Cambridge IGCSE Sciences - Co-ordinated (Double) 0654 — 2010 Oct/Nov Paper 3 · Variant 3

This document consists of 24 printed pages and 4 blank pages. IB10 11_0654_33/3RP © UCLES 2010 [Turn over *7898780349* For Examiner's Use 1 2 3 4 5 6 7 8 9 10 Total UNIVERSITY OF CAMBRIDGE INTERNATIONAL EXAMINATIONS International General Certificate of Secondary Education CO-ORDINATED SCIENCES 0654/33 Paper 3 (Extended) October/November 2010 2 hours Candidates answer on the Question Paper. No Additional Materials are required. 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 soft pencil for any diagrams, graphs, tables or rough working. Do not use staples, paper clips, highlighters, glue or correction fluid. DO NOT WRITE IN ANY BARCODES. Answer all questions. A copy of the Periodic Table is printed on page 28. 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. www.XtremePapers.com

2 © UCLES 2010 0654/33/O/N/10 For Examiner's Use 1 (a) In electrochemical cells (batteries), electrical energy is obtained from chemical reactions. Fig. 1.1 shows some uses of electrochemical cells. 6 5 4 3 2 1 12 11 10 9 8 7 + – watch torch (flashlight) car battery Fig. 1.1 (i) Small electrochemical cells, like those used in watches and torches (flashlights), stop working and have to be replaced fairly frequently. Explain what has happened inside the cells to cause them to stop working. [1] (ii) Explain why car batteries may never need to be replaced during the lifetime of the car. [1]

3 © UCLES 2010 0654/33/O/N/10 [Turn over For Examiner's Use (b) Electrical energy may be obtained from an electrochemical cell made by placing metal electrodes into a potato. Fig. 1.2 shows a diagram of such a cell. potato metal electrode metal electrode voltmeter 0 1.0 Fig. 1.2 A student investigated the use of different metals as electrodes. The metals he used are listed below in order of reactivity. magnesium (most reactive) zinc lead ↓ copper (least reactive) (i) Suggest why a potato can be used as part of an electrochemical cell. [1] (ii) State the pair of metals from the list that would produce the highest voltage when used as the electrodes. Explain your answer. [2]

4 © UCLES 2010 0654/33/O/N/10 For Examiner's Use (c) Some modern cars, known as hybrids, have two engines. One of these engines uses hydrocarbon fuel (gasoline) which is combusted (burned) to provide the energy required to move the car. The second engine is a powerful electric motor which uses energy provided by an electrochemical cell. When the car moves away from rest and continues to move slowly, the electric motor drives the car and the combustion engine is switched off. (i) Heptane, C7H16, is an alkane found in gasoline. Complete the balanced symbolic equation below for the combustion of heptane. C7H16 + → 7CO2 + 8H2O [2] (ii) Suggest why there could be an improvement to the environment, particularly in towns and cities, if hybrid cars replaced ordinary cars. [3]

5 © UCLES 2010 0654/33/O/N/10 [Turn over For Examiner's Use 2 (a) Fig. 2.1 is a photograph of a plant tissue seen through a light microscope. B A Fig. 2.1 (i) Name the structures labelled A and B. A B [2] (ii) Describe two ways in which the cells in Fig. 2.1 differ from animal cells. 1 2 [2]

6 © UCLES 2010 0654/33/O/N/10 For Examiner's Use (b) Fig. 2.2 shows apparatus that was used to investigate transpiration. The two pieces of apparatus were set up and left in the same conditions for 24 hours. The levels of water at the start and end of the 24 hours are shown on the diagram. 100 50 cm3 100 50 cm3 original level cover final level P Q Fig. 2.2 (i) Suggest why the level of water went down more in Q than in P. [3] (ii) Predict the results that would be obtained if apparatus Q was left in the same position for the next 24 hours, but at a higher temperature. Explain your prediction. [3]

