Cambridge IGCSE Physical Science 0652 — 2011 Oct/Nov Paper 5 · Variant 1

This document consists of 8 printed pages and 4 blank pages. IB11 11_0652_51/RP © UCLES 2011 [Turn over *0017405524* For Examiner's Use 1 2 Total UNIVERSITY OF CAMBRIDGE INTERNATIONAL EXAMINATIONS International General Certificate of Secondary Education PHYSICAL SCIENCE 0652/51 Paper 5 Practical Test October/November 2011 1 hour 30 minutes Candidates answer on the Question Paper. Additional Materials: As listed in Instructions to Supervisors 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 a pencil for any diagrams, graphs or rough working. Do not use staples, paper clips, highlighters, glue or correction fluid. DO NOT WRITE IN ANY BARCODES. Answer all questions. Chemistry practical notes for this paper are 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.

2 © UCLES 2011 0652/51/O/N/11 For Examiner's Use 1 You are going to investigate the thermal decomposition of three metal carbonates, comparing the thermal decomposition of each carbonate with the reactivity of its metal with acid. Finally, you will identify an unknown metal. (a) (i) Place compound A, which is a metal carbonate, in a clean hard glass test-tube. Place about 3 cm3 of limewater in a second test-tube. Connect the bung of the delivery tube to the test-tube containing A and place the delivery tube into the limewater as shown in Fig. 1.1. limewater metal carbonate A heat Fig. 1.1 (ii) Heat the tube containing compound A with a hot flame, starting the clock as you do so. When the limewater becomes milky, stop the clock and immediately remove the delivery tube from the limewater. Record the time taken, in seconds, for the limewater to become milky, as well as any colour change to the carbonate, in Table 1.1. Table 1.1 compound name and formula time / s colour change A zinc carbonate, ZnCO3 B magnesium carbonate, MgCO3 C unknown metal carbonate, XCO3 [1] (iii) Repeat (a)(i) and (a)(ii) with the compounds B and C, using fresh limewater each time. Record the results in Table 1.1. [2] Keep the test-tube containing the result of heating compound C for part (c).

3 © UCLES 2011 0652/51/O/N/11 [Turn over For Examiner's Use (iv) List the metal carbonates in order of their speed of turning limewater milky (speed of thermal decomposition). 1 (fastest) 2 3 (slowest) [1] (v) Name the gas produced by the thermal decomposition of a metal carbonate. name [1] (b) (i) Place a piece of zinc into a clean test-tube. Place a piece of magnesium into a second test-tube and a piece of unknown metal X into a third test-tube. Add about 3 cm3 of dilute sulfuric acid to each test-tube. Record your observations in Table 1.2. Table 1.2 metal observations zinc magnesium unknown metal X [3] (ii) List the metals tested in (b)(i) in order of reactivity. 1 (most reactive) 2 3 (least reactive) [1] (iii) Compare your answers to (a)(iv) and (b)(ii). Can the order of reactivity of metals be used to predict the order of speed of thermal decomposition of metal carbonates? Explain your answer. [1]

4 © UCLES 2011 0652/51/O/N/11 For Examiner's Use (c) Empty the contents of the test-tube in which compound C was heated into a beaker. Add about 10 cm3 of dilute sulfuric acid and stir well. Filter the resulting mixture into two clean test-tubes. Keep the filtrate for parts (c)(i) and (c)(ii). (i) Carefully add dilute sodium hydroxide to the filtrate in one of the test-tubes until there is no further change. Record your observation. [1] (ii) To the other test-tube containing the filtrate, add a piece of zinc. Record your observations. [2] (iii) Identify metal X and state two pieces of evidence to support this. metal X is evidence 1 evidence 2 [2]

5 © UCLES 2011 0652/51/O/N/11 [Turn over BLANK PAGE Please turn over for Question 2.

