Cambridge IGCSE Science - Combined 0653 — 2012 May/June Paper 3 · Variant 1

This document consists of 23 printed pages and 1 blank page. IB12 06_0653_31/4RP © UCLES 2012 [Turn over *3991318441* For Examiner's Use 1 2 3 4 5 6 7 8 9 Total UNIVERSITY OF CAMBRIDGE INTERNATIONAL EXAMINATIONS International General Certificate of Secondary Education COMBINED SCIENCE 0653/31 Paper 3 (Extended) May/June 2012 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. DO NOT WRITE IN ANY BARCODES. Answer all questions. A copy of the Periodic Table is printed on page 24. 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 2012 0653/31/M/J/12 For Examiner's Use 1 Sugar cane is a food crop grown in Australia. It is harvested and then transported on small trains to the processing plant. Fig. 1.1 shows one of the trains carrying sugar cane. Fig. 1.1 (a) The mass of the engine and empty trucks is 20 000 kg and the mass of the sugar cane transported is 10 000 kg. The train travels at a speed of 0.5 m / s. (i) Calculate the kinetic energy of the loaded train. State the formula that you use and show your working. formula used working [2] (ii) To travel at this speed, a driving force of 1 000 000 N is needed. Calculate the work done by the engine of the train when it travels 1 km. State the formula that you use and show your working. formula used working [2]

3 © UCLES 2012 0653/31/M/J/12 [Turn over For Examiner's Use (iii) It takes the train 5 minutes to travel 1 km. Calculate the power output of the engine. State the formula that you use and show your working. formula used working [2] (b) The track for the train is composed of short lengths of steel rail with small gaps left between them as shown in Fig. 1.2. gap steel rail Fig. 1.2 Suggest a reason for leaving these small gaps. [2]

4 © UCLES 2012 0653/31/M/J/12 For Examiner's Use 2 An element is a substance that is made of atoms which have the same proton number. Most atoms contain protons, neutrons and electrons. (a) Name the element whose atoms do not usually contain any neutrons. [1] (b) The electronic structures (configurations) of atoms of three elements, P, Q and R are shown below. P 2,8,1 Q 2,8 R 2,7 (i) Use the electronic structures to state and explain the group numbers in the Periodic Table that contain elements P, Q and R. P Group Q Group R Group explanation [2] (ii) State and explain which of the elements, P, Q or R, is the least reactive. element explanation [1] (iii) State and explain which one of the elements, P, Q or R, is a good conductor of electricity. element explanation [1]

5 © UCLES 2012 0653/31/M/J/12 [Turn over For Examiner's Use (c) Most metallic elements occur combined with non-metals in the Earth’s crust. For thousands of years, humans have carried out chemical reactions to extract metals from their ores. Fig. 2.1 shows a cross-section through a shaft furnace which was a simple reaction vessel used by ancient civilisations to extract iron. waste gases escape air outer wall made of clay iron formed inside the furnace mixture of raw materials Fig. 2.1 In this shaft furnace the mixture of raw materials consisted of charcoal and iron ore. Charcoal contains mainly carbon, and iron ore contains iron oxide. Nowadays iron is extracted from iron ore in a blast furnace. (i) Name another raw material, which is added to a modern blast furnace but which is not present in the shaft furnace in Fig. 2.1. Explain briefly why this material is used. name of material reason this material is used [2] (ii) Iron is extracted from iron ore when a gaseous oxide of carbon reacts with iron oxide. Write a word chemical equation for this reaction. [2]

6 © UCLES 2012 0653/31/M/J/12 For Examiner's Use (d) (i) Suggest, in terms of relative reactivity, why a mixture of aluminium oxide and carbon does not produce any metallic aluminium in a blast furnace. [2] (ii) Name the process that is used to extract aluminium from aluminium oxide. [1]

