cm3 beaker with water. Heat the water to about 80 °C and then turn off the Bunsen burner. This is the hot water bath needed in the following tests. To a 3–4 cm depth of aqueous silver nitrate in a test-tube, add a few drops of aqueous sodium hydroxide to give a grey / brown precipitate. Then add aqueous ammonia dropwise until the precipitate just disappears. This solution is Tollens’ reagent and is needed in a following test.

8 9701/34/O/N/16 © UCLES 2016 FB 5, FB 6 and FB 7 are each known to be one of ethanol, propanal and propanone. Carry out the following tests and complete the table. test observations FB 5 FB 6 FB 7 To a 1 cm depth in a test-tube, add a few drops of acidified potassium manganate(VII) and place in the hot water bath. To a 0.5 cm depth in a test-tube, add a 1 cm depth of aqueous potassium iodide and a 1 cm depth of sodium chlorate(I). (This gives the same result as adding iodine and alkali.) To a few drops in a test-tube, add a 1 cm depth of Tollens’ reagent and place in the hot water bath. Leave for several minutes. (ii) Use these observations to identify the unknown compounds. FB 5 is … FB 6 is … FB 7 is … (iii) Choose another reagent that would give a similar result for propanal and propanone but a different result for ethanol. Do not carry out this test. reagent … result for propanal and propanone … result for ethanol … (iv) Choose another reagent that would give a similar result for ethanol and propanone but a different result for propanal. Do not carry out this test. reagent … result for ethanol and propanone … result for propanal … [8]

9 9701/34/O/N/16 © UCLES 2016 [Turn over (b) FB 8 contains one cation and one anion from those listed on pages 10 and 11. You are provided with solid FB 8 and an aqueous solution of FB 8. (i) To a 1 cm depth of aqueous FB 8 in a test-tube add a 1 cm depth of aqueous sodium hydroxide. Keep the test-tube and contents for test (ii). observation … (ii) Transfer the contents of the test-tube from test (i) into a boiling tube and heat gently and carefully. Allow to cool and keep the boiling tube and contents for test (iii). observation … (iii) Transfer a 1 cm depth of the mixture from test (ii) into a boiling tube and add a 2 cm depth of dilute hydrochloric acid. Heat gently and carefully. observation … Allow to cool and keep the boiling tube and contents for test (iv). (iv) To the boiling tube from test (iii) add a piece of aluminium foil. Leave the boiling tube to stand. observation … … (v) Place a small spatula measure of solid FB 8 in a hard-glass test-tube and heat it gently at first and then more strongly. Identify two gases, other than water vapour, that are produced and give your evidence. identity … evidence … identity … evidence … (vi) From your observations in (i) to (v), write the formula of FB 8. … (vii) Write the ionic equation for the reaction that is occurring in test (i). Include state symbols. … [7] [Total: 15]

10 9701/34/O/N/16 © UCLES 2016 Qualitative Analysis Notes Key: [ppt. = precipitate] 1 Reactions of aqueous cations ion reaction with NaOH(aq) NH3(aq) aluminium, Al 3+(aq) white ppt. soluble in excess white ppt. insoluble in excess ammonium, NH4 +(aq) no ppt. ammonia produced on heating – barium, Ba2+(aq) no ppt. (if reagents are pure) no ppt. calcium, Ca2+(aq) white ppt. with high [Ca2+(aq)] no ppt. chromium(III), Cr3+(aq) grey-green ppt. soluble in excess grey-green ppt. insoluble in excess copper(II), Cu2+(aq) pale blue ppt. insoluble in excess blue ppt. soluble in excess giving dark blue solution iron(II), Fe2+(aq) green ppt. turning brown on contact with air insoluble in excess green ppt. turning brown on contact with air insoluble in excess iron(III), Fe3+(aq) red-brown ppt. insoluble in excess red-brown ppt. insoluble in excess magnesium, Mg2+(aq) white ppt. insoluble in excess white ppt. insoluble in excess manganese(II), Mn2+(aq) off-white ppt. rapidly turning brown on contact with air insoluble in excess off-white ppt. rapidly turning brown on contact with air insoluble in excess zinc, Zn2+(aq) white ppt. soluble in excess white ppt. soluble in excess

