Cambridge IGCSE Science - Combined 0653 — 2014 Oct/Nov Paper 2 · Variant 2

This document consists of 19 printed pages and 1 blank page. DC (CW/AR) 89392/4 © UCLES 2014 [Turn over Cambridge International Examinations Cambridge International General Certificate of Secondary Education * 9 4 0 0 1 2 9 8 5 1 * COMBINED SCIENCE 0653/22 Paper 2 (Core) October/November 2014 1 hour 15 minutes 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 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. A copy of the Periodic Table is printed on page 20. 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 0653/22/O/N/14 © UCLES 2014 1 (a) Copper metal can be extracted from copper oxide by heating it with carbon. The word equation for this reaction is shown below. copper oxide + carbon copper + carbon dioxide Explain why this reaction could be described as a redox reaction. … …[2] (b) Lead can be extracted from lead bromide by electrolysis. Stage 1. Lead bromide crystals are melted. Stage 2. The molten lead bromide is electrolysed. Fig. 1.1 shows the apparatus that could be used for the electrolysis of molten lead bromide. + − d.c. power supply heat … … … Fig. 1.1 (i) Use the following terms to complete the labelling of the diagram in Fig. 1.1. anode cathode electrolyte [2] (ii) Name and describe the appearance of the products that appear at or near the positive electrode, … … the negative electrode. … …[3]

3 0653/22/O/N/14 © UCLES 2014 [Turn over 2 Fig. 2.1 shows a special bicycle used to break the world speed record for a human-powered bicycle. Fig. 2.1 On one run along a measured distance of 200 m, the rider’s speed is 40 m / s. (a) (i) Calculate the time taken by the rider over the measured distance of 200 m. State the formula you use and show your working. formula working time = … s [2] (ii) Calculate the rider’s speed in kilometres per hour (km / h). Show your working. speed = … km / h [2]

4 0653/22/O/N/14 © UCLES 2014 (b) After pedalling at constant speed for 200 m, the rider uses the brakes to stop the bicycle over the next 300 m. On the axes below, sketch the shape of the speed / time graph for this motion. speed time [2] (c) While moving at a constant speed of 40 m / s, the bicycle is moved forward by a constant force of 400 N against the opposing forces. (i) State the magnitude of the opposing forces. Give a reason for your answer. … …[1] (ii) Complete the sequence of energy transfers that occurs during the run. … energy in the rider kinetic energy of the bicycle and rider … energy during braking [2]

5 0653/22/O/N/14 © UCLES 2014 [Turn over 3 (a) Fig. 3.1 shows the human gas exchange system. B A Fig. 3.1 Name structures A and B. A … B … [2] (b) A student investigates his breathing before and after exercise. He measures the number of breaths taken during one minute. He also measures the average volume of one breath during this minute. His results are shown in Table 3.1. Table 3.1 number of breaths per minute average volume of one breath / dm3 at rest 20 0.5 immediately after exercise 35 1.6 Describe two ways in which the breathing of the athlete changes with exercise. 1 … … 2 … …[2]

6 0653/22/O/N/14 © UCLES 2014 (c) The student uses the apparatus in Fig. 3.2 to compare inhaled and exhaled air. The inhaled air passes through the limewater in flask P. The exhaled air passes through the limewater in flask Q. The limewater changes to a milky colour when enough carbon dioxide passes through it. The student breathes in and out of the apparatus until the limewater goes milky in one of the flasks. He times how long this takes. The experiment is done twice, once before exercise and once after exercise. flask P flask Q limewater inhaled air student breathes in and out here exhaled air Fig. 3.2 Table 3.2 shows the results obtained. Table 3.2 observation of limewater in flask P time taken for limewater to change in flask Q / s before exercise no change 20 immediately after exercise no change 4 (i) Use the information in Table 3.2 to compare the carbon dioxide content of inhaled and exhaled air. … …[1]

7 0653/22/O/N/14 © UCLES 2014 [Turn over (ii) Study the times taken for the limewater to turn milky in Table 3.2 before and after exercise. Draw a conclusion from these results. … … …[2] (iii) Suggest why there is no change observed in flask P. … … …[2]