7 © UCLES 2012 0653/31/M/J/12 [Turn over For Examiner's Use 3 Marmots are herbivorous mammals. Fig. 3.1 shows a marmot. Fig. 3.1 A study has been carried out into the marmots living in Colorado, USA. The winters in this part of Colorado are so cold that the marmots would not be able to find enough food to eat. Instead, they allow their body temperature to drop much lower than normal and stay inactive for many months. This is called hibernation. They do not eat while they are hibernating. They emerge from hibernation in spring. (a) Before they hibernate, marmots build up large fat stores beneath their skin. Suggest and explain what marmots must do in order to build up large fat stores in their bodies. [2]

8 © UCLES 2012 0653/31/M/J/12 For Examiner's Use (b) Fig. 3.2 shows the percentage of marmots with different body masses that survive through the winter. 100 80 60 40 percentage of marmots surviving body mass / kg 2 3 4 5 Fig. 3.2 (i) Describe the relationship between a marmot's body mass and its chance of surviving the winter. [2] (ii) Suggest how a layer of fat beneath the skin can reduce heat transfer from a hibernating marmot's body to its surroundings. [1] (c) In the last twenty years, spring has been arriving earlier in the year in Colorado. This is a result of global warming. Explain how human activities, other than the combustion of fossil fuels, are thought to contribute to global warming. [3]

9 © UCLES 2012 0653/31/M/J/12 [Turn over For Examiner's Use (d) Fig. 3.3 shows the mean body mass of the marmots on the first day of August (during summer) between 1976 and 2006. 3.5 3.0 2.5 2.0 mean body mass / kg 1976 1986 1996 2006 Fig. 3.3 (i) Describe the general trend shown in Fig. 3.3. [1] (ii) Suggest how the earlier arrival of spring could be responsible for this trend. [1]

10 © UCLES 2012 0653/31/M/J/12 For Examiner's Use 4 Fig. 4.1 shows the apparatus a student used to investigate the effect of changing the acid concentration on the rate of reaction between excess dilute hydrochloric acid and magnesium. At the start of the experiment the measuring cylinder contained no gas and was full of water. water measuring cylinder dilute hydrochloric acid bung magnesium gas side-arm test-tube Fig. 4.1 To carry out his investigation the student used the following method. • He dropped the magnesium into the dilute acid. • He immediately placed the bung into the side-arm test-tube and started a stopclock. • He measured the volume of gas in the measuring cylinder every half minute, for eight minutes. He carried out two experiments, A and B, in which the only variable that he changed was the concentration of the hydrochloric acid. (a) State two other variables that the student needed to keep the same in experiments A and B. 1 2 [1]

11 © UCLES 2012 0653/31/M/J/12 [Turn over For Examiner's Use (b) Fig. 4.2 shows the results the student obtained for experiments A and B. experiment experiment A experiment experiment B 0 1 2 3 4 5 6 7 8 9 45 40 35 30 25 20 15 10 5 0 time / minutes volume of gas collected / cm3 experiment A experiment B Fig. 4.2 (i) In which experiment, A or B, did the student use hydrochloric acid which had the higher concentration? Explain your answer. experiment explanation [1]

12 © UCLES 2012 0653/31/M/J/12 For Examiner's Use (ii) The student was told that he could calculate the average rate of reaction using: maximum volume of gas collected minimum time taken to collect maximum volume average rate of reaction = Use the information in Fig. 4.2 to calculate the average rate of reaction for experiment A. Show your working and state the units. [3] (c) The balanced symbolic equation for the reaction between hydrochloric acid and magnesium is shown below. Mg (s) + 2HCl (aq) MgCl2 (aq) + H2 (g) (i) What is meant by the state symbol (aq) in this equation? [1] (ii) Suggest why the reaction in both experiments A and B above produced the same volume of gas. [2]

13 © UCLES 2012 0653/31/M/J/12 [Turn over BLANK PAGE Please turn over for Question 5.