11 9701/34/O/N/16 © UCLES 2016 2 Reactions of anions ion reaction carbonate, CO3 2– CO2 liberated by dilute acids chloride, Cl –(aq) gives white ppt. with Ag+(aq) (soluble in NH3(aq)) bromide, Br –(aq) gives cream ppt. with Ag+(aq) (partially soluble in NH3(aq)) iodide, I –(aq) gives yellow ppt. with Ag+(aq) (insoluble in NH3(aq)) nitrate, NO3 –(aq) NH3 liberated on heating with OH–(aq) and Al foil nitrite, NO2 –(aq) NH3 liberated on heating with OH–(aq) and Al foil; NO liberated by dilute acids (colourless NO → (pale) brown NO2 in air) sulfate, SO4 2–(aq) gives white ppt. with Ba2+(aq) (insoluble in excess dilute strong acids) sulfite, SO3 2–(aq) gives white ppt. with Ba2+(aq) (soluble in excess dilute strong acids) 3 Tests for gases gas test and test result ammonia, NH3 turns damp red litmus paper blue carbon dioxide, CO2 gives a white ppt. with limewater (ppt. dissolves with excess CO2) chlorine, Cl 2 bleaches damp litmus paper hydrogen, H2 “pops” with a lighted splint oxygen, O2 relights a glowing splint

12 9701/34/O/N/16 © UCLES 2016 To avoid the issue of disclosure of answer-related information to candidates, all copyright acknowledgements are reproduced online in the Cambridge International Examinations Copyright Acknowledgements Booklet. This is produced for each series of examinations and is freely available to download at www.cie.org.uk after the live examination series. Group The Periodic Table of Elements 1 H hydrogen 1.0 2 He helium 4.0 1 2 13 14 15 16 17 18 3 4 5 6 7 8 9 10 11 12 3 Li lithium 6.9 4 Be beryllium 9.0 atomic number atomic symbol Key name relative atomic mass 11 Na sodium 23.0 12 Mg magnesium 24.3 19 K potassium 39.1 20 Ca calcium 40.1 37 Rb rubidium 85.5 38 Sr strontium 87.6 55 Cs caesium 132.9 56 Ba barium 137.3 87 Fr francium – 88 Ra radium – 5 B boron 10.8 13 Al aluminium 27.0 31 Ga gallium 69.7 49 In indium 114.8 81 Tl thallium 204.4 6 C carbon 12.0 14 Si silicon 28.1 32 Ge germanium 72.6 50 Sn tin 118.7 82 Pb lead 207.2 22 Ti titanium 47.9 40 Zr zirconium 91.2 72 Hf hafnium 178.5 104 Rf rutherfordium – 23 V vanadium 50.9 41 Nb niobium 92.9 73 Ta tantalum 180.9 105 Db dubnium – 24 Cr chromium 52.0 42 Mo molybdenum 95.9 74 W tungsten 183.8 106 Sg seaborgium – 25 Mn manganese 54.9 43 Tc technetium – 75 Re rhenium 186.2 107 Bh bohrium – 26 Fe iron 55.8 44 Ru ruthenium 101.1 76 Os osmium 190.2 108 Hs hassium – 27 Co cobalt 58.9 45 Rh rhodium 102.9 77 Ir iridium 192.2 109 Mt meitnerium – 28 Ni nickel 58.7 46 Pd palladium 106.4 78 Pt platinum 195.1 110 Ds darmstadtium – 29 Cu copper 63.5 47 Ag silver 107.9 79 Au gold 197.0 111 Rg roentgenium – 30 Zn zinc 65.4 48 Cd cadmium 112.4 80 Hg mercury 200.6 112 Cn copernicium – 114 Fl flerovium – 116 Lv livermorium – 7 N nitrogen 14.0 15 P phosphorus 31.0 33 As arsenic 74.9 51 Sb antimony 121.8 83 Bi bismuth 209.0 8 O oxygen 16.0 16 S sulfur 32.1 34 Se selenium 79.0 52 Te tellurium 127.6 84 Po polonium – 9 F fluorine 19.0 17 Cl chlorine 35.5 35 Br bromine 79.9 53 I iodine 126.9 85 At astatine – 10 Ne neon 20.2 18 Ar argon 39.9 36 Kr krypton 83.8 54 Xe xenon 131.3 86 Rn radon – 21 Sc scandium 45.0 39 Y yttrium 88.9 57–71 lanthanoids 89–103 actinoids 57 La lanthanum 138.9 89 Ac lanthanoids actinoids actinium – 58 Ce cerium 140.1 90 Th thorium 232.0 59 Pr praseodymium 140.9 91 Pa protactinium 231.0 60 Nd neodymium 144.4 92 U uranium 238.0 61 Pm promethium – 93 Np neptunium – 62 Sm samarium 150.4 94 Pu plutonium – 63 Eu europium 152.0 95 Am americium – 64 Gd gadolinium 157.3 96 Cm curium – 65 Tb terbium 158.9 97 Bk berkelium – 66 Dy dysprosium 162.5 98 Cf californium – 67 Ho holmium 164.9 99 Es einsteinium – 68 Er erbium 167.3 100 Fm fermium – 69 Tm thulium 168.9 101 Md mendelevium – 70 Yb ytterbium 173.1 102 No nobelium – 71 Lu lutetium 175.0 103 Lr lawrencium –