8 0653/22/O/N/14 © UCLES 2014 4 Fig. 4.1 shows the circuit symbols for an electric bell and a push-switch. electric bell push-switch Fig. 4.1 (a) (i) Complete the circuit diagram in Fig. 4.2 for a circuit for a door-bell with a push-switch, powered by a battery with four cells, for the front door of a house. Fig. 4.2 [2] (ii) Add a voltmeter to the completed circuit diagram in Fig. 4.2 to measure the voltage across the battery. [1] (b) The ringing bell emits a sound of frequency 400 Hz. (i) State the meaning of the term frequency. … …[1] (ii) The house owner makes the sound of the bell louder by adding another cell to the battery, but the pitch of the sound from the bell remains unchanged. State the effect this change has on the amplitude and frequency of the sound emitted. effect on the amplitude … … effect on the frequency … …[2]

9 0653/22/O/N/14 © UCLES 2014 [Turn over (c) (i) The voltage provided by the battery is 6 V. When the bell is rung, a current of 2 A flows through the bell. Use the formula R = V I to calculate the resistance of the bell. Show your working and state the unit of your answer. working resistance = … unit … [2] (ii) The house owner adds a second identical bell in the circuit in parallel to the first bell. When the switch is pushed, both bells ring. Suggest the effect the second bell will have on the current taken from the battery when the bells are rung. Give a reason for your answer. … … …[2]

10 0653/22/O/N/14 © UCLES 2014 5 (a) An atom of carbon has a proton (atomic) number 6 and nucleon (mass) number 12. (i) Complete Table 5.1 to show the structure of this carbon atom. Table 5.1 in nucleus outside nucleus number of protons number of neutrons number of electrons [2] (ii) Explain why a carbon atom is electrically neutral. … … …[2] (b) Methane is a carbon compound which is used as a fuel. (i) Suggest a source of methane. …[1] (ii) Write a word equation for the complete combustion of methane. + + [2] (c) Fig. 5.1 shows the structure of a molecule of methane. H H H C H chemical bond Fig. 5.1 (i) State the chemical formula of methane. … [1] (ii) Name the type of chemical bond present in a methane molecule. …[1] (iii) State the number of electrons found in the chemical bond shown in Fig. 5.1. …[1]

11 0653/22/O/N/14 © UCLES 2014 [Turn over 6 Fig. 6.1 shows a method that uses solar energy to purify drinking water. The method is used in hot desert countries. The impure water is heated by the sun and distilled. The pure water is collected separately, while the impurities are left behind. drops of pure water clear plastic cover black-painted base impure water flow Fig. 6.1 (a) State the part of the Sun’s electromagnetic spectrum that heats the water. …[1] (b) Solar energy produces water vapour from the impure water. Explain why water molecules are able to escape more easily from warm water than from cold water. … … …[2] (c) Explain why thermal energy transfer from the Sun only occurs by radiation and not by conduction or convection. … …[1]

12 0653/22/O/N/14 © UCLES 2014 (d) Fig. 6.2 shows a ray of sunlight about to pass through the plastic cover. Draw the path of the ray from the point where it enters the plastic to show what happens at the lower face of the plastic. Indicate the angles of incidence and refraction at the upper face. lower face of plastic upper face of plastic clear plastic cover Fig. 6.2 [3]

13 0653/22/O/N/14 © UCLES 2014 [Turn over 7 (a) Fig. 7.1 shows what happens when a plant is placed near a window where bright light is coming from one side. DWVWDUW DIWHUDIHZGD\V OLJKW OLJKW Fig. 7.1 (i) Name the response shown by the plant. …[1] (ii) Explain why the response shown in Fig. 7.1 is an advantage to the plant. … … …[2] (iii) Using the information in Fig. 7.1 name two characteristics of living things shown by this plant. 1 … 2 …[2]