7 © UCLES 2010 0654/33/O/N/10 [Turn over For Examiner's Use 3 (a) The isotope protactinium-234 undergoes radioactive decay by emitting beta radiation. Protactinium-234 has a half-life of 105 seconds. (i) Explain the meaning of the terms radioactive decay and half-life. radioactive decay half-life [2] (ii) 0.400 mg of protactinium-234 decays until 0.025 mg remain. Calculate how long this takes. Show your working. [2] (b) Apart from nuclear weapons and nuclear power, describe one practical use of radioactive isotopes. [2]

8 © UCLES 2010 0654/33/O/N/10 For Examiner's Use 4 (a) Fig. 4.1 shows the percentage of people living in Australia who have blood groups O, A, B and AB. 50 40 30 20 10 0 O A B AB blood group percentage of people Fig. 4.1 (i) Blood groups in humans show discontinuous variation. Explain what is meant by discontinuous variation. [2] (ii) Use the information in Fig. 4.1 to suggest whether a person’s blood group is caused by their genes, their environment, or both genes and environment. Explain your answer. [2]

9 © UCLES 2010 0654/33/O/N/10 [Turn over For Examiner's Use (b) (i) Give one example of continuous variation in humans. [1] (ii) On the axes below, sketch a graph to show continuous variation in the feature you have given in (b)(i). Label the axes on your graph. ` [3] (c) All species show variation in some of their characteristics. Explain why this variation is important in evolution. You may like to use an example to help your explanation. [4]

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11 © UCLES 2010 0654/33/O/N/10 [Turn over For Examiner's Use 5 (a) Fig. 5.1 shows a simple circuit containing two identical lamps. A2 A1 A3 V1 V2 12 V Fig. 5.1 Ammeter A1 reads 0.30 A. Write down the readings on ammeter A2 ammeter A3 voltmeter V1 voltmeter V2 [2]

12 © UCLES 2010 0654/33/O/N/10 For Examiner's Use (b) A student investigated the relationship between the potential difference across a lamp and the current in the lamp. Fig. 5.2 shows a graph of the results of this investigation. 0 1 2 3 4 5 6 1.2 1.0 0.8 0.6 0.4 0.2 0 potential difference / V current / A × × × × × × × Fig. 5.2 (i) Calculate the resistance of the lamp when the current was 0.6 A. State the formula that you use and show your working. formula used working [2]

13 © UCLES 2010 0654/33/O/N/10 [Turn over For Examiner's Use (ii) Explain why the lamp does not obey Ohm’s law. [2] (iii) On Fig. 5.2, sketch a line which could have been obtained if the lamp did obey Ohm’s law. [1] (c) Fig. 5.3 shows a soft iron ring. Two coils X and Y, each of 400 turns, are wound around the ring. Coil X is connected to a power supply and coil Y is connected to a 6 V lamp. power supply coil X coil Y Fig. 5.3 Describe and explain what happens to the lamp when the power supply is 6 V d.c., the power supply is 6 V a.c. [3]

14 © UCLES 2010 0654/33/O/N/10 For Examiner's Use 6 Table 6.1 shows some properties of five elements, P to T. The code letters are not the chemical symbols of the elements. Table 6.1 element code letter melting point / °C boiling point / °C conduction of electricity number of outer electrons in an atom P −89 −186 insulator 8 Q −39 357 conductor 2 R −7 58 insulator 7 S 181 1342 conductor 1 T 114 184 insulator 7 Answer the following questions, using only the code letters of the elements shown in Table 6.1. (a) (i) State and explain which element is very unreactive. element explanation [1] (ii) State and explain which element is a metal and a liquid at a room temperature of 20 °C. element explanation [2] (iii) Elements R and T are halogens. Use information from Table 6.1 to state and explain which of these elements has the greater proton number. element explanation [2]

15 © UCLES 2010 0654/33/O/N/10 [Turn over For Examiner's Use (b) Fig. 6.1 shows atoms of the two elements, R and S. Only the outer electron shells are shown. R × × × × × × × S × Fig. 6.1 Elements R and S react vigorously together to form an ionic compound. The compound that forms has a very high melting point. (i) Describe, in terms of electrons, how ionic bonds are formed between atoms of R and S. [2] (ii) Explain, in terms of structure and the forces between ions, why the compound containing R and S is a solid with a high melting point. [3]