® IGCSE is the registered trademark of Cambridge International Examinations. This document consists of 10 printed pages. © UCLES 2016 [Turn over Cambridge International Examinations Cambridge International Advanced Subsidiary and Advanced Level CHEMISTRY 9701/34 Paper 3 Advanced Practical Skills 2 October/November 2016 MARK SCHEME Maximum Mark: 40 Published This mark scheme is published as an aid to teachers and candidates, to indicate the requirements of the examination. It shows the basis on which Examiners were instructed to award marks. It does not indicate the details of the discussions that took place at an Examiners’ meeting before marking began, which would have considered the acceptability of alternative answers. Mark schemes should be read in conjunction with the question paper and the Principal Examiner Report for Teachers. Cambridge will not enter into discussions about these mark schemes. Cambridge is publishing the mark schemes for the October/November 2016 series for most Cambridge IGCSE®, Cambridge International A and AS Level components and some Cambridge O Level components.

Page 2 Mark Scheme Syllabus Paper Cambridge International AS/A Level – October/November 2016 9701 34 © UCLES 2016 Question Answer Marks 1(a) I Mass of magnesium recorded with /g or (g) and initial and final burette readings and volume of hydrogen with unambiguous headings and correct unit. 1 Examiner to calculate 10% and 20% of Supervisor’s volume and round this to 1 dp. Candidate’s volume compared with Supervisor’s volume. Award II if within 20% Award II and III if within 10% 1 1 3 1(b)(i) Correct calculation moles H2 = volume collected 24000 to 2 – 4 sf Volume of gas must be correctly calculated. 1 1(b)(ii) Correctly uses Ar = mass used (i) to 2 – 4 sf 1 2

Page 3 Mark Scheme Syllabus Paper Cambridge International AS/A Level – October/November 2016 9701 34 © UCLES 2016 Question Answer Marks 1(c)(i) Correct expression Error in mass = 0.1 or 0.01 or 0.001 100 mass of Mg ∗ × (depending on dp of balance) 1 Correct expression Error in volume = 0.1 100 volume of gas in ∗ × (a) 1 1(c)(ii) Use a larger mass of magnesium (for either)/use a balance that reads to more dp (mass error was larger)/use a burette more precisely calibrated/smaller graduations (volume error was larger) 1 3

Page 4 Mark Scheme Syllabus Paper Cambridge International AS/A Level – October/November 2016 9701 34 © UCLES 2016 Question Answer Marks 1(d) Volume (gas) measured/or moles/amount gas/H2 would have been less Ar greater but must follow from smaller moles of H2/Mg or Use correct molar volume for new room temperature Ar unchanged (but must follow from Vm smaller) 1 1 or 1 1 2 Total: 10 Question Answer Marks 2(a) I Initial and final burette readings and volume added recorded for rough titre and initial and final reading for two (or more) accurate titrations 1 II Initial and final burette readings and volume of FB 3 added recorded for each accurate titration. Headings and units correct for accurate titrations. Heading: initial/final (burette) reading/volume or reading/volume at start/finish and volume/FB 3 added/used or titre (not difference/amount/total unless total as an extra with volume used/ titre,) and Units: (cm3) or/ cm3 or in cm3 or cm3 by every entry 1

Page 5 Mark Scheme Syllabus Paper Cambridge International AS/A Level – October/November 2016 9701 34 © UCLES 2016 Question Answer Marks III All accurate burette readings recorded to the nearest 0.05 cm3 Do not award this mark if: 50(.00) is used as an initial burette reading; more than one final burette reading is 50(.00) any burette reading is > 50(.00) 1 IV Final uncorrected titre is within 0.10 cm3 of any previous uncorrected accurate titre. 1 Examiner rounds any accurate burette readings to the nearest 0.05 cm3, checks subtractions and then selects the ‘best’ accurate titres using the hierarchy: identical titres; titres within 0.05 cm3; titres within 0.1 cm3; etc., to calculate mean correct to 0.01 cm3. Examiner compares candidate’s titre value with that of the Supervisor. V, VI and VII Award V, VI and VII for δ ≤ 0.20 cm3 Award V and VI for 0.20 cm3 < δ ≤ 0.30 cm3 Award V for 0.30 cm3 < δ ≤ 0.50 cm3 1 1 1 7 2(b) Calculation of mean Check mean titre is correctly calculated from clearly selected values (ticks or working) • Candidate must average two (or more) titres where the total spread is ≤ 0.20 cm3. • Working must be shown or ticks must be put next to the two (or more) accurate readings selected. • The mean should normally be quoted to 2 dp rounded to the nearest 0.01. [e.g. 26.667 must be rounded to 26.67] Two special cases where the mean may not be to 2 dp: allow mean to 3 dp only for 0.025 or 0.075 e.g. 26.325; allow mean to 1 dp if all accurate burette readings were given to 1 dp (ignoring initial given 1

