Cambridge IGCSE Science - Combined 0653 — 2006 Oct/Nov Paper 3 · Variant 1

Centre Number Candidate Number Name UNIVERSITY OF CAMBRIDGE INTERNATIONAL EXAMINATIONS International General Certificate of Secondary Education COMBINED SCIENCE 0653/03 Paper 3 (Extended) October/November 2006 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, graphs, tables or rough working. Do not use staples, paper clips, highlighters, glue or correction fluid. Answer all questions. 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. For Examiner’s Use 1 2 3 4 5 6 7 8 9 10 Total This document consists of 19 printed pages and 1 blank page. IB06 11_0653_03/2RP © UCLES 2006 [Turn over www.XtremePapers.com

2 © UCLES 2006 0653/03/O/N/06 For Examiner's Use 1 (a) The pie chart in Fig. 1.1 shows the energy sources used to generate the electricity in a European country in one year. nuclear coal natural gas hydroelectric oil other fuels other energy sources 25 % 25 % 40 % 3 % 3 % 2 % 2 % hydroelectric oil other fuels other energy sources nuclear coal natural gas Fig. 1.1 (i) Suggest one fuel which could have been included in the 'other fuels' section. [1] (ii) Calculate the percentage of the country’s electricity derived from fossil fuels listed in Fig. 1.1. [1] (b) (i) Transformers are used to increase the voltage before electricity is transmitted. Explain why this is done [1] (ii) Explain why the electricity generated in power stations is normally a.c. and not d.c. [2]

3 © UCLES 2006 0653/03/O/N/06 [Turn over For Examiner's Use (iii) On the grid below sketch a graph to show how the voltage output from an a.c. generator varies with time. time / s voltage / V 0 [2]

4 © UCLES 2006 0653/03/O/N/06 For Examiner's Use 2 Fig. 2.1 shows a human fetus just before birth. placenta A B D C Fig. 2.1 (a) Name structures A to D. A B C D [2] (b) Explain how the developing fetus obtains nutrients while it is in the uterus. [3]

5 © UCLES 2006 0653/03/O/N/06 [Turn over For Examiner's Use (c) After birth, the baby can be breast fed on milk from its mother, or bottle fed on milk made up from a formula. Describe two advantages, apart from cost, of breast feeding a baby. [2] (d) If a mother has AIDS, there is a risk that her baby may be born with HIV and develop AIDS. Explain how this could happen. [2]

6 © UCLES 2006 0653/03/O/N/06 For Examiner's Use 3 A student uses the apparatus shown in Fig. 3.1 to investigate several different chemical reactions. In each reaction, a solid reacts with a solution and a gas is produced. The volume of gas produced in each case can be measured using the gas syringe. gas syringe gas C solution A solid B Fig. 3.1 (a) (i) Table 3.1 lists three experiments in which three different solids react with three different solutions. Complete Table 3.1 by writing in the right hand column the name of the gas C produced in each experiment. Table 3.1 experiment number solution A pH of solution A solid B gas C 1 hydrochloric acid 1.2 calcium carbonate 2 sulphuric acid 1.5 magnesium 3 nitric acid 1.1 sodium hydrogencarbonate [3] (ii) Write the chemical formula of nitric acid. [1] (iii) All aqueous solutions of acids contain hydrogen ions, H+. State which acid in Table 3.1 contains the highest concentration of hydrogen ions. [1]

7 © UCLES 2006 0653/03/O/N/06 [Turn over For Examiner's Use (b) The student then carried out a series of experiments using calcium carbonate and dilute hydrochloric acid. She measured the time taken for 50 cm3 of gas to collect in the gas syringe shown in Fig. 3.1. Her results are shown in Table 3.2. Table 3.2 experiment number time to collect 50 cm3 of gas / s 4 40 5 80 6 20 (i) Explain in which reaction, 4, 5 or 6, the rate of reaction was the greatest. [2] (ii) Suggest and explain, in terms of collisions between particles, one possible difference in the reaction conditions between experiments 5 and 6 which would explain the difference in reaction rate. [2]

8 © UCLES 2006 0653/03/O/N/06 For Examiner's Use 4 A torch contains 3 cells, a switch and a lamp connected in series. (a) The potential difference across each of the cells in the circuit is 1.5 V. (i) State the total potential difference across the three cells. [1] (ii) State the potential difference across the lamp. [1] (b) Fig. 4.1 shows a torch standing on a table. M is the position of the centre of mass of the torch. table A B M Fig. 4.1 (i) What is meant by the term centre of mass? [1] (ii) Explain why the torch is more stable if it stands on end A rather than on end B. Use diagrams in your answer. [2]