6 © UCLES 2011 0652/51/O/N/11 For Examiner's Use 2 You are going to investigate how the angle of swing, θ, affects the time period for one oscillation, T, of a simple pendulum. You will also use your results to calculate the acceleration due to gravity, g. (a) Set up your pendulum as in Fig. 2.1, using the apparatus provided, such that the length, l, is 30 cm. Clamp the cork and secure the protractor card to the cork with the short pin. Attach the protractor to the card as shown, using the long pin. Suspend the pendulum from the long pin. short pin long pin protractor card stand pendulum length, l Fig. 2.1 Displace the pendulum by θ = 10° as shown in Fig. 2.2. 0 180 170 160 150 140 130 120 110 100 80 70 60 50 40 30 20 10 0 10 20 30 40 50 60 70 80 100 110 120 130 140 150 160 170 180 90 θ Fig. 2.2 (i) Release the pendulum and start the clock at the same time. Stop the clock when the pendulum has completed ten oscillations. (One oscillation is swinging away from and back to the release point). Record the time in Table 2.1 to 0.1 second.

7 © UCLES 2011 0652/51/O/N/11 [Turn over For Examiner's Use (ii) Repeat the experiment for θ = 10° a further four times and record the results in Table 2.1. (iii) Now carry out the experiment five times each for angles of swing θ = 20° and θ = 30° recording all results in Table 2.1. Table 2.1 time for 10 oscillations / s θ = 10° θ = 20° θ = 30° 1 2 3 4 5 average for 10 oscillations / s period, T / s [5] (b) (i) Calculate the average time for 10 oscillations for each angle of swing, θ. Record your averages in Table 2.1. [1] (ii) Calculate the period, T (the time for one oscillation), from the average for 10 oscillations for each angle of swing, θ. Record values of T in Table 2.1. [1] (iii) Describe the relationship between the period, T, and the angle of swing, θ. [1]

8 © UCLES 2011 0652/51/O/N/11 For Examiner's Use (iv) Explain how you can tell that the period, T, is not proportional to the angle of swing, θ. [1] (c) Use the period T for θ = 10° in Table 2.1 to calculate the acceleration due to gravity, g, using the formula below. You must include units in your answer. (the length of the pendulum, l, must be in metres). T 2 39.5 x l g = g = units [3] (d) (i) Explain why you timed 10 oscillations in your experiments rather than timing just one oscillation to obtain the period, T, directly. [1] (ii) Suggest one possible source of error in this experiment to find a value for g. [1] (iii) For the source of error you have chosen in (d)(ii), describe how this error could be reduced. [1]

9 © UCLES 2011 0652/51/O/N/11 BLANK PAGE

10 © UCLES 2011 0652/51/O/N/11 BLANK PAGE

11 © UCLES 2011 0652/51/O/N/11 BLANK PAGE

12 Permission to reproduce items where third-party owned material protected by copyright is included has been sought and cleared where possible. Every reasonable 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. University of 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. © UCLES 2011 0652/51/O/N/11 CHEMISTRY PRACTICAL NOTES Test for anions anion test test result carbonate (CO3 2-) add dilute acid effervescence, carbon dioxide produced chloride (Cl -) [in solution] acidify with dilute nitric acid, then add aqueous silver nitrate white ppt. nitrate (NO3 -) [in solution] add aqueous sodium hydroxide then aluminium foil; warm carefully ammonia produced sulfate (SO4 2-) [in solution] acidify then add aqueous barium chloride or aqueous barium nitrate white ppt. Test for aqueous cations cation effect of aqueous sodium hydroxide effect of aqueous ammonia ammonium (NH4 +) ammonia produced on warming - copper(II) (Cu2+) light blue ppt., insoluble in excess light blue ppt., soluble in excess giving a dark blue solution iron(II) (Fe2+) green ppt., insoluble in excess green ppt., insoluble in excess iron(III) (Fe3+) red-brown ppt., insoluble in excess red-brown ppt., insoluble in excess zinc (Zn2+) white ppt., soluble in excess giving a colourless solution white ppt., soluble in excess giving a colourless solution Test for gases gas test and test results ammonia (NH3) turns damp red litmus paper blue carbon dioxide (CO2) turns limewater milky chlorine (Cl2) bleaches damp litmus paper hydrogen (H2) “pops” with a lighted splint oxygen (O2) relights a glowing splint

UNIVERSITY OF CAMBRIDGE INTERNATIONAL EXAMINATIONS International General Certificate of Secondary Education MARK SCHEME for the October/November 2011 question paper for the guidance of teachers 0652 PHYSICAL SCIENCE 0652/51 Paper 5 (Practical Test), maximum raw mark 30 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 must be read in conjunction with the question papers and the report on the examination. • Cambridge will not enter into discussions or correspondence in connection with these mark schemes. Cambridge is publishing the mark schemes for the October/November 2011 question papers for most IGCSE, GCE Advanced Level and Advanced Subsidiary Level syllabuses and some Ordinary Level syllabuses.

