Cambridge IGCSE Sciences - Co-ordinated (Double) 0654 — 2014 Oct/Nov Paper 2 · Variant 3

This document consists of 31 printed pages and 1 blank page. DC (SJF/SW) 99828 © UCLES 2014 [Turn over * 8 5 2 3 7 8 3 0 1 5 * CO-ORDINATED SCIENCES 0654/23 Paper 2 (Core) October/November 2014 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 an HB soft pencil for any diagrams, graphs, tables or rough working. 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. A copy of the Periodic Table is printed on page 32. 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. Cambridge International Examinations Cambridge International General Certificate of Secondary Education

2 0654/23/O/N/14 © UCLES 2014 1 Fig. 1.1 shows what happens when a small piece of potassium metal reacts with chlorine gas inside a container. clouds of particles made of a white solid container initially full of chlorine gas flames potassium Fig. 1.1 When the reaction has finished, particles of a white solid compound are left in the container. (a) (i) Suggest the name of the white solid compound. …[1] (ii) Fig. 1.2 shows diagrams of a potassium atom and a chlorine atom. potassium atom chlorine atom Fig. 1.2 Describe what happens to these atoms when they change into ions. … … …[2]

3 0654/23/O/N/14 © UCLES 2014 [Turn over (b) A chemical change occurs when an electrical current passes through a solution of the compound copper chloride. Fig. 1.3 shows apparatus that can be used to investigate this chemical change. d.c. power supply switch carbon electrodes + – Fig. 1.3 (i) Name the process which occurs in the apparatus shown in Fig. 1.3 when the switch is closed. …[1] (ii) On Fig. 1.3 use label lines to label the cathode and the electrolyte. [2] (iii) When the switch is closed, bubbles of chlorine appear on the surface of the anode. Describe a safe chemical test for chlorine. … …[2]

4 0654/23/O/N/14 © UCLES 2014 (c) A student investigates whether there is any change in the mass of the electrodes during the process shown in Fig. 1.3. She uses the apparatus shown in Fig. 1.3 and her results are shown in Table 1.1. Table 1.1 electrode mass before the switch is closed / g mass after the switch has been closed for some time / g anode 48.3 48.3 cathode 47.6 47.9 (i) State the changes in mass of the electrodes during the experiment. … …[1] (ii) Explain the results obtained for the cathode. … …[1]

5 0654/23/O/N/14 © UCLES 2014 [Turn over 2 Fig. 2.1 shows the chromosomes from the nucleus of a single cell of a human male. Fig. 2.1 (a) (i) State the number of chromosomes that can be seen in Fig. 2.1. …[1] (ii) On Fig. 2.1, draw a circle around the Y chromosome. [1] (b) Chromosomes carry genes. Define a gene. … … …[2]

6 0654/23/O/N/14 © UCLES 2014 (c) Complete the genetic diagram below to explain why, in a human population, equal numbers of male and female babies should be expected. parents phenotypes sex chromosomes gametes chromosomes and phenotypes of offspring female XX and and male XY male gametes female gametes … ratio of male to female [4]

7 0654/23/O/N/14 © UCLES 2014 [Turn over (d) In sea turtles, the sexes of the offspring are not determined by chromosomes. Instead, sex depends on the temperature at which the eggs are incubated. Fig. 2.2 shows this effect. 100 75 50 25 0 25 27 29 incubation temperature / °C 31 33 percentage of eggs that hatch into females Fig. 2.2 (i) Describe the effect of temperature on the percentage of eggs that hatch into females. … …[1] (ii) State the temperature at which equal numbers of male and female offspring are produced. …°C [1] (iii) Use the information in Fig. 2.2 to predict how global warming will affect the sea turtle population. Explain your answer. … … …[2]

8 0654/23/O/N/14 © UCLES 2014 3 (a) A motorcycle is driven along a straight road. Fig. 3.1 shows a speed/time graph for the motion of the motorcycle from the time the rider sees a car approaching and gradually slows down. 14 12 10 8 6 4 2 0 0 1 2 3 4 5 6 7 8 9 10 time / s speed m / s Fig. 3.1 (i) State the speed at which the driver was travelling before he slowed down. …m / s [1] (ii) State whether the motorcycle stopped during the period of ten seconds shown in Fig. 3.1. Explain your answer. … …[1] (b) The motorcycle rider notices that the sound from a car’s engine becomes louder as the car approaches and drops in pitch as the car passes. Describe these changes in terms of the frequency and amplitude of sound waves released. becomes louder … … has a lower pitch … …[2]