9 © UCLES 2006 0653/03/O/N/06 [Turn over For Examiner's Use 5 An athlete ran on a treadmill on three different days. He ran a different distance on each day. Each time, he ran at a speed that he would use if he was running a race of that particular distance. The amount of energy that he used and the volume of oxygen that he consumed was measured during each run. The results are shown in Table 5.1. Table 5.1 distance of run / m total oxygen consumed / dm3 total energy used / kJ mean energy use per metre / kJ 100 10 200 2.0 1500 36 720 0.5 10 000 150 3000 (a) (i) Explain how the oxygen consumed by the athlete was used to provide the energy that he used in the runs. [3] (ii) The amount of energy provided by one dm3 of oxygen was the same in each run. Calculate this value. [1] (b) (i) Calculate the energy used per metre in the 10 000 metre run, and write the answer in Table 5.1. [1] (ii) Describe the relationship shown in the table between the mean energy used per metre and the distance of the run. Suggest a reason for this relationship. [2] (c) At the end of the 100 m run, the athlete carried on breathing very heavily for the next few minutes. Explain why he did this. [3]

10 © UCLES 2006 0653/03/O/N/06 For Examiner's Use 6 Fig. 6.1 shows industrial apparatus used to obtain useful products, A to F, from petroleum (crude oil). petroleum A B C D E F Fig. 6.1 (a) (i) Name the process shown in Fig. 6.1. [1] (ii) State which of the products, A to F, is at the highest temperature when it first comes out of the apparatus in Fig. 6.1. [1] (b) The balanced equation for the complete combustion of methane is shown below. CH4 + 2O2 → CO2 + 2H2O (i) Calculate the relative molecular mass of water. The relative atomic masses of hydrogen and oxygen are 1 and 16 respectively. Show your working. [1] (ii) When 16 g of methane burn, 44 g of carbon dioxide and 36 g of water are formed. Calculate the total mass of products when 32 000 g of methane burn. Show your working. [2]

11 © UCLES 2006 0653/03/O/N/06 [Turn over For Examiner's Use (c) During the complete combustion of 16 g of methane, some chemical bonds are broken and others are formed. Table 6.2 shows some information about the energy changes involved in this reaction. Table 6.2 energy absorbed when chemical bonds are broken energy released when chemical bonds are formed 2632 J 3446 J (i) Name one substance in which bonds are broken during the complete combustion of methane. [1] (ii) Use the information in Table 6.2 to explain why the complete combustion of methane is an exothermic reaction. [1] (d) The displayed formula of ethene is shown below. H C H H C H Describe what happens when ethene undergoes addition polymerisation to form poly(ethene). You may draw a diagram if it helps you to answer this question. [2]

12 © UCLES 2006 0653/03/O/N/06 For Examiner's Use 7 (a) Optical fibres are used to view cavities inside the body. Light is sent down some of the fibres to enable doctors to see what is there. (i) Fig. 7.1 shows an optical fibre with a ray of light travelling down part of it. Draw the path of the ray of light as it travels down the fibre. Fig. 7.1 [1] (ii) Some fibres are used to allow the light to return so that an image can be seen. Why is it important that light does not leak from one fibre to another? [1] (iii) Suggest why optical fibres are now replacing metal wires as the method by which telephone signals are sent. [1]

13 © UCLES 2006 0653/03/O/N/06 [Turn over For Examiner's Use (b) A student carried out an experiment to find the speed of sound in air by watching and listening to a bell being rung. He stood with a timer 1000 m from the bell. student bell tower 1000 m (i) The sound took 3 seconds to travel from the bell to the student. Calculate the speed of sound. Show your working and state the formula that you use. formula used working [2] (ii) Describe how the density of an irregular object such as a bell could be determined. [4]

14 © UCLES 2006 0653/03/O/N/06 For Examiner's Use 8 A gardener found that aphids (greenfly) were feeding on his rose plants. Fig. 8.1 shows an aphid on a rose stem. Fig. 8.1 Aphids feed by using their needle-like mouthparts to pierce the plant stems and leaves. They suck out fluid from the plant’s phloem tubes. (a) (i) Explain why even a small insect such as an aphid can reach the fluid in the phloem tubes. [1] (ii) Explain why the contents of the phloem tubes make a better food source for insects than the contents of the xylem vessels. [2]

