Cambridge IGCSE Science - Combined 0653 — 2015 Oct/Nov Paper 2 · Variant 2

This document consists of 24 printed pages. DC (NH/SG) 103608/3 © UCLES 2015 [Turn over * 6 7 5 2 2 5 2 4 4 3 * COMBINED SCIENCE 0653/22 Paper 2 (Core) October/November 2015 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 an HB 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 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. Cambridge International Examinations Cambridge International General Certificate of Secondary Education

2 0653/22/O/N/15 © UCLES 2015 1 Fig. 1.1 shows a van being driven along a flat road at a constant speed. The arrows on the diagram represent the four main forces acting on the van. reaction force driving force force X force Y Fig. 1.1 (a) (i) Use words from the list below to name forces X and Y. Each word may be used once, more than once or not at all. friction kinetic gravity mass pressure weight force X … force Y … [2] (ii) The driving force is 750 N. State the value of force X. Give a reason for your answer. force X = … N reason … …[2]

3 0653/22/O/N/15 © UCLES 2015 [Turn over (b) Fig. 1.2 shows a speed/time graph for the van for two minutes of its journey. 20 10 0 0 30 60 90 120 speed m / s time / s Fig. 1.2 (i) Describe the motion of the van between 1. 30 s and 90 s, … 2. 90 s and 120 s. …[2] (ii) The van is travelling at 20 m/s. Calculate the speed of the van in km/h. Show your working. working speed = … km/h [2]

4 0653/22/O/N/15 © UCLES 2015 2 Petroleum (crude oil) is a mixture of compounds. Some of these compounds are used as fuels. (a) (i) Name the process used to separate the petroleum mixture into useful fractions. …[1] (ii) Explain why this process involves a physical change but not a chemical change. … …[1] (b) Fig. 2.1 shows how petroleum fractions can be separated in the laboratory. thermometer side-arm test-tube petroleum heat cool delivery tube small test-tube fraction A Fig. 2.1 The petroleum is heated until the temperature shown by the thermometer reaches 100 °C. Fraction A collects in the small test-tube. (i) Describe the processes involved in moving substances from the petroleum to the small test-tube. … … …[2]

5 0653/22/O/N/15 © UCLES 2015 [Turn over (ii) The small test-tube used to collect the fraction is replaced with a fresh test-tube. Heating is continued, and three further fractions, B, C, and D, are collected. All four fractions are shown in Fig. 2.2. A B C D Fig. 2.2 The fractions become darker from A to D. The fractions are collected over the temperature ranges shown in Table 2.1. Table 2.1 fraction temperature range / °C A room temperature to 100 B 100 to 150 C 150 to 200 D 200 to 250 Use the information in Table 2.1 to state one trend in the physical properties of the fractions A to D apart from colour. … …[1] (c) Petroleum fractions contain hydrocarbons. Complete the word equation for the complete combustion of a hydrocarbon. + + K\GURFDUERQ [2]

6 0653/22/O/N/15 © UCLES 2015 3 (a) Use lines to connect the boxes on the left with the correct boxes on the right. Use each description once only. One line has been drawn for you. chemical description fats can be joined together to make starch or glycogen glycogen turns purple with the biuret test protein made from fatty acids and glycerol sugars storage carbohydrate not found in plants [2] (b) Table 3.1 gives some information about the nutrients contained in 100 cm3 of three different types of milk. Table 3.1 nutrient milk A milk B milk C protein / g 3.4 3.6 3.6 carbohydrate / g 4.7 4.8 4.9 fat / g 3.6 2.4 0.1 calcium / mg 122 124 129 Energy can be released in cells from the carbohydrate, fat and protein in the milk. (i) Name the process by which energy is released in cells. …[1] (ii) Explain why milk A would be the best choice of milk for an athlete. … … …[2]

7 0653/22/O/N/15 © UCLES 2015 [Turn over (iii) The RDA (recommended daily allowance) for calcium is 900 mg per day for most adults. Calculate the volume of milk C needed to provide the recommended daily allowance of calcium. Show your working. volume = … cm3 [2] (iv) Suggest one group of adults who should take in more than the normal RDA of calcium in their diet. Explain your answer. group of adults … explanation … …[2]

8 0653/22/O/N/15 © UCLES 2015 4 Fig. 4.1 shows an electric fan heater used to keep people warm. cooler air in warmer air out Fig. 4.1 Fig. 4.2 shows the circuit symbols for an electric heater, and for an electric motor to drive the fan. M electric heater electric motor Fig. 4.2 Fig. 4.3 shows part of the circuit diagram for the fan heater. mains electricity supply M Fig. 4.3 (a) On Fig. 4.3 complete the circuit diagram using the correct symbols for • an on-off switch to control the electricity supply to the fan heater, • a fuse to protect the circuit against electrical overload. [3]