14 0653/22/O/N/14 © UCLES 2014 (b) A student carries out an experiment to find out more about plant responses. He uses simple shoots and light coming from one side. The results are shown in Table. 7.2. Table 7.2 shoot X shoot X shoot Y shoot Y shoot Z at the start after a few days tip removed light light light light light light shoot Z foil foil tip removed (i) Describe the results shown in Table 7.2. … … …[2] (ii) Suggest a possible conclusion about the control of plant responses in the shoots. Explain your answer. … … …[2]

15 0653/22/O/N/14 © UCLES 2014 [Turn over (c) Animals are able to respond to situations by secreting the hormone adrenaline. Adrenaline is secreted into the blood when an athlete starts to run a race. Suggest how this helps the athlete to run fast. … … …[2]

16 0653/22/O/N/14 © UCLES 2014 8 Some sulfur has become contaminated with a small amount of aluminium powder. (a) A liquid is added to the mixture which dissolves the sulfur. Fig. 8.1 shows how sulfur is separated from the mixture of aluminium and sulfur. aluminium and sulfur mixture liquid sulfur solution aluminium Fig. 8.1 Suggest how the processes of filtration and crystallisation could be used to obtain pure sulfur from the sulfur solution and aluminium. You should draw diagrams to show your arrangement of apparatus. … … … …[3]

17 0653/22/O/N/14 © UCLES 2014 [Turn over (b) Aluminium sulfide is a compound made by heating a mixture of aluminium and sulfur. Aluminium sulfide is a compound of the elements aluminium and sulfur. The left hand column in Fig. 8.2 gives four descriptions of materials. The right hand column shows three different types of materials. Draw a line from each description on the left hand side to the correct material on the right. cannot be broken down into simpler substances compound contains different atoms chemically bonded together element contains more than one type of atom which are not bonded together mixture contains one type of atom Fig. 8.2 [4] (c) (i) When aluminium and sulfur atoms react together, positive aluminium ions and negative sulfide ions are formed. Describe, in terms of electrons, how these ions are formed from atoms. … … …[2] (ii) Aluminium sulfide consists of two aluminium ions to every three sulfide ions. State the chemical formula of aluminium sulfide. …[1]

18 0653/22/O/N/14 © UCLES 2014 9 Fig. 9.1 shows the reproductive system of a female. Fig. 9.1 (a) (i) On Fig. 9.1 use label lines to label the cervix and the vagina. [2] (ii) On Fig. 9.1 use a label line and the letter H to show where haploid cells are found. [1] (b) (i) State the area where fertilisation occurs. …[1] (ii) The fertilised egg cell (the zygote) divides to form a ball of cells. Describe where this ball of cells settles (implants) to continue development into a baby. … …[2] (c) One way in which the human immunodeficiency virus (HIV) can be transmitted is through sexual intercourse. State one other way in which HIV can be transmitted. … …[1]

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20 0653/22/O/N/14 © UCLES 2014 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.). 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.

® 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 0653 COMBINED SCIENCE 0653/22 Paper 2 (Core Theory), maximum raw mark 80 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 0653 22 © Cambridge International Examinations 2014 speed time 1 (a) copper oxide (loses oxygen so) is reduced / copper ions gain electrons ; carbon (gains oxygen so) is oxidised ; [2] (b) (i) electrodes correctly labelled anode and cathode ; electrolyte labelled ; [2] (ii) at the positive electrode bromine and at the negative electrode lead ; lead appears as a, grey / metallic, deposit / bead of molten metal ; bromine, is a brown gas / causes a brown colouration of electrolyte ; [3] [Total: 7] 2 (a) (i) speed = distance/time / (time =)distance / speed ; 200/40 = 5 (s) ; [2] (ii) 40 m/s = 40 × 60 × 60 m/h (= 144 000 m/h) ; 40 × 60 × 60 m/h = 40 × 60 × 60 /1000 km/h = 144 (km/h) ; [2] (b) horizontal straight line ; followed by descending line, straight or curved, to meet time axis ; [2] (c) (i) (400 N – no mark) for constant speed, forces must be equal and opposite (owtte) ; [1] (ii) chemical energy in the rider ; heat/thermal energy during braking ; [2] allow sound [Total: 9]