9 0654/23/O/N/14 © UCLES 2014 [Turn over (c) The motorcycle has one headlamp, connected to a 12 V battery. The headlamp takes a current of 4 A. Calculate the resistance of the headlamp. State the formula that you use, show your working and state the unit of your answer. formula working resistance = … unit … [3] (d) As the motorcycle drives along, the temperature of the air in the tyres increases. By referring to the motion of molecules in air, explain why this results in an increased tyre pressure. … … … …[3]

10 0654/23/O/N/14 © UCLES 2014 (e) The metal bodywork of the motorcycle can be painted using electrostatic paint spraying. In electrostatic paint spraying, the surface being painted is given a negative electric charge. The paint particles emerge from the paint sprayer carrying a positive charge. Fig. 3.2 shows part of a motorcycle frame being painted. Fig. 3.2 (i) Suggest why more paint sticks to the charged frame than to an uncharged frame. … …[1] (ii) The motorcycle is painted evenly. An even coat of paint is achieved because the paint particles repel each other. Explain why the particles repel each other. … …[1]

11 0654/23/O/N/14 © UCLES 2014 [Turn over Please turn over for Question 4.

12 0654/23/O/N/14 © UCLES 2014 4 (a) Define the term transpiration. … … …[2] (b) Fig. 4.1 shows xylem vessels from the stem of a plant as seen in longitudinal section. cell wall xylem vessel Fig. 4.1 (i) On Fig. 4.1 draw an arrow to show the direction in which water flows through the xylem vessel. [1] (ii) Name one other substance, apart from water, that is transported through xylem vessels. …[1]

13 0654/23/O/N/14 © UCLES 2014 [Turn over (c) Fig. 4.2 shows a stem and a root in transverse section. On the stem, the positions of the xylem and the phloem tissues have been labelled. transverse section of stem transverse section of root phloem xylem Fig. 4.2 (i) Complete the diagram of the root by drawing in the positions of the xylem and the phloem tissues and labelling them. [3] (ii) State the function of the phloem. …[1] (d) Plants absorb water from the soil. Name the plant cells that take up most of this water. … [1]

14 0654/23/O/N/14 © UCLES 2014 5 A student investigates the reactions between dilute hydrochloric acid and five substances. Fig. 5.1 shows the five substances contained in test-tubes A to E. A magnesium ribbon B zinc C copper D calcium carbonate E sodium hydrogencarbonate Fig. 5.1 She adds dilute hydrochloric acid to each tube. Her observations and temperature measurements are shown in Table 5.1. Table 5.1 test-tube observations temperature of the reactants before reaction / °C temperature of the mixture in the test-tube after a short time / °C A gas given off quickly 18 45 B gas given off slowly 18 19 C no gas produced 18 D gas given off quickly 18 20 E gas given off quickly 18 11 (a) (i) Name the gas given off when dilute hydrochloric acid is added to test-tubes A and B. …[1] (ii) Describe a test and its result for the gas you have named in (a)(i). test … result …[1]

15 0654/23/O/N/14 © UCLES 2014 [Turn over (iii) The pH of the dilute hydrochloric acid before reacting is 2. Predict the pH of the solution in test-tube D after reaction. Explain your answer. prediction … explanation … … …[2] (b) When substances are mixed together, a change in temperature is evidence that a chemical reaction occurs. (i) Suggest the temperature of the mixture in test-tube C after a short time. Write your answer in Table 5.1. [1] (ii) Explain your answer to (b)(i). … …[1] (iii) State and explain in which test-tube, A, B, C, D or E, an endothermic reaction occurs. test-tube … explanation … …[1] (c) Suggest two possible reasons why gas is given off more quickly in test-tube A than in B. 1 … … 2 … …[2]

16 0654/23/O/N/14 © UCLES 2014 6 (a) Infra-red waves can pass through optical fibres. Fig. 6.1 shows a length of optical fibre. An infra-red ray goes in at one end and emerges at the other end. Fig. 6.1 On Fig. 6.1, use a ruler to draw its path along the optical fibre. [2] (b) (i) State what is transferred by all electromagnetic waves. …[1] (ii) γ-radiation is also part of the spectrum of electromagnetic waves. State one difference between γ-radiation and infra-red radiation. … …[1] (c) Fig. 6.2 shows an experiment to investigate infra-red radiation. can A can B radiant heater dull black surface shiny silver surface lid lid d d Fig. 6.2 Two similar cans A and B contain equal amounts of water which start off at the same temperature. Can A has a shiny silver surface and can B has a dull black surface. A thermometer is placed into each can. The cans stand on cork mats and are placed at the same distance d from a radiant heater emitting infra-red radiation. The temperature of the water is measured every minute for twelve minutes.