14 © UCLES 2012 0653/31/M/J/12 For Examiner's Use 5 (a) A bat produces a sound wave with a frequency of 212 kHz and a wavelength of 0.0016 m. (i) This sound is outside the audible frequency range for humans. State the approximate audible frequency range for humans. [1] (ii) State the meaning of the terms frequency and wavelength, when describing a wave. You may use a diagram if it helps your explanation. frequency wavelength [2] (iii) Calculate the speed of the sound wave produced by the bat. State the formula that you use and show your working. formula used working [2]

15 © UCLES 2012 0653/31/M/J/12 [Turn over For Examiner's Use (iv) Sound travels through the air by a series of compressions and rarefactions. Describe what this means in terms of air particles. [2] (b) A girl shouts and waves to another girl in the school playground as shown in Fig. 5.1. Fig. 5.1 The sound energy and the light energy both travel from one girl to the other by wave motion. (i) State whether sound waves and light waves are transverse or longitudinal. Sound waves are . Light waves are . [2] (ii) The girls could have communicated with each other using their mobile phones (cell phones). Name the type of electromagnetic wave used to communicate between mobile phones. [1]

16 © UCLES 2012 0653/31/M/J/12 For Examiner's Use 6 Fig. 6.1 shows part of a section across a root from a radish plant, photographed through a microscope. Fig. 6.1 (a) On Fig. 6.1, use a label line to label a root hair cell. [1] (b) Root hair cells absorb water from the soil. (i) State one other function of root hair cells. [1] (ii) Explain how root hair cells are adapted for their functions. [2]

17 © UCLES 2012 0653/31/M/J/12 [Turn over For Examiner's Use (c) A complete radish plant was placed with the lower part of the root standing in water. A soluble red dye was added to the water. After a while, the veins in the leaves of the radish plant became red. (i) Name the tissue in the radish plant through which the coloured water was transported from the roots to the leaves. [1] (ii) On Fig. 6.1, write the letter A to show the position of this tissue in the root. [1] (iii) Water was drawn up through the radish plant because water vapour was constantly escaping from its leaves. A plastic bag was placed over the leaves of the radish plant, and the water vapour formed colourless droplets of liquid water on the bag as it condensed. Explain why these water droplets were not red. [2]

18 © UCLES 2012 0653/31/M/J/12 For Examiner's Use 7 (a) (i) Draw a circuit diagram that a student could use to investigate how the change in potential difference across a lamp affects the current flowing through it. [3] (ii) During his investigations, the student measured the voltage across the lamp as 3.0 V and the current passing through the lamp as 0.3 A. Calculate the resistance of the lamp. State the formula that you use and show your working. formula used working [2]

19 © UCLES 2012 0653/31/M/J/12 [Turn over For Examiner's Use (b) Table 7.1 shows some information about six pieces of wire, all at room temperature (20 °C). Table 7.1 wire metal composition length / cm cross-sectional area / mm2 A copper 10 0.5 B nichrome 10 0.5 C copper 20 0.5 D nichrome 20 0.5 E copper 10 1.0 F copper 20 1.0 (i) Which wire, B or D, will have the greater resistance? Explain your answer. wire [1] (ii) Which wire, A or E, will have the greater resistance? Explain your answer. wire [1] (c) A plastic rod is rubbed with a cloth. The rod becomes charged. There are two types of electric charge. (i) State the names of these charges. 1 2 [1] (ii) Charged particles are transferred between the rod and cloth. Name the charged particles transferred. [1]

20 © UCLES 2012 0653/31/M/J/12 For Examiner's Use 8 Hydrocarbons are compounds that contain carbon and hydrogen only. The hydrocarbon that contains the simplest molecules is methane. (a) (i) The diagrams below show an atom of carbon and an atom of hydrogen. H C Complete the covalent bonding diagram of a molecule of methane to show how the bonding electrons are arranged. [2] (ii) Complete the molecular structure diagrams below to show molecules of the hydrocarbons ethane and ethene. ethane C H ethene C H [2]