15 © UCLES 2006 0653/03/O/N/06 [Turn over For Examiner's Use (b) The gardener decided to spray the plants with a systemic insecticide. An insecticide is a pesticide that kills insects. Systemic pesticides are taken into the plant through its leaves and then transported throughout the plant. (i) Give two advantages of systemic pesticides over other kinds of pesticides. [2] (ii) An alternative method of controlling aphids on rose bushes is to introduce a population of ladybirds to the plants. Ladybirds kill and eat aphids. Give the name for this kind of pest control. [1] (c) Phloem is a tissue. Explain what is meant by this term. [2]

16 © UCLES 2006 0653/03/O/N/06 For Examiner's Use 9 (a) Table 9.1 shows some properties of elements. Write the letter M in the right hand column next to properties which are typical of metallic elements. Table 9.1 can be hammered into different shapes poor conductor of heat is a gas at room temperature (20°C) good conductor of electricity poor conductor of electricity [1] (b) Aluminium is an important metal in Group III of the Periodic Table. State the number of protons in one atom of aluminium. [1]

17 © UCLES 2006 0653/03/O/N/06 [Turn over For Examiner's Use (c) Aluminium is obtained from the compound aluminium oxide by electrolysis. (i) Fig. 9.2 shows diagrams of an aluminium atom and an oxygen atom. Complete the diagrams of the aluminium ion and the oxide ion. Include the electrical charges of the ions. aluminium atom aluminium ion oxygen atom oxide ion Fig. 9.2 [4] (ii) Describe what happens to each aluminium ion on the surface of the cathode during electrolysis. [2] (iii) The symbolic equation below shows the overall chemical change during the electrolysis of aluminium oxide. Complete the balancing of the equation. Al2O3 4Al + O2 [1]

18 © UCLES 2006 0653/03/O/N/06 For Examiner's Use 10 (a) Explain in terms of particles why, when a gas is compressed, the pressure exerted by the gas on the container increases as its volume decreases. [2] (b) Explain the difference between speed and velocity. [1] (c) Explain why a source of alpha radiation is more dangerous if it gets inside the human body than outside the body. [2]

19 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. 0653/03/O/N/06 [Turn over BLANK PAGE

20 © UCLES 2006 0653/03/O/N/06 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 AAluminium 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 Sulphur 16 35.5 CChlorine 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 TThallium 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 2006 question paper 0653 COMBINED SCIENCE 0653/03 Paper 3 (Extended Theory), maximum raw mark 80 This mark scheme is published as an aid to teachers and students, 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. All Examiners are instructed that alternative correct answers and unexpected approaches in candidates’ scripts must be given marks that fairly reflect the relevant knowledge and skills demonstrated. Mark schemes must be read in conjunction with the question papers and the report on the examination. The grade thresholds for various grades are published in the report on the examination for most IGCSE, GCE Advanced Level and Advanced Subsidiary Level syllabuses. • CIE will not enter into discussions or correspondence in connection with these mark schemes. CIE is publishing the mark schemes for the October/November 2006 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 Syllabus Paper IGCSE - OCT/NOV 2006 0653 3 © UCLES 2006 1 (a) (i) peat / wood / straw / biomass / rubbish / biogas / biodiesel / hydrogen; [1] (ii) 68% (40 + 25 + 3); [1] (b) (i) to reduce energy losses; allow ‘heat loss’ ignore ‘power loss’ [1] (ii) transformers use a.c./cannot use d.c./so voltage can be stepped up (or down); alternating current produces changing magnetic field; [2] (iii) sine wave centred on 0V; amplitude and wavelength approximately steady; [2] [Total 7]

Page 3 Mark Scheme Syllabus Paper IGCSE - OCT/NOV 2006 0653 3 © UCLES 2006 2 (a) A oviduct / Fallopian tube B amniotic fluid C cervix D umbilical cord one mark for any two correct; [2] (b) through the placenta; from its mother’s blood; by diffusion; along umbilical cord; [max 3] (c) forms bond between mother and baby; breast milk contains antibodies; avoids possibility of bacterial contamination; (not ‘clean’ or ‘pure’) at right temperature; changes composition as baby grows; [max 2] (d) virus / HIV, passed from mother to baby; crosses the placenta / passes from mother’s blood to baby’s blood; [2] [Total 9]