Page 2 Mark Scheme: Teachers’ version Syllabus Paper IGCSE – October/November 2011 0652 51 © University of Cambridge International Examinations 2011 1 (a) compound changes name and formula time / s colour A zinc carbonate, ZnCO3 e.g. 31 yellow (when hot) B magnesium carbonate, MgCO3 e.g. 21 (remains) white C unknown metal carbonate, XCO3 e.g. 28 (green to) black (ii) A: a value of time (in seconds) AND yellow / yellow when hot (ignore references to the limewater) ; [1] (iii) B: a value of time AND white / no change / same (ignore references to the limewater) ; C: a value of time AND black (ignore references to the limewater) ; [2] (iv) 1 (fastest) = one with shortest time 2 = one with intermediate time 3 (slowest) = one with longest time ; [1] (note: this must be consistent with candidates’ results) (v) carbon dioxide / CO2 ; [1] (b) (i) metal observations zinc bubbles ; magnesium fast bubbles / gets hot / metal disappears ; X no reaction ; [3] (ii) 1 (most reactive) = magnesium (B) ; 2 = zinc (A) ; 3 (least reactive) = X (C) ; [1] (this response must relate to the results in (b) (i). If there are no results in (b) (i) then the answer must be as above.) (iii) yes (if answer to (a) (iv) is Mg, Zn, X (B, A, C) or X, Zn, Mg (C, A, B)) AND order is same / reverse order compared with order in (b) (i) ; OR no (if answer to (a) (iv) is not Mg, Zn, X (B, A, C) or X, Zn, Mg (C, A, B)) AND not in same / reverse order compared with order in (b) (i) ; [max 1] (c) (i) blue ppt. / grey-blue ppt. / green-blue ppt. ; [1] (ii) brown / black solid OR zinc turns brown / black ; bubbles / effervescence / colourless solution / solution less blue / gets hot ; [2]

Page 3 Mark Scheme: Teachers’ version Syllabus Paper IGCSE – October/November 2011 0652 51 © University of Cambridge International Examinations 2011 (iii) X = copper / Cu ; (note: do not allow copper(II) / Cu2+) [1] evidence 1 and evidence 2: any two for one mark blue ppt. with NaOH (in (c) (ii)) and / or blue solution in (c) ; copper carbonate is green ; copper oxide is black ; brown solid (in (c) (ii)) ; displacement by zinc gives brown solid ; X is brown ; X does not react with acid ; [max 1] [Total: 15] 2 (a) any five readings (allow full reading from clock) ; any complete column of readings (allow full reading from clock) ; all 15 readings entered (allow full reading from clock) ; average of readings increasing from θ = 10° to 30° ; all readings recorded to 0.1 s ; [5] (b) (i) all 3 averages correctly calculated to at least 1 decimal place ; [1] (ii) all 3 T values calculated correctly to at least 1 decimal place (average ÷ 10) ; [1] (iii) T increases as angle of swing increases OR a relationship consistent with results [max 1] (iv) when θ is doubled T is not doubled / T not changing by same factor / other correct statement consistent with candidates’ results ; [1] (c) use of l = 0.30 m ; correct calculation of g to at least 1 decimal place using correct T from table which must be squared (allow ecf for l in cm in which case answer is 100 times greater) ; units of m s–2 or m / s2 ; [3] (d) (i) any errors are reduced (divided by ten) / reduced effect of timing error ; [1] (ii) simultaneous release of pendulum and starting stop clock ; judging completion of oscillations ; timing of 10 oscillations / human reaction time (do not allow just ‘timing’) ; measuring length of pendulum to centre of bob ; measuring angle accurately / protractor not positioned correctly ; [max 1] (iii) light gate or auto release timer ; more oscillations ; measure bob with callipers and measure cotton accordingly ; set up protractor with a plumb line to check alignment ; [max 1] [Total: 15]