21 © UCLES 2012 0653/31/M/J/12 [Turn over For Examiner's Use (b) In many countries, ethanol, C2H6O , is added to hydrocarbon fuels such as gasoline. The products of complete combustion of ethanol are the same as those of hydrocarbons such as methane. Suggest the word chemical equation for the complete combustion of ethanol. [2]

22 © UCLES 2012 0653/31/M/J/12 For Examiner's Use 9 (a) Define the term hormone. [3] (b) Adrenaline is sometimes called the 'fright, flight or fight' hormone. It is produced when a person is frightened. One effect of adrenaline is to increase a person's pulse rate. Explain how this could help a person to run away from the thing that has frightened them. [2] (c) Plants also produce hormones. One plant hormone is auxin. Auxin helps plant shoots to respond to light coming from only one direction. (i) State the correct term for the growth response of a plant to light coming from only one direction. [1]

23 Copyright Acknowledgements: Question 6 Photograph © B23WP8 cross section of a radish root; Biodisc/Visuals Unlimited/Alamy. 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 2012 0653/31/M/J/12 For Examiner's Use (ii) Explain how auxin helps a plant shoot respond to light coming from only one direction. You may use a diagram as part of your explanation. [3]

24 © UCLES 2012 0653/31/M/J/12 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 May/June 2012 question paper for the guidance of teachers 0653 COMBINED SCIENCE 0653/31 Paper 3 (Extended 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 must be read in conjunction with the question papers and the report on the examination. • Cambridge will not enter into discussions or correspondence in connection with these mark schemes. Cambridge is publishing the mark schemes for the May/June 2012 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 – May/June 2012 0653 31 © University of Cambridge International Examinations 2012 1 (a) (i) (KE =) ½ mv2 ; = ½ × 30 000 × 0.5 × 0.5 = 3750 J ; [2] (ii) work done = force × distance ; = 1 000 000 × 1000 = 1 000 000 000 J; [2] (iii) power = work ÷ time ; = 1 000 000 000 ÷ 300 = 3 300 000 W / 3 333 333 W ; [2] (b) metal / steel / track expands in summer / hot weather / when temperature increases ; metal can expand into gap ; prevents damage to tracks ; [max 2] [Total: 8] 2 (a) hydrogen ; [1] (b) (i) P Group 1, Q Group 0 (reject 8), R Group 7; (all required) outer electrons determine group number / answer based on identifying the elements and looking up on Periodic Table ; [2] (ii) (Q) it is a noble / inert gas / reference to filled (electron) shells ; [1] (iii) (P) it is a metal ; (reject – it is sodium) [1] (c) (i) limestone / calcium carbonate ; forms slag / removes impurities / removes silicon dioxide ; [2] (ii) iron oxide + carbon monoxide → iron + carbon dioxide ;; [2] [LHS + RHS] (d) (i) aluminium more reactive than carbon ; so carbon unable to bond with oxygen / remove oxygen from aluminium oxide / break bond between aluminium and oxygen / so a displacement reaction does not occur ; [2] (ii) electrolysis ; [1] [Total: 12]