17 0654/23/O/N/14 © UCLES 2014 [Turn over Fig. 6.3 shows how the temperature of the water changes for the two cans. 0 2 4 6 8 10 12 40 30 20 10 0 time / minutes temperature / °C can A can B Fig. 6.3 (i) State the starting temperature of the water in both cans. …°C [1] (ii) Explain why the two cans are placed on cork mats. …[1] (iii) Describe how the temperature changes are different for the two cans. … … …[1] (iv) Suggest reasons for your answer to (c)(iii). … … …[2]

18 0654/23/O/N/14 © UCLES 2014 7 Fig. 7.1 shows the concentration of carbon dioxide in a muscle cell of an athlete before, during and after a period of exercise. 0 0.5 1 1.5 2 2.5 3 3.5 time / minutes concentration of carbon dioxide period of exercise Fig. 7.1 (a) (i) Name the process that produces carbon dioxide in cells. …[1] (ii) Complete the word equation for this process. + + carbon dioxide [2] (b) State the time in Fig. 7.1 at which the carbon dioxide concentration is lowest. …min [1] (c) During exercise, the blood flow to the muscles increases. Explain why this increased blood flow is important during exercise. … … … …[2]

19 0654/23/O/N/14 © UCLES 2014 [Turn over (d) Training increases the number of red blood cells in an athlete’s body. Suggest how this affects the amount of lactic acid produced when an athlete is sprinting. Explain your answer. … … …[2]

20 0654/23/O/N/14 © UCLES 2014 8 (a) A spillage of a radioactive substance occurs in a store for radioactive materials. The activity due to normal background radiation is 100 counts per minute. After the spillage, the activity in the store rises to 900 counts per minute. (i) State the meaning of the term background radiation. … …[1] (ii) Write down the increase in activity produced by the spilled material. … counts per minute [1] (iii) The pie chart in Fig. 8.1 shows the proportion of the average background radiation that comes from all sources in the United Kingdom. radon gas from the ground 50.0% ground and buildings 14.5% medical 14.0% cosmic rays 10.0% food and drink 11.0% nuclear power 0.5% Fig. 8.1 Use the pie chart to explain why doubling the amount of power generated from nuclear sources would only produce a relatively small increase in background radiation. … …[1] (b) Apart from cost, give one advantage and one disadvantage of an oil-fired power station compared to a nuclear power station. advantage … … disadvantage … …[2]

21 0654/23/O/N/14 © UCLES 2014 [Turn over (c) Electricity supplied to a house is used to produce light. The lighting circuits in a house are constructed so that the lamps are connected in a parallel circuit and not a series circuit. (i) Draw simple circuit diagrams to show the difference between a series circuit and a parallel circuit. Each circuit should include a power source (a cell). [2] (ii) State two advantages of connecting lamps in parallel in a lighting circuit. 1 … … 2 … …[2]

22 0654/23/O/N/14 © UCLES 2014 9 Fig. 9.1 shows molecules of ethane, ethene and ethanol. C H H ethane H H H H H H O H H H H H H H H C C C C C ethene ethanol Fig. 9.1 (a) (i) State and explain which of these compounds are hydrocarbons. compounds … explanation … …[2] (ii) State and explain which one of the three compounds named above is an unsaturated compound. compounds … explanation … …[1] (b) (i) State one use of ethanol. …[1] (ii) In industry, ethanol is made in a chemical reaction involving ethene. Name the substance that reacts with ethene to produce ethanol. …[1] (iii) The reaction in (b)(ii) needs a catalyst. State the meaning of the term catalyst. … … …[2]

23 0654/23/O/N/14 © UCLES 2014 [Turn over (c) Ethene is a colourless gas that reacts to form poly(ethene) which is a white solid. (i) Describe what happens when ethene molecules react to form poly(ethene) molecules. Draw a diagram to help you answer this question. Use the symbol E to show an ethene molecule. … …[2] (ii) State the full name of the type of chemical reaction that occurs in (c)(i). …[2]