Page 4 Mark Scheme Syllabus Paper IGCSE - OCT/NOV 2006 0653 3 © UCLES 2006 3 (a) (i) 1 carbon dioxide; 2 hydrogen; 3 carbon dioxide; [3] (ii) HNO3; (not ‘NHO3’) [1] (iii) nitric acid; [1] (b) (i) experiment 6; (in 6) time to collect same volume of gas was the shortest / greatest volume in a given time; [2] (ii) (assume in experiment 6 [v.v. if describing experiment 5]) temperature could have been higher; particles (moving faster) colliding more frequently (with the solid) / collisions have more energy; OR acid concentration could have been higher; more acid particles so greater collision frequency; OR greater surface area of solid; so greater collision frequency (between solid and acid particles); [max 2] [Total 9]

Page 5 Mark Scheme Syllabus Paper IGCSE - OCT/NOV 2006 0653 3 © UCLES 2006 4 (a) (i) 4.5V; [1] (ii) 4.5V; [1] (b) (i) A point at which the whole mass may be considered to act; [1] (ii) diagram showing torch on end B and position of M; centre of mass is closer to base; base has larger area; sensible tipping diagram / [max 2] [Total 5]

Page 6 Mark Scheme Syllabus Paper IGCSE - OCT/NOV 2006 0653 3 © UCLES 2006 5 (a) (i) transported, in blood / to muscles; respiration; oxygen combined with glucose; to form water and carbon dioxide; [max 3] (ii) 20 kJ (dm-3); [1] (b) (i) 0.3 (kJ per metre); [1] (ii) the longer the race, the less energy used (per metre); run faster in shorter race / higher proportion of run is acceleration in shorter race; there are other possible answers [2] (c) oxygen debt; he had been respiring anaerobically; producing lactic acid; which must now be broken down using oxygen; (allow marks for good description of carbon dioxide build-up and how this increases breathing rate) [max 3] [Total 10]

Page 7 Mark Scheme Syllabus Paper IGCSE - OCT/NOV 2006 0653 3 © UCLES 2006 6 (a) (i) fractional distillation / fractionation; [1] (ii) F; [1] (b) (i) (1 x 2) + (1 x 16) / 18; [1] (ii) (44 + 36) / 80g products / 32 000 is 2000 times 16 / other working; 2000 x 80 / 160 000g; [2] (c) (i) methane / oxygen; [1] (ii) idea that energy released is greater than energy absorbed; [1] (d) ethene molecules join (allow on diagram); into a long chain (or diagram clearly implies this); reference to how double bonds open to allow the linkage; [max 2] [Total 9]

Page 8 Mark Scheme Syllabus Paper IGCSE - OCT/NOV 2006 0653 3 © UCLES 2006 7 (a) (i) series of straight lines + rays reflecting off walls of fibre, at approx correct angles; [1] (ii) idea of interference / distortion / confusion in what is seen; [1] (iii) less interference / clearer information / more messages can be sent at the same time / signal needs boosting less often; [1] (b) (i) speed = distance / time = 1000 / 3; = 333 m/s; [2] (ii) measure mass with, scales / balance; measure volume; displacement method for measuring volume described; density = mass / volume; [4] [Total 9]

Page 9 Mark Scheme Syllabus Paper IGCSE - OCT/NOV 2006 0653 3 © UCLES 2006 8 (a) (i) phloem tubes are near surface (of stem); [1] (ii) phloem contains substances the plant has made; sugar / sucrose / amino acids; not glucose,. not starch xylem contains (mostly) water; [max 2] (b) (i) reach all parts of the plant (so kill all feeding insects); only kill insects that eat the plant / do not kill beneficial insects; need to use less; not washed away (by rain); [max 2] (ii) biological; [1] (c) a group of cells; similar to each other / carrying out the same function; [max 2] [Total 8]

Page 10 Mark Scheme Syllabus Paper IGCSE - OCT/NOV 2006 0653 3 © UCLES 2006 9 (a) can be hammered into different shapes M poor conductor of heat is a gas at room temperature (20°C) good conductor of electricity M poor conductor of electricity both required for one mark; [1] (b) 13; [1] (c) (i) aluminium ion electron config. 2.8; charge 3+; oxide ion electron config. 2.8; charge 2-; [4] (ii) gains electrons / is discharged / becomes an (aluminium) atom; (each ion gains) three electrons; [2] (iii) 2Al2O3 → 4Al + 3O2; [1] [Total 9]

Page 11 Mark Scheme Syllabus Paper IGCSE - OCT/NOV 2006 0653 3 © UCLES 2006 10 (a) particles collide, more often / harder / faster; with container walls; [2] (b) speed is a scalar quantity / velocity is vector quantity; OR velocity specifies direction but speed does not; [1] (c) alpha will be absorbed by, air / skin, from outside; damage cells within the body / mutation / damage DNA / cause cancer; not ‘ionises cells’ [2] [Total 5]