16 © UCLES 2010 0654/33/O/N/10 For Examiner's Use (c) Suggest the process which is used to extract the element potassium from its compounds. Give a reason for your choice of process. [2]

17 © UCLES 2010 0654/33/O/N/10 [Turn over For Examiner's Use 7 Fig. 7.1 shows the driving force acting on a car of mass 1200 kg travelling at a constant speed of 18 m / s. driving force 1000 N Fig. 7.1 (a) Calculate the amount of work done by the driving force in one minute. Show your working. [2] (b) The car when travelling at 18 m / s is stopped using a braking force of 10 000 N. (i) Calculate the deceleration of the car. State the formula that you use and show your working. formula used working [2] (ii) Calculate the time needed for the car to stop. State the formula that you use and show your working. formula used working [2]

18 © UCLES 2010 0654/33/O/N/10 For Examiner's Use (c) Fig. 7.2 shows a car on a hydraulic lift in a garage. The total weight being lifted is 18 000 N. The lift uses four large pistons. Each large piston has an area of 0.03 m2. The smaller piston X has an area of 0.01 m2. hydraulic fluid piston X area 0.01 m2 piston area of each large piston 0.03 m2 Fig. 7.2 (i) Calculate the total area of the four large pistons. [1] (ii) Use the formula pressure = force / area to calculate the pressure in the hydraulic fluid used in the lift. Show your working. [1]

19 © UCLES 2010 0654/33/O/N/10 [Turn over For Examiner's Use (iii) This pressure is caused by piston X. Calculate the minimum force which piston X must exert to lift the car. Show your working. [1]

20 © UCLES 2010 0654/33/O/N/10 For Examiner's Use 8 Fig. 8.1 shows a section through the human thorax. Fig.8.1 (a) On the diagram, use a label line and the appropriate letter to indicate: A a muscle that contracts to bring about inspiration (breathing in) B an area where gas exchange takes place C a structure that rises during expiration (breathing out) [3] (b) Describe the pathway taken by blood as it passes from the heart to the lungs and back to the heart again. [3] (c) Describe how the blood transports oxygen. [2]

21 © UCLES 2010 0654/33/O/N/10 [Turn over For Examiner's Use (d) Describe how oxygen is supplied to a developing fetus in its mother’s uterus. [3]

22 © UCLES 2010 0654/33/O/N/10 For Examiner's Use 9 Nitrogen compounds in soil are taken up by growing crops. Fig. 9.1 shows two ways in which nitrogen compounds may be added to soil used for growing crops. fertiliser NPK nitrogen molecules in the air nitrogen compounds in the soil nitrogen fixation Fig. 9.1 (a) (i) State the meaning of the term nitrogen fixation and describe briefly one way in which this can occur. [3] (ii) Explain why nitrogen molecules taken directly from the air cannot be used by most growing crops. [1]

23 © UCLES 2010 0654/33/O/N/10 [Turn over For Examiner's Use (b) The nitrogen in NPK fertiliser exists in the form of compounds such as the salts ammonium nitrate, NH4NO3, and diammonium phosphate, (NH4)2HPO4. Diammonium phosphate may be obtained by reacting ammonia with phosphoric acid. The balanced symbolic equation for this reaction is 2NH3 + H3PO4 → (NH4)2HPO4 (i) State the number of moles of diammonium phosphate which are produced when 0.1 mol of ammonia react. [1] (ii) The relative formula mass of diammonium phosphate is 132. Calculate the mass of diammonium phosphate which is produced when 0.1 mol of ammonia reacts. Show your working. [2] (c) Plants produce glucose which provides energy during respiration. Excess glucose is stored in the plant in the form of starch. (i) Outline, in terms of molecules, what happens when glucose is changed into starch. [2] (ii) Glucose is soluble in water but starch is insoluble. Describe and explain the difference in appearance between a solution of glucose and the sol (colloid) which forms when starch is dispersed in water. [3]