24 0654/23/O/N/14 © UCLES 2014 10 (a) Fig. 10.1 represents some waves on water. Fig. 10.1 (i) On Fig. 10.1 label with an arrow ( ) one wavelength. [1] (ii) The waves have a frequency of 0.2 Hz. Explain what is meant by a frequency of 0.2 Hz. … …[1] (iii) Water waves are transverse waves and sound waves are longitudinal waves. Describe how a transverse wave is different from a longitudinal wave. You may draw a labelled diagram if it helps your answer. … … …[2]

25 0654/23/O/N/14 © UCLES 2014 [Turn over (b) A large meteorite falls into the sea. (i) The meteorite produces a wave which travels at a speed of 5.6 m / s. Calculate the time taken by the wave to travel 33 600 m. State the formula that you use and show your working. formula working time = …s [2] (ii) The meteorite is a solid and the sea water is a liquid. Complete Fig. 10.2 to show the arrangement of particles in a liquid. The diagram for a solid has been done for you. solid liquid [2] Fig. 10.2 (iii) The mass of the meteorite is 32 000 kg and its volume is 4 m3. Calculate the density of the meteorite in kg / m3. State the formula that you use and show your working. formula working density = … kg / m3 [2]

26 0654/23/O/N/14 © UCLES 2014 11 Fig. 11.1 shows two liver cells, as seen under a light microscope. X Y A B Fig. 11.1 (a) Name the structures labelled A and B. A … B … [2] (b) State two functions of liver cells. 1 … 2 …[2] (c) Give three ways in which a plant palisade cell differs from a liver cell. 1 … 2 … 3 …[3] (d) In Fig. 11.1, the actual height of the cells along the line X–Y is 0.03 mm. Calculate the magnification of the drawing. magnification = …[2]

27 0654/23/O/N/14 © UCLES 2014 [Turn over (e) Name two of the blood vessels that are associated with the liver, and outline their function. vessel 1 … function … vessel 2 … function … [2]

28 0654/23/O/N/14 © UCLES 2014 12 (a) The Periodic Table lists the elements in order of their proton numbers. Fig. 12.1 shows the positions of the first eighteen elements. The letters are not the chemical symbols of the elements. N L M I II III IV V VI VII 0 P O Fig. 12.1 (i) State the meaning of the terms proton number and nucleon number (mass number). proton number … … nucleon number … …[2] (ii) Predict and explain whether element N has a higher or lower melting point than element P. … …[1] (iii) State and explain which other element in Fig. 12.1 has chemical properties that are very similar to those of element O. element … explanation … …[2]

29 0654/23/O/N/14 © UCLES 2014 [Turn over (b) Carbon dioxide is a gas at room temperature and contains molecules that have the chemical formula CO2. State the type of chemical bonding that joins the atoms together in a molecule of carbon dioxide. Give a reason for your choice. type of bonding … reason … …[2]

30 0654/23/O/N/14 © UCLES 2014 (c) A student investigates how much carbon dioxide gas is contained in a carbonated (fizzy) drink. He measures the mass of a full bottle of fizzy drink. cap balance bottle containing fizzy drink He shakes the bottle. He releases the carbon dioxide by carefully unscrewing the cap. He measures the mass of the bottle and cap, and liquid without the carbon dioxide. His results are shown in Table 12.1. Table 12.1 mass of bottle filled with fizzy drink / g mass of bottle and cap, and liquid without carbon dioxide / g volume of the liquid / cm3 526.2 524.0 500.0 (i) State the mass of carbon dioxide that was released from the fizzy drink. Show your working. mass = …g [1] (ii) Calculate the mass of carbon dioxide that is dissolved in 1.0 dm3 of the fizzy drink. Show your working. mass = …g [2]

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32 0654/23/O/N/14 © UCLES 2014 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. 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. Group The Periodic Table of the Elements 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 91 238 231 147 237 244 243 247 247 251 252 257 258 259 260 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 82 209 209 210 222 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 55 226 223 Ra Radium 88 a X b a = relative atomic mass X = atomic symbol b = atomic (proton) number Key DATA SHEET * 58–71 Lanthanoid series † 90–103 Actinoid series The volume of one mole of any gas is 24dm3 at room temperature and pressure (r.t.p.).

