Cambridge IGCSE Science - Combined 0653 — 2016 May/June Paper 3 · Variant 3

This document consists of 20 printed pages. DC (KN/JG) 116215/3 © UCLES 2016 [Turn over Cambridge International Examinations Cambridge International General Certificate of Secondary Education * 9 5 4 6 5 1 6 1 6 5 * COMBINED SCIENCE 0653/33 Paper 3 (Extended) May/June 2016 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 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 0653/33/M/J/16 © UCLES 2016 1 Paper chromatography can be used to separate and identify a compound in a mixture of compounds. A compound consists of one or more elements that are chemically combined. (a) (i) Define the term mixture. … … … … [2] (ii) A student uses paper chromatography to find out which compounds a mixture Y contains. Fig. 1.1 shows the chromatogram of the student’s results. Y A B C D Fig. 1.1 Deduce which of the compounds A, B, C and D the mixture Y contains. Explain your answer. … … … …[2]

3 0653/33/M/J/16 © UCLES 2016 [Turn over (b) Scientists use chromatography to detect the presence of the compound ethanol in blood. Complete Fig. 1.2 to show the structure of one molecule of ethanol. H C Fig. 1.2 [2] (c) (i) Ethanol is produced when ethene reacts with steam. No other product is made in this reaction. Write the word equation for the reaction of ethene with steam to make ethanol. … [1] (ii) Draw a dot-and-cross diagram to show the bonding in ethene. You only need to show the arrangement of the outer electrons. [2] (iii) Ethane and ethene are both hydrocarbons. Describe a chemical test to distinguish between ethane and ethene. test … … result for ethane … … result for ethene … … [3]

4 0653/33/M/J/16 © UCLES 2016 2 Fig. 2.1 shows an electric circuit. ODPS; ODPS< Fig. 2.1 (a) The potential difference (p.d.) supplied by the battery is 12 V. The p.d. across lamp X is 2 V. Calculate the p.d. across lamp Y. potential difference = … V [1] (b) The current through lamp X is 0.4 A. (i) Calculate the resistance of lamp X. State the formula you use, show your working and state the unit of your answer. formula working resistance = … unit = … [3]

5 0653/33/M/J/16 © UCLES 2016 [Turn over (ii) Calculate the power in the circuit when the current in the circuit is 0.4 A. State the formula you use and show your working. formula working power = … W [2] (iii) Explain why the energy transferred in lamp X is less than the energy transferred in lamp Y. … … … [1] (c) Fig. 2.2 shows a different circuit. ODPS; ODPS< Fig. 2.2 Explain why lights in a house are connected as in the circuit in Fig. 2.2 and not as shown in the circuit in Fig. 2.1. … … … …[2]

6 0653/33/M/J/16 © UCLES 2016 3 The apparatus in Fig. 3.1 is used to investigate the effect of light intensity on the rate of photosynthesis in the aquatic plant Elodea. The intensity of light is varied by changing the distance of the plant from the lamp. The light intensity increases as the distance from the plant decreases. The rate of photosynthesis is measured by counting the number of bubbles of oxygen produced by the plant per minute. ODPS ZDWHU EXEEOHV (ORGHD PHWUHUXOH Fig. 3.1 The results are used to produce the graph shown in Fig. 3.2.          DYHUDJHQXPEHURI EXEEOHVSURGXFHG E\WKHSODQWPLQ OLJKWLQWHQVLW\ DUELWUDU\XQLWV Fig. 3.2 (a) Use data from the graph in Fig. 3.2 to describe the effect of light intensity on the rate of photosynthesis. … … … …[2]

7 0653/33/M/J/16 © UCLES 2016 [Turn over (b) (i) The piece of Elodea is then cut into two pieces of equal size. The experiment is repeated with one of these pieces. On Fig. 3.2 draw a line to suggest how the number of bubbles per minute would change with increasing light intensity when one of these smaller pieces of Elodea is used. [1] (ii) Explain your reasons for the line you drew in (i). … … …[2] (c) Elodea forms part of a food chain in a garden pond. The food chain is shown in Fig. 3.3. Elodea tadpole goldfish heron Fig. 3.3 (i) State all the consumers in this food chain. …[1] (ii) When a goldfish eats a tadpole, most of the chemical energy in the tadpole is lost and does not become part of the goldfish’s body. Describe two reasons for this energy loss. 1. … … 2. … … [2]

8 0653/33/M/J/16 © UCLES 2016 (d) Fig. 3.3 on page 7 shows the following food chain. Elodea tadpole goldfish heron A second food chain in the pond is shown in Fig. 3.4. Elodea water snail goldfish cat Fig. 3.4 In the space below combine the food chains in Fig. 3.3 and Fig. 3.4 to produce a food web. [2]