24 © UCLES 2010 0654/33/O/N/10 For Examiner's Use 10 (a) An athlete of mass 70 kg is running at a speed of 10 m / s in a sprint race. Calculate the athlete’s kinetic energy. State the formula that you use and show your working. formula used working [3] (b) At the end of the race, evaporation helps to cool the athlete. (i) Use the idea of particles to explain how evaporation helps the athlete to cool down. [2] (ii) At the end of a long race, an athlete may be wrapped in a shiny foil blanket to prevent him cooling down too quickly. Explain how the shiny foil blanket helps to reduce energy losses. Use ideas about conduction, convection and radiation in your answer. [3]

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27 Copyright Acknowledgements: Question 2 Photograph Dr E Jones © UCLES 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 2010 0654/33/O/N/10 BLANK PAGE

28 © UCLES 2010 0654/33/O/N/10 Group 140 Ce Cerium 58 141 Pr Praseodymium 59 144 Nd Neodymium 60 Pm Promethium 61 150 Sm Samarium 62 152 Eu Europium 63 157 Gd Gadolinium 64 159 Tb Terbium 65 162 Dy Dysprosium 66 165 Ho Holmium 67 167 Er Erbium 68 169 Tm Thulium 69 173 Yb Ytterbium 70 175 Lu Lutetium 71 232 Th Thorium 90 Pa Protactinium 91 238 U Uranium 92 Np Neptunium 93 Pu Plutonium 94 Am Americium 95 Cm Curium 96 Bk Berkelium 97 Cf Californium 98 Es Einsteinium 99 Fm Fermium 100 Md Mendelevium 101 No Nobelium 102 Lr Lawrencium 103 1 H Hydrogen 1 7 Li Lithium 3 23 Na Sodium 11 24 Mg Magnesium 12 40 Ca Calcium 20 45 Sc Scandium 21 48 Ti Titanium 22 51 V Vanadium 23 52 Cr Chromium 24 55 Mn Manganese 25 56 Fe Iron 26 59 Co Cobalt 27 59 Ni Nickel 28 64 Cu Copper 29 65 Zn Zinc 30 70 Ga Gallium 31 27 Al Aluminium 13 11 B Boron 5 12 C Carbon 6 14 N Nitrogen 7 16 O Oxygen 8 19 F Fluorine 9 28 Si Silicon 14 31 P Phosphorus 15 32 S Sulfur 16 35.5 Cl Chlorine 17 40 Ar Argon 18 20 Ne Neon 10 4 He Helium 2 73 Ge Germanium 32 75 As Arsenic 33 79 Se Selenium 34 80 Br Bromine 35 84 Kr Krypton 36 39 K Potassium 19 88 Sr Strontium 38 89 Y Yttrium 39 91 Zr Zirconium 40 93 Nb Niobium 41 96 Mo Molybdenum 42 Tc Technetium 43 101 Ru Ruthenium 44 103 Rh Rhodium 45 106 Pd Palladium 46 108 Ag Silver 47 112 Cd Cadmium 48 115 In Indium 49 119 Sn Tin 50 122 Sb Antimony 51 128 Te Tellurium 52 127 I Iodine 53 131 Xe Xenon 54 137 Ba Barium 56 139 La Lanthanum 57 * 178 Hf Hafnium 72 181 Ta Tantalum 73 184 W Tungsten 74 186 Re Rhenium 75 190 Os Osmium 76 192 Ir Iridium 77 195 Pt Platinum 78 197 Au Gold 79 201 Hg Mercury 80 204 Tl Thallium 81 207 Pb Lead 82 209 Bi Bismuth 83 Po Polonium 84 At Astatine 85 Rn Radon 86 Fr Francium 87 227 Ac Actinium 89 9 Be Beryllium 4 I II III IV V VI VII 0 85 Rb Rubidium 37 133 Cs Caesium 55 226 Ra Radium 88 The volume of one mole of any gas is 24 dm3 at room temperature and pressure (r.t.p.). a X b a = relative atomic mass X = atomic symbol b = proton (atomic) number Key *58-71 Lanthanoid series 90-103 Actinoid series DATA SHEET The Periodic Table of the Elements