® IGCSE is the registered trademark of Cambridge International Examinations. CAMBRIDGE INTERNATIONAL EXAMINATIONS Cambridge International General Certificate of Secondary Education MARK SCHEME for the October/November 2014 series 0654 CO-ORDINATED SCIENCES 0654/23 Paper 2 (Core Theory), maximum raw mark 120 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 2014 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 IGCSE – October/November 2014 0654 23 © Cambridge International Examinations 2014 1 (a) (i) potassium chloride ; [1] (ii) potassium (atom) loses (an) electron / becomes positively charged ; chlorine atom gains (one) electron / becomes negatively charged ; the ions become bonded together / form a compound ; the ions become bonded together / form a compound ; [max 2] (b) (i) electrolysis ; [1] (ii) label line to negative electrode (not the connecting wire) ; label line into the liquid shown in the container ; [2] (iii) damp litmus / indicator paper ; is bleached ; [2] (c) (i) anode suffered no change in mass and cathode gained (0.3 g) mass ; [1] (ii) copper deposited on the cathode (adding mass) ; [1] [Total: 10] 2 (a) (i) 46 ; [1] (ii) Y-chromosome correctly circled ; [1] (b) units of heredity / can be passed on to the next generation ; code for (specific) proteins / code for control of a particular cell activity ; are regions / part of DNA ; [max 2]

Page 3 Mark Scheme Syllabus Paper Cambridge IGCSE – October/November 2014 0654 23 © Cambridge International Examinations 2014 (c) gametes correctly shown X, (X), X, Y ; parents gametes correctly placed in table ; offspring genotypes correctly shown ; 1:1, 2:2 or 50 / 50 ; [4] (d) (i) as temperature increases percentage of females increases; [1] (ii) 29 (°C); [1] (iii) more females would hatch / ORA ; reduced fertility of the population / owtte ; [2] [Total: 12] 3 (a) (i) 12 (m / s) ; [1] (ii) no – speed never drops to x-axis (0); [1] (b) becomes louder – amplitude increases ; lower pitch – frequency decreases ; [2] (c) (R) = I V ; = 4 12 = 3 ; Ω ; [3] parents phenotypes sex chromosomes gametes chromosomes and phenotypes of offspring female XX and male XY and male gametes female gametes ratio … X X X Y X X X Y XX female XY male XX female XY male 1 : 1 XX (female) XX (female) XY (male) XY (male)

Page 4 Mark Scheme Syllabus Paper Cambridge IGCSE – October/November 2014 0654 23 © Cambridge International Examinations 2014 (d) (as temperature increases) kinetic energy / velocity of molecules increases ; increased force / energy of collisions ; increased frequency of collisions ; collisions with walls of tyre ; [max 3] (e) (i) opposite charges attract ; [1] (ii) like charges repel ; [1] [Total: 12] 4 (a) evaporation of water ; from (surfaces of) mesophyll / palisade cells ; (followed by) loss of water (vapour) through stomata ; [max 2] (b) (i) arrow drawn going upwards ; [1] (ii) nitrate / magnesium / named mineral ion ; [1] (c) (i) star-shaped (cross shaped) xylem tissue in middle, phloem in the angles ; xylem correctly labelled ; phloem correctly labelled ; [3] (ii) translocation / transport of sugar / sucrose / amino acids ; [1] (d) root hair cells ; [1] [Total: 9] transverse section of stem transverse section of root phloem phloem xylem xylem

Page 5 Mark Scheme Syllabus Paper Cambridge IGCSE – October/November 2014 0654 23 © Cambridge International Examinations 2014 5 (a) (i) hydrogen ; [1] (ii) lighted splint causes ‘pop’ ; [1] (iii) greater than 2 but less than 7 ; some of the acid has reacted / been used up / concentration of acid reduced ; so acid concentration is lower / lower concentration means higher pH ; [max 2] (b) (i) 18 (°C) ; [1] (ii) copper does not react with dilute acid / there is no reaction ; [1] (iii) (E) – no mark the temperature decreases ; [1] (c) in tube A the metal has higher surface area / greater degree of division ; (metal in) tube A magnesium is more reactive than zinc / or could just say metal in A more reactive ; reaction in A is more exothermic so higher temperature produces higher rate of reaction / reacts faster ; [max 2] [Total: 9] 6 (a) straight lines drawn (bouncing off fibre walls) which reach the end of the optical fibre ; angles approximately correct ; [2] (b) (i) energy ; [1] (ii) γ more ionising / γ higher frequency / lower wavelength / higher energy ; [1] (c) (i) 13 (°C) ; [1] (ii) cork mat is insulator / prevents conduction ; [1] (iii) B – rises more than A / gets hotter than A ; [1] (iv) idea of different surfaces ; dark / dull absorb more heat etc. ; [2] [Total: 9]