Page 3 Mark Scheme: Teachers’ version Syllabus Paper IGCSE – May/June 2012 0653 31 © University of Cambridge International Examinations 2012 3 (a) eat a lot / eat more ; eat / take in, more energy than they use ; excess, carbohydrate / protein, converted to / stored as fat ; [max 2] (b) (i) the greater the body mass, the greater the chance of survival ; idea that effect is greater at lower body masses / levels off at higher body masses ; use of figures ; [max 2] (ii) poor conductor / conduction / good insulator / insulation ; [1] (c) reference to build-up of carbon dioxide to the atmosphere ; deforestation + explanation ; addition of methane to the atmosphere ; one named source of methane, e.g. paddy field, cattle ; idea that (long wave) radiation is trapped by greenhouse gases ; [max 3] (d) (i) (mean) body mass is increasing ; [1] (ii) marmots have more time to feed (from spring onwards) ; marmots lose less weight during hibernation as winters are shorter ; [max 1] [Total: 10] 4 (a) temperature, surface area of magnesium ; [1] (allow length, mass or size of magnesium (ribbon), do not allow amount of magnesium) (b) (i) (B) reference to higher rate / steeper graph ; [1] (ii) (maximum volume of gas) 40 cm3 and time of reaction 5 minutes / 300 s ; average rate = 40 ÷ 5 = 8 / 40 ÷ 300 = 0.13 ; units (mark separately) cm3 / minute or cm3 / s ; [max 3] (c) (i) aqueous (solution) / dissolved in water / in solution ; [1] (ii) same mass / length / size / amount of magnesium used in both ; acid in excess / all magnesium used up in both ; gas volume depends on amount of magnesium / owtte ; [max 2] [Total: 8]

Page 4 Mark Scheme: Teachers’ version Syllabus Paper IGCSE – May/June 2012 0653 31 © University of Cambridge International Examinations 2012 5 (a) (i) between 10 and 20 Hz to between 20 000 and 25 000 Hz ; [1] (ii) frequency - number of waves produced / passing a point per second ; wavelength - distance between two peaks / troughs on consecutive waves ; [2] (iii) (v =) f × λ ; 212 000 × 0.0016 = 339.2 m / s ; [2] (iv) compression region of high pressure / lots of air particles ; rarefaction region of low pressure / fewer air particles ; [2] (b) (i) sound – longitudinal ; light – transverse ; [2] (ii) microwaves ; [1] [Total: 10] 6 (a) label to root hair cell ; [1] (b) (i) absorb, minerals / ions / salts / named ion ; [1] (ii) large surface area ; so more, water / ions, can be absorbed (at the same time) ; contain, cell sap / cytoplasm, that is more concentrated than water ; [max 2] (c) (i) xylem ; [1] (ii) A in central area of root ; [1] (iii) idea that red dye has mixed with water, not combined with it ; idea that water molecules and dye molecules behave separately / differently ; (only) water evaporates / dye does not evaporate ; other valid point ; [max 2] [Total: 8]

Page 5 Mark Scheme: Teachers’ version Syllabus Paper IGCSE – May/June 2012 0653 31 © University of Cambridge International Examinations 2012 7 (a) (i) ammeter in series with lamp ; voltmeter in parallel with lamp ; means of varying the potential difference across lamp ; [3] (ii) (R =) V / I ; = 3 / 0.3 = 10 Ω ; [2] (b) (i) D its longer / resistance proportional to length ; [1] (ii) A small cross-sectional area / owtte; [1] (c) (i) positive and negative ; [1] (ii) electron ; [1] [Total: 9] 8 (a) (i) at least one shared pair shown ; four shared pairs with no extraneous outer shell electrons ; [2] (ii) ethane H C H H C H H H ethene H C H H C H ;; [2] (b) ethanol + oxygen → carbon dioxide + water ;; [LHS RHS] [2] [Total: 6]

Page 6 Mark Scheme: Teachers’ version Syllabus Paper IGCSE – May/June 2012 0653 31 © University of Cambridge International Examinations 2012 9 (a) chemical / substance ; produced by a gland / endocrine gland ; carried by the blood ; affects specific / target organs ; destroyed by the liver ; [max 3] (b) more, oxygen / glucose, delivered to muscles ; more energy for muscles ; higher respiration rate (in muscles) ; muscles can work harder / faster ; [max 2] (c) (i) (positive) phototropism ; [1] (ii) auxin made in tip (of shoot) ; accumulates on shady side ; makes cells on this side get longer ; so shady side grows faster than lit side ; [3 max] [Total: 9]