UNIVERSITY OF CAMBRIDGE INTERNATIONAL EXAMINATIONS International General Certificate of Secondary Education MARK SCHEME for the October/November 2010 question paper for the guidance of teachers 0654 CO-ORDINATED SCIENCES 0654/33 Paper 3 (Extended Theory), maximum raw mark 100 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. • CIE will not enter into discussions or correspondence in connection with these mark schemes. CIE is publishing the mark schemes for the October/November 2010 question papers for most IGCSE, GCE Advanced Level and Advanced Subsidiary Level syllabuses and some Ordinary Level syllabuses. www.XtremePapers.com

Page 2 Mark Scheme: Teachers’ version Syllabus Paper IGCSE – October/November 2010 0654 33 © UCLES 2010 1 (a) (i) reactants used up / no more chemical reaction possible ; [1] (ii) car batteries are (re)chargeable / (re)charged by car engine ; [1] (b) (i) it is a conductor / contains or provides electrolyte ; [1] (ii) magnesium and copper ; the higher the difference in reactivity the higher the voltage ; [2] (c) (i) 11O2 ;; (formula and balanced) [2] (ii) reference to one specified pollutant e.g. CO, CO2, NOx, SO2, O3, particulates, smog ; effect of specific pollutant ; no pollutants produced when normal engine switched off / electric motors do not pollute ; more slow-moving traffic in towns so normal engine more likely to be switched off / owtte ; [3] [Total: 10] 2 (a) (i) A chloroplast ; (accept nucleus) B cell wall ; (accept cell membrane) [2] (ii) have cell walls / B ; have chloroplasts / A ; (accept) have large vacuoles ; [max 2] (b) (i) more leaves / more surface area, on Q ; more transpiration / more water lost from leaves ; so more water taken up (into the plant stem) ; [3] (ii) water level would go down faster ; (higher temperature) increases rate of transpiration ; because faster diffusion / faster rate of evaporation ; because higher kinetic energy of water molecules ; [max 3] [Total: 10]

Page 3 Mark Scheme: Teachers’ version Syllabus Paper IGCSE – October/November 2010 0654 33 © UCLES 2010 3 (a) (i) radioactive decay: breakdown of an unstable nucleus ; half-life: time taken for half of (mass of) an isotope to decay / time taken for, count rate / radioactivity, to halve ; [2] (ii) 4 half lives ; so 4 × 105 seconds = 420 seconds / 7 minutes ; [2] (b) 1. use ; 2. description of effect of radiation; e.g. cancer treatment ; radiation destroys cancerous cells ; e.g. tracers ; radioactive substance can be followed around body ; [2] [Total: 6] 4 (a) (i) differences between individuals ; distinct categories / words to that effect ; [2] (ii) genes alone ; environment tends to give continuous variation ; ref. to allele frequency / ref. to different blood groups in same environment / other good detail; [max 2] (b) (i) any suitable ; (almost anything except age, sex and blood groups) [1] (ii) y-axis labelled, number / percentage / frequency, of people ; x-axis labelled with name of feature and arrow on axis or scale with numbers ; curve / histogram, drawn showing approximately normal distribution ; [3] (c) ref. to selection pressure / named agent of selection ; idea that individuals with a particular variation more likely to survive ; so (individuals with this variation) more likely to reproduce ; genes / alleles, causing this variation more likely to be passed on to offspring ; so this variation becomes more common, in successive generations / over time ; [4] [Total: 12]