Page 3 Mark Scheme Syllabus Paper Cambridge IGCSE – October/November 2014 0653 22 © Cambridge International Examinations 2014 3 (a) A trachea ; B bronchiole ; [2] (b) breathing rate increase ; volume / depth (of breathing) increased ; [2] (c) (i) more carbon dioxide in exhaled air / less carbon dioxide in inhaled air ; [1] (ii) (after exercise) exhaled air contains more carbon dioxide / ora ; use of numbers from data (e.g. exhaled air contains about four times as much carbon dioxide) ; [2] (iii) no carbon dioxide present ; not enough carbon dioxide in air to show a result ; [2] [Total: 9] 4 (a) (i) complete series circuit ; battery of 4 cells connected correctly ; [2] (ii) symbol with correct connections (both required) [1] (b) (i) number of vibrations / waves per unit time ; [1] (ii) amplitude increased ; frequency unchanged ; [2] V

Page 4 Mark Scheme Syllabus Paper Cambridge IGCSE – October/November 2014 0653 22 © Cambridge International Examinations 2014 (c) (i) resistance = 6 / 2 = 3 ; (units) ohms /Ω ; [2] (ii) current increased / doubled ; in parallel circuits, the current from the source is larger than the current in each branch / owtte) ; resistance is lower ; [max 2] [Total: 10] 5 (a) (i) in nucleus outside nucleus number of protons 6 0 number of neutrons 6 0 number of electrons 0 6 column correct ; column correct ; [2] (ii) equal numbers of protons and electrons ; equal numbers of positive and negative charges ; protons are positive and electrons are negative ; [max 2] (b) (i) natural gas / petroleum / refinery gas / rice fields / from biodegradation / digestive activity of ruminants ; [1] (ii) methane + oxygen
carbon dioxide + water LHS ; RHS ; [2] (c) (i) CH4 ; [1] (ii) covalent ; [1] (iii) 2 ; [1] [Total: 10]

Page 5 Mark Scheme Syllabus Paper Cambridge IGCSE – October/November 2014 0653 22 © Cambridge International Examinations 2014 6 (a) infra-red ; [1] (b) molecules have more energy so more of them are moving faster (owtte) ; more molecules have enough KE / moving fast enough to escape (from surface) ; [2] (c) need a medium for conduction & convection / no medium in space (owtte) ; [1] (d) Fig 2.2 refracted ray in plastic bent towards normal ; normal drawn at upper face with angles of incidence and refraction correctly marked ; emergent ray parallel to incident ray ; [3] [Total: 7] 7 (a) (i) phototropism ; [1] (ii) more / better absorption of light ; more / better photosynthesis ; any statement about light hitting leaves at right angles / not at an angle ; [max 2] (iii) sensitivity ; movement ; growth ; [max 2] (b) (i) shoot X bends towards the light / responds ; shoots Y and Z do not ; [2] (ii) the tip of the shoot detects the light / controls the response ; because no response occurs when tip is covered/removed ; [2] (c) gives more glucose into blood ; increases pulse rate ; makes more energy available from respiration / speeds up metabolism ; [max 2] [Total: 11] clear plastic cover lower face of plastic upper face of plastic i r

Page 6 Mark Scheme Syllabus Paper Cambridge IGCSE – October/November 2014 0653 22 © Cambridge International Examinations 2014 8 (a) workable filtration equipment ; collection of filtrate ; evaporation ; [3] (b) [4] (c) (i) aluminium (atoms) lose electrons ; sulfur (atoms) gain electrons ; electrons are transferred from aluminium to sulfur (atoms) ;; [max 2] (ii) Al2S3 ; [1] [Total: 10] 9 (a) (i) cervix correctly labelled ; vagina correctly labelled ; [2] (ii) ovary correctly labelled ; [1] (b) (i) oviduct / fallopian tube ; [1] (ii) uterus ; (embedded) in lining ; [2] (c) sharing needles / blood transfusions / avp ; [1] [Total: 7] cannot be broken down into simpler substances contains different atoms chemically bonded together contains more than one type of atom which are not bonded together contains one type of atom. compound element mixture