9 0653/22/O/N/15 © UCLES 2015 [Turn over (b) Another type of switch is also needed in the circuit as a safety device to cut off the heater if the temperature rises too much. This is called a thermal cut-out. The thermal cut-out must switch off the heater but not the fan. The fan must continue to operate to reduce the temperature. Fig. 4.4 shows the structure of this switch. contacts bimetallic strip iron brass Fig. 4.4 (i) On Fig. 4.3 in (a), mark with an X a point in your completed circuit where this switch could be put into the circuit to switch off the heater but not the fan. [1] (ii) Use words from the list to complete the description of how the thermal cut-out operates to switch off the heater. Each word may be used once, more than once or not at all. bend broken contract cooled heated made magnetised stretch When metals are …, they expand. Brass expands more than iron. This causes the bimetallic strip to … . The contacts are … by this change. [3] (iii) Suggest a suitable position inside the fan heater to place the thermal cut-out so that it responds to the temperature in the room, not to the temperature of the heater. Give a reason for your answer. … … …[2]

10 0653/22/O/N/15 © UCLES 2015 5 Table 5.1 shows some elements placed in order of reactivity. Table 5.1 most reactive potassium sodium calcium magnesium zinc iron hydrogen least reactive copper (a) Table 5.2 shows the reactions of some of the elements when added to dilute hydrochloric acid. Table 5.2 element added to acid observation calcium bubbles of hydrogen given off quickly zinc copper no reaction (i) Complete Table 5.2 by adding the observation you would expect when zinc is added to the acid. [1] (ii) Explain your answer to (a)(i) by referring to the reactivity series. … … …[2]

11 0653/22/O/N/15 © UCLES 2015 [Turn over (b) Sodium and potassium are in Group I of the Periodic Table. (i) Describe the trend in reactivity down Group I. …[1] (ii) The reactivities of sodium and potassium can be compared by placing a piece of each element into water. Fig. 5.1 shows a piece of sodium being placed into water. sodium water tongs Fig. 5.1 Describe two similarities and one difference observed between this reaction and the reaction when potassium is placed into water. similarity 1 … similarity 2 … difference …[3]

12 0653/22/O/N/15 © UCLES 2015 6 (a) Fig. 6.1 shows a female aphid and some of her offspring. The aphid can reproduce both sexually and asexually. adult female aphid offspring A B C D E F G H Fig. 6.1 (i) Only offspring C and H were produced asexually. State how the information in Fig. 6.1 supports this. … …[1] (ii) Describe how the genetic information in the cells of offspring C and H compares with that of the adult female. … …[1]

13 0653/22/O/N/15 © UCLES 2015 [Turn over (iii) Describe how the genetic information in the cells of offspring A compares with that of the adult female and with that of the rest of the offspring. … … …[2] (b) The aphid feeds on young shoots of plants by putting its sharp mouthparts into stems. It obtains dissolved food substances which are being transported through the plant. (i) Suggest which plant tissue the aphid reaches with its mouthparts. Explain your answer. … …[2] (ii) Fig. 6.2 shows a cross-section of the stem of a plant. Fig. 6.2 On Fig. 6.2, shade in one area where you would find the tissue that transports dissolved food substances. [1]

14 0653/22/O/N/15 © UCLES 2015 (c) The shoots of the plants make their food by photosynthesis. (i) Complete the word equation for photosynthesis. carbon dioxide + … sugar + … [1] (ii) The plant shown in Fig. 6.3 has all the necessary conditions for photosynthesis. Fig. 6.3 Give two environmental conditions needed for photosynthesis. 1 … 2 …[2] (d) A student took a leaf from the plant shown in Fig. 6.3. He made a drawing of the leaf. His drawing is shown in Fig. 6.4. green areas white areas Fig. 6.4 He then tested the leaf for starch. (i) Predict the results of the starch test on this leaf in the different areas. green areas … white areas …[1] (ii) Explain the reason for your predictions in part (d)(i). … …[1]

15 0653/22/O/N/15 © UCLES 2015 [Turn over Please turn over for Question 7.