Page 4 Mark Scheme: Teachers’ version Syllabus Paper IGCSE – October/November 2010 0654 33 © UCLES 2010 5 (a) A2 0.30 (A) and A3 0.30 (A) ; V1 6 (V) and V2 6 (V) ; [2] (b) (i) V/I ; = 1 / 0.6 = 1.67 Ω ; accept calculation from gradient [2] (ii) current is not proportional to voltage ; the lamp gets hot / its resistance changes ; [2] (iii) a straight line through origin with positive gradient ; [1] (c) lamp does not light / flashes once ; lamp lights ; (somewhere –) a.c. needed for transformer to work ; [3] [Total: 10] 6 (a) (i) (P) full outer shell ; [1] (ii) (Q) metal because, it is a conductor / has 2e– in outer shell / is in group 2 ; liquid because melting point below 20 °C (but boiling point above 20 °C) ; OR (S) metal because it is a conductor / has 1e– in outer shell / is in group 1 ; OR (R) liquid because melting point below 20 °C (but boiling point above 20 °C) ; [2] (iii) (T) R is liquid but T is solid at room temperature / T has higher melting point and boiling point / T is less volatile / vice versa ; shows that T is below R in Group 7 / T from higher period number / has larger atoms / vice versa ; [2] (b) (i) outer electron lost from S and transferred to outer shell of R ; S is now a positive ion and R is a negative ion ; ions (of opposite charge) attract / bond ; [max 2] (ii) compound has a giant (ionic) / lattice structure ; strong, forces (of attraction) between ions / ionic bonds; very many ions so very many bonds to be broken ; much, energy / heat, needed to, separate ions / break the structure / overcome forces ; [max 3] (c) electrolysis ; potassium is a very reactive metal ; [2] [Total: 12]

Page 5 Mark Scheme: Teachers’ version Syllabus Paper IGCSE – October/November 2010 0654 33 © UCLES 2010 7 (a) (distance covered in one minute =) 18 × 60 = 1080 m ; (work = F × d =) 1000 × 1080 = 1 080 000 J ; ecf [2] (b) (i) force = mass × acceleration / (acceleration =) force / mass ; acceleration = 10 000 / 1200 = 8.3 m / s2 ; [2] (ii) acceleration = (change in) speed / time ; time = 18/8.3 = 2.17 s ; ecf [or 2.2 s, A 2.16 s] [2] (c) (i) 0.12 m2 ; [1] (ii) (pressure = force / area =) 18000 / 0.12 = 150 000 N / m2 / Pa ; ecf [1] (iii) (force =) 150 000 × 0.01 = 1 500 N ; ecf [1] [Total: 9] 8 (a) A to intercostal muscle or diaphragm ; B to somewhere within a lung (not bronchus or bronchiole) ; C to diaphragm ; [3] (b) leaves from right ventricle and returns to left atrium ; from heart to lungs in pulmonary artery ; through capillaries in lungs ; from lungs to heart in pulmonary vein ; [3 max] (c) in red blood cells ; as oxyhaemoglobin / combined with haemoglobin ; [2] (d) from mother’s blood ; by diffusion ; through the placenta ; to fetus, in umbilical cord / through umbilical vein ; [max 3] [Total: 11]

Page 6 Mark Scheme: Teachers’ version Syllabus Paper IGCSE – October/November 2010 0654 33 © UCLES 2010 9 (a) (i) (atmospheric) nitrogen converted into, nitrogen compounds / nitrate / ammonium / ammonia ; [1 point] (nitrogen fixing) bacteria ; in soil / on root nodules ; OR atmospheric nitrogen combines with oxygen / nitrogen oxides form ; in thunderstorms / (using energy) from lightning ; OR nitrogen combines with hydrogen / converted to ammonia ; in industry / in Haber Process ; [max 3] (ii) nitrogen too unreactive / too much energy needed to break bonds in nitrogen molecules ; [1] (b) (i) 0.05 ; [1] (ii) states that mass = moles × molar mass / 0.05 × 132 ; 6.6 g ; (unit required) [2] (c) (i) glucose molecules join together / reference to glucose being a monomer ; to form long chains / to form a polymer ; [2] (ii) solution is, transparent / see-through ; starch solution is, not transparent / translucent / cloudy ; light (rays) not, scattered / deviated, by the solution / are scattered by the solution ; [3] [Total: 12] 10 (a) (kinetic energy =) ½ mv2 ; = ½ × 70 × 10 × 10 ; = 3500 J ; [3] (b) (i) energy needed to turn liquid into gas ; particles need to separate / overcome forces between them ; energy / heat, gained from, surroundings / skin / body ; [max 2] (ii) shiny foil traps layer of air around body, stops convection ; air is a good insulator / poor conductor ; shiny foil is a poor radiator of heat ; shiny foil reflects radiation back ; heat can still escape by conduction ; [max 3] [Total: 8]