Page 6 Mark Scheme Syllabus Paper Cambridge IGCSE – October/November 2014 0654 23 © Cambridge International Examinations 2014 7 (a) (i) respiration ; [1] (ii) glucose + oxygen ; water ; [2] (b) 3.2 to 3.3 minutes ; [1] (c) more oxygen ; more glucose ; for (muscle) respiration ; more CO2 removed ; [max 2] (d) blood carries more oxygen ; better oxygen supply to muscles / for respiration / have more aerobic respiration / have less anaerobic respiration ; [2] [Total: 8] 8 (a) (i) background radiation – (ionising) radiation constantly present in the natural environment of the Earth (which is emitted by natural and artificial sources) ; [1] (ii) 800 (cpm) ; [1] (iii) background radiation from nuclear power generation very small percentage etc. ; [1] (b) advantage – no decommissioning costs / no radiation problems ; disadvantage – uses up valuable fossil fuels / uses non-renewable fuels (if explained) / atmospheric pollution / CO2 produced / contributes to global warming ; [2] (c) (i) diagram showing a series circuit ; diagram showing a parallel circuit ; [2] (ii) if one lamp does not work it will not affect the other lamps ; lamps can be switched on and off independently ; each lamp gets full mains voltage / full brightness ; [max 2] [Total: 9]

Page 7 Mark Scheme Syllabus Paper Cambridge IGCSE – October/November 2014 0654 23 © Cambridge International Examinations 2014 9 (a) (i) ethane and ethene ; contain only hydrogen and carbon ; [2] (ii) (ethene) contains (C to C) double bond / does not contain maximum possible hydrogen ; [1] (b) (i) solvent / fuel / in drinks / other correct ; [1] (ii) steam ; (allow water vapour and water) label line into the liquid shown in the container ; [1] (iii) substance that speeds up a reaction ; remains (chemically) unchanged / is not used up ; [2] (c) (i) ethene molecules join together / double bond breaks ; to form a long chain molecule (at least 3 molecules) ; [2] (ii) addition ; polymerisation ; [2] [Total: 11] 10 (a) (i) distance between two identical points on two successive waves ; [1] (ii) 0.2 waves are produced per second / pass a fixed point per second ; the ions become bonded together / form a compound ; [1] (iii) vibrations in different directions ; longitudinal vibrations move in same direction as wave / energy moves ; transverse vibrations move at right angles to direction that wave / energy moves ; [max 2] (b) (i) (time) = speed distance ; = 5.6 33600 = 6000 (s) ; [2] (ii) random arrangement (at least 10 particles shown) ; most touching ; label line into the liquid shown in the container ; [max 2] (iii) (density) = volume mass ; = 4 32000 = 8000 (kg / m3) ; [2] [Total: 10]

Page 8 Mark Scheme Syllabus Paper Cambridge IGCSE – October/November 2014 0654 23 © Cambridge International Examinations 2014 11 (a) A = cell membrane ; B = nucleus ; [2] (b) produces bile ; stores glycogen ; controls blood glucose ; breaks down poisons / toxins / alcohol ; destroys hormones ; removes products of red blood cell breakdown ; produces urea ; [max 2] (c) cell wall ; chloroplasts ; vacuole ; elongated / more regular shape ; no centrioles ; [max 3] (d) 0.03 45 ; = (x) 1500 ; [2] (e) vessel – hepatic artery function – transport of oxygen for reactions that take place; vessel – (hepatic) portal vein function – transport absorbed food / nutrients; vessel – hepatic vein function – removing waste products / deoxygenated blood; [max 2] [Total: 11] 12 (a) (i) number of protons in atom / nucleus ; total of protons and neutrons in atom / nucleus ; total of protons and neutrons in atom / nucleus ; contain only hydrogen and carbon ; [2] (ii) (higher) N is a metal / solid P is a gas ; the ions become bonded together / form a compound; [1] (iii) L ; idea that L and O in same group / properties similar within groups / same number of outer shell electrons ; [2] (b) covalent ; reference to two non-metals / gas at room temperature ; [2]

Page 9 Mark Scheme Syllabus Paper Cambridge IGCSE – October/November 2014 0654 23 © Cambridge International Examinations 2014 (c) (i) 526.2 – 524.0 = 2.2 (g); [1] (ii) 1.0 dm3 is 1000 cm3 ; so mass dissolved is 2 × 2.2 = 4.4 (g) ; OR 500 cm3 = 0.5 dm3; 0.5 2.2 = 4.4 (g); [max 2] [Total: 10]