Page 6 Mark Scheme Syllabus Paper Cambridge International AS/A Level – October/November 2016 9701 34 © UCLES 2016 Question Answer Marks as 0) and the mean is exactly correct. [e.g. 26.0 and 26.2 = 26.1 is correct but 26.0 and 26.1 = 26.1 is incorrect.] Do not award this mark if: • the rough titre was used to calculate the mean; • the candidate carried out only 1 accurate titration; • burette readings were incorrectly subtracted to obtain any of the accurate titre values; • all burette readings (resulting in titre values used in the calculation of the mean) are integers. Note: the candidate’s mean will sometimes be marked as correct even if it is different from the mean calculated by the examiner for the purpose of assessing accuracy. 1 2(c)(i) Correctly calculates 4 2.64 6.23 / 6.225 / 6.226 10 106 40 − = × × 1 2(c)(ii) and 2(c)(iii) Correctly uses (i) × 2 and 250 × (ii) (b) 1 2(c)(iv) Correctly calculates Moles 30 1.00 HC = = 0.03(00) 1000 × l 1

Page 7 Mark Scheme Syllabus Paper Cambridge International AS/A Level – October/November 2016 9701 34 © UCLES 2016 Question Answer Marks 2(c)(v) and 2(c)(vi) Correctly uses (iv) – (iii) and 0.21 2 × (v) 1 Answers to 3 or 4 sf (minimum 4 answers attempted, allow 2 sf in (vi)) 1 5 2(d)(i) Half the volume needed since 1:1 ratio/1 mole NaOH in equation 1 2(d)(ii) (Impure) since absorbed/reacted with CO2 or water vapour/water from the air 1 2 Total 15

Page 8 Mark Scheme Syllabus Paper Cambridge International AS/A Level – October/November 2016 9701 34 © UCLES 2016 Question Answer Marks FB 5 is CH3COCH3 FB 6 is C2H5OH FB 7 is C2H5CHO FB 8 is Cu(NO3)2 3(a)(i) FB 5 FB 6 FB 7 Acidified MnO4 − no reaction Purple to colourless (solution)/(solution) turns colourless KI + ClO− (Pale) yellow/cream solid/ppt no reaction Tollens’ no reaction Silver/black/ (dark) grey solid/ ppt/silver mirror 1 1 1 3(a)(ii) FB 5 is propanone, FB 6 is ethanol, FB 7 is propanal 1

Page 9 Mark Scheme Syllabus Paper Cambridge International AS/A Level – October/November 2016 9701 34 © UCLES 2016 Question Answer Marks 3(a)(iii) Reagent: 2,4–dinitrophenylhydrazine/2,4–DNP(H)/Brady’s reagent Result: propanone and propanal: orange/yellow and solid/ppt (not red) ethanol: no reaction/stays yellow (allow remains colourless) or Reagent: SOCl2/PCl3/PCl5 Result: propanone and propanal: no visible reaction/no misty fumes ethanol: steamy/misty fumes (allow white fumes) or Reagent: ethanoic acid + conc H2SO4 (and warm) Result: propanone and propanal: no reaction/ no sweet smell ethanol: sweet/ fruity smell or Reagent: Na Result: propanone and propanal: no reaction/ no bubbles ethanol: effervescence/ bubbling/ fizzing 1 1 or 1 1 or 1 1 or 1 1 3(a)(iv) Reagent: Fehling’s/Benedict’s/Sandell’s Result: ethanol and propanone: no reaction/stays/turns blue propanal: orange/red/brick-red solid/ ppt 1 1 8 3(b)(i) (Pale) blue ppt (not dark blue) 1 3(b)(ii) Black solid 1 3(b)(iii) Blue/green solution 1

Page 10 Mark Scheme Syllabus Paper Cambridge International AS/A Level – October/November 2016 9701 34 © UCLES 2016 Question Answer Marks 3(b)(iv) Any two of • effervescence/bubbling/fizzing • solid goes pink/brown (allow red-brown) • blue/colour of solution fades (owtte) 1 3(b)(v) Oxygen relights glowing splint or nitrogen dioxide is brown 1 3(b)(vi) Cu(NO3)2 1 3(b)(vii) Cu2+(aq) + 2OH−(aq) → Cu(OH)2(s) 1 7 Total: 15