16 0653/22/O/N/15 © UCLES 2015 7 (a) A motorcyclist needs to see other vehicles and pedestrians. Fig. 7.1 shows a motorcyclist from above and a taxi some distance behind him. The motorcyclist looks in his rear view mirror to see the taxi. rear view mirror Fig. 7.1 (i) Fig. 7.2 shows how a ray of light travels from the taxi to the mirror, then to the motorcyclist so he can see the taxi behind. mirror eye car Fig. 7.2 The ray strikes the mirror at an angle of 30° to the normal. On Fig. 7.2 1. draw the normal to the mirror at the point the ray hits the mirror, 2. write in the value of the angle of reflection. [2]

17 0653/22/O/N/15 © UCLES 2015 [Turn over (ii) Fig. 7.3 shows the view in the mirror seen by the motorcyclist. Fig. 7.3 Explain why the word on the taxi behind is seen the wrong way round. … …[1] (b) The motorcyclist follows directions to his destination using his satellite navigation system (Satnav). The Satnav uses signals from satellites orbiting the Earth to show the position of the motorcycle on a map displayed on the Satnav screen in front of him. State the type of electromagnetic wave used by satellites sending signals to Earth. …[1] (c) The motorcyclist is travelling at night along a street. The street is lit by lamps which emit yellow light. (i) Fig. 7.4 shows a graph of a yellow light wave. On Fig. 7.4 draw a labelled arrow to indicate the amplitude of this light wave. [1] Fig. 7.4 (ii) The amplitude of a light wave determines the brightness of the light. State the property of sound determined by the amplitude of a sound wave. …[1]

18 0653/22/O/N/15 © UCLES 2015 (d) The motorcyclist stops in a long narrow street with a tall building at one end. He sounds his horn and hears an echo from the tall building 2 seconds later. The speed of sound in air is 330 m/s. Calculate the distance of the motorcyclist from the building when he sounds his horn. State any formula that you use and show your working. formula working distance = … m [2] (e) At the end of his journey, the motorcyclist enters the tall building and walks over carpeted floors before arriving at a door. When he touches the metal door handle, he gets a mild electric shock! Explain why the motorcyclist has become electrically charged and then receives a shock when he touches the door handle. … … … …[2]

19 0653/22/O/N/15 © UCLES 2015 [Turn over Please turn over for Question 8.

20 0653/22/O/N/15 © UCLES 2015 8 (a) Atoms are made up of three types of particle. The three particles are listed below. electrons neutrons protons Complete the following sentences using the names of the three particles. Each name may be used once, more than once, or not at all. … and … have the same mass, but … have much smaller mass. … and … have opposite charges but … have no charge. [2] (b) The proton number of a chlorine atom is 17. (i) State the number of electrons in a chlorine atom. Explain your answer. … …[1] (ii) The nucleon number of a chlorine atom is 35. State the number of neutrons in this chlorine atom. Explain your answer. … …[1] (iii) A copy of the Periodic Table is printed on page 24. State how the position of chlorine in the Periodic Table shows that it is a non-metal. … …[1]

21 0653/22/O/N/15 © UCLES 2015 [Turn over (c) Hydrogen and chlorine react to form hydrogen chloride gas. In this reaction a chlorine atom forms a covalent bond with a hydrogen atom to make a hydrogen chloride molecule. (i) State what is meant by a covalent bond. … …[1] (ii) State why hydrogen and chlorine form a covalent bond rather than an ionic bond. … …[1] (d) Fig. 8.1 shows apparatus used to dissolve hydrogen chloride gas in water to form hydrochloric acid. hydrogen chloride funnel water with indicator Fig. 8.1 The water contains full-range indicator (Universal Indicator) added before the hydrogen chloride dissolves. (i) State the colour of the indicator in pure water. … [1] (ii) The indicator turns red. Suggest the change in pH. from pH … to pH … [1]

22 0653/22/O/N/15 © UCLES 2015 (e) An old copper coin has corroded and become coated with a green layer of copper carbonate. Fig. 8.2 shows a corroded copper coin being cleaned in dilute hydrochloric acid. green layer bubbles of gas dilute hydrochloric acid Fig. 8.2 The acid reacts with the green layer to form a blue solution. The word equation for the reaction between an acid and a carbonate is shown below. + + + DFLG FDUERQDWH ; ZDWHU JDV< (i) What type of compound is X? … [1] (ii) Name gas Y. Describe a test for it. name of gas … test … … result …[3]

23 0653/22/O/N/15 © UCLES 2015 9 (a) Fig. 9.1 shows part of a simple food chain in a field of wheat. wheat seeds mouse grass snake Fig. 9.1 (i) Define the term food chain. … … …[2] (ii) A badger also lives in the habitat. The badger eats all of the organisms in the food chain. The badger and these organisms form a food web. Complete Fig. 9.2 to show the food web. wheat seeds mouse grass snake Fig. 9.2 [2] (b) The wheat is harvested. Suggest one possible way in which the mice respond to the removal of their food supply. … …[1]

24 0653/22/O/N/15 © UCLES 2015 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.). To avoid the issue of disclosure of answer-related information to candidates, all copyright acknowledgements are reproduced online in the Cambridge International Examinations Copyright Acknowledgements Booklet. This is produced for each series of examinations and is freely available to download at www.cie.org.uk after the live examination series.