9 0653/33/M/J/16 © UCLES 2016 [Turn over 4 Fig. 4.1 shows Group I of the Periodic Table of elements. 3 Li lithium 7 11 Na sodium 23 19 K potassium 39 37 Rb rubidium 85 55 Cs caesium 133 87 Fr francium – Fig. 4.1 (a) Deduce the number of electrons in each shell of one atom of sodium. …[1] (b) (i) Sodium reacts vigorously with water to form sodium hydroxide solution and hydrogen gas. Balance the equation below and complete the state symbols. One state symbol has been done for you. Na(s) + H2O( ) → NaOH( ) + H2( ) [2] (ii) Predict what is observed when rubidium reacts with water. … … … …[2] (iii) State one energy transfer that occurs during the reaction between rubidium and water. … energy … energy [1]

10 0653/33/M/J/16 © UCLES 2016 (c) Explain why elements in Group I are more reactive than elements in Group VIII (noble gases). … … … … … …[2] (d) Unpolluted air contains nitrogen, oxygen, noble gases, water vapour and carbon dioxide. (i) Explain how increasing levels of carbon dioxide in the Earth’s atmosphere contribute to global warming. … … … …[1] (ii) Suggest one negative effect of global warming. … …[1]

11 0653/33/M/J/16 © UCLES 2016 [Turn over 5 A man is climbing a mountain. (a) State the form of energy the man has gained at the top of the mountain. …[1] (b) The man makes a loud noise as he climbs. The echo from another mountain 990 m away reaches him 6 seconds later. This is shown in Fig. 5.1. FOLPEHUPDNLQJORXGQRLVH PRXQWDLQ PRXQWDLQ P Fig. 5.1 (not to scale) Use this data to calculate the speed of sound in the air between the two mountains. State the formula you use and show your working. formula working speed = … m / s [2]

12 0653/33/M/J/16 © UCLES 2016 (c) A physics website states that sound is a longitudinal wave with a frequency within the human audible frequency range. (i) Describe one difference between the properties of a longitudinal wave and a transverse wave. … … … …[1] (ii) State the approximate range of human audible frequencies. lowest frequency … Hz highest frequency … Hz [1] (d) On the mountain, the climber sees some ice melting. (i) State the meaning of the term melting point. … … …[1] (ii) Fig. 5.2 shows the arrangement of particles in a solid and a liquid. A B Fig. 5.2 When ice melts it forms liquid water. Describe how diagram B represents the way particles are arranged in water. … … …[2]

13 0653/33/M/J/16 © UCLES 2016 [Turn over (e) On the mountain, the climber is exposed to both infra-red and ultraviolet radiation. Infra-red and ultraviolet radiation are both electromagnetic waves. Infra-red waves travel at a speed of 3 × 108 m / s. State the speed at which ultraviolet waves travel. Explain your answer. speed = … m / s explanation … …[1]

14 0653/33/M/J/16 © UCLES 2016 6 (a) Fig. 6.1 shows an artery and a vein in longitudinal section. artery vein Fig. 6.1 Describe one structural adaptation of each blood vessel for its function. artery … … … vein … … … [3] (b) Complete the following paragraph with the correct terms from the list. You may use each term once, more than once, or not at all. away from blue deoxygenated hepatic vein inside oxygenated pulmonary vein red towards vena cava Veins transport blood … the heart. They usually contain … blood. One vein that contains … blood is the … which transports blood … the lungs. [5]

15 0653/33/M/J/16 © UCLES 2016 [Turn over 7 Electrolysis breaks down ionic compounds into their elements. Fig. 7.1 shows the electrolysis of molten magnesium chloride, MgCl2. d.c. power supply + – electrodes molten magnesium chloride heat Fig. 7.1 (a) Predict the product that forms at the positive electrode (anode). … [1] (b) Magnesium alloys are often used to make car parts because the alloy is strong. (i) Draw a diagram in the box to show the arrangement of atoms in a typical alloy. [2] (ii) Suggest why magnesium alloys are stronger than magnesium metal. … … …[1]

16 0653/33/M/J/16 © UCLES 2016 8 A truck travels at a constant speed for 60 seconds and then slows down. It takes another 40 seconds to come to a stop. Fig. 8.1 shows the speed / time graph for the 100 second journey. 10 0 0 20 40 60 80 100 2 4 6 8 time / s speed m / s Fig. 8.1 (a) Calculate the deceleration of the truck between 60 s and 100 s. Show your working. deceleration = … m / s2 [2] (b) Describe how to use the graph to find the total distance travelled by the truck. … … …[2]

17 0653/33/M/J/16 © UCLES 2016 [Turn over (c) Fig. 8.2 shows the forces on the truck when it is travelling at constant speed. road P Q R S Fig. 8.2 Four forces P, Q, R and S are shown. State which force from P, Q, R and S is 1. the weight of the truck, … 2. the force exerted by the push of the engine. … [1] (d) In modern trucks, computers are used to control the engine. Information is passed between the computer and engine along optical fibres. Light passes through an optical fibre by total internal reflection. Complete Fig. 8.3 to show how a ray of light travels down an optical fibre by total internal reflection. The first angle of incidence (i ) has been labelled for you. i Fig. 8.3 [2] (e) (i) State one use of optical fibres in medicine. … …[1] (ii) Suggest the advantage of using optical fibres for the use stated in (i). … …[1]

18 0653/33/M/J/16 © UCLES 2016 9 (a) Complete the balanced symbol equation for aerobic