® 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 2015 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 2015 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 2015 0653 22 © Cambridge International Examinations 2015 1 (a) (i) force X = friction (force) ; force Y = weight ; [2] (ii) 750 N ; for constant speed, forces must be balanced / owtte ; [2] (b) (i) (30–90 s) constant speed ; (90–120 s) (negative) acceleration / deceleration ; [2] (ii) 20 m / s = 20 × 3 600 m / h ; = 72 000 m / h = 72 (km / h) ; [2] [Total: 8] 2 (a) (i) fractional distillation ; [1] (ii) because new substances are not made ; [1] (b) (i) petroleum fraction boils and vapour moves into delivery tube ; vapour condenses in delivery tube ; [2] (ii) increasing boiling point from A to D ; [1] (c) (hydrocarbon) + oxygen ; water + carbon dioxide ; [2] [Total: 7] 3 (a) chemical description fats can be joined together to make starch or glycogen glycogen turns purple with the biuret test protein made from fatty acids and glycerol sugars storage carbohydrate not found in plants ;; (3 correct for 2 marks, 2 or 1 correct for 1 mark) [2]

Page 3 Mark Scheme Syllabus Paper Cambridge IGCSE – October/November 2015 0653 22 © Cambridge International Examinations 2015 (b) (i) respiration ; [1] (ii) (milk A) it contains the highest total of fat, carbohydrate and protein ; (athlete) would need most energy / it releases most energy ; for (contraction of) muscles ; [max 2] (iii) 129 900 (= 6.97(8)) ; × 100 = 697.6 or 698 (cm3) ; [2] (iv) pregnant women ; extra calcium needed for bones of fetus ; AVP e.g. osteoporosis in older women ; [max 2] [Total: 9] 4 (a) complete circuit with no ‘dead ends’ or short circuits ; on-off switch in main circuit using correct symbol ; fuse in main circuit using correct symbol ; [3] (b) (i) X marked in the heater branch, either side of heater ; [1] (ii) heated ; bend ; broken ; [3] (iii) in the air coming into the heater (owtte) ; senses / switches off when air temperature in room is too high / so it can check room temperature ; [2] [Total: 9]

Page 4 Mark Scheme Syllabus Paper Cambridge IGCSE – October/November 2015 0653 22 © Cambridge International Examinations 2015 5 (a) (i) bubbles (gently) / owtte ; [1] (ii) zinc is above hydrogen in the reactivity series ; zinc is below calcium in the reactivity series ; zinc is above copper in the reactivity series ; [max 2] (b) (i) Increases ; [1] (ii) any two from: melts ; moves / floats ; bubbles ; dissolves / disappears ; and more vigorous / flame / explodes ; [3] [Total: 7] 6 (a) (i) identical (with female adult aphid) ; [1] (ii) (the genetic information) will be identical ; [1] (iii) (the genetic information is) different from the adult female ; (the genetic information is) different from each other ; [2] (b) (i) phloem ; because it transports dissolved food substances around the plant ; [2] (ii) one area of phloem correctly shaded ; [1] (c) (i) (carbon dioxide) + water → (sugar) + oxygen ; [1] (ii) enough light ; (source of) carbon dioxide ; [2] (d) (i) the starch / blue-black colour is only found in the green areas ; [1] (ii) because chlorophyll is needed for photosynthesis ; green areas contain chlorophyll ; starch is produced in the green areas ; [max 1] [Total: 12]

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Page 6 Mark Scheme Syllabus Paper Cambridge IGCSE – October/November 2015 0653 22 © Cambridge International Examinations 2015 (d) (i) green ; [1] (ii) 7 to any less than 4 ; [1] (e) (i) (a) salt ; [1] (ii) carbon dioxide ; limewater ; milky / cloudy ; [3] [Total: 10] 9 (a) (i) a chart / diagram showing the flow of energy ; from organism to organism ; [2] (ii) badger connected to all three organisms ; arrows point in the correct direction ; [2] (b) use an alternative source of food ; move to a different habitat ; [1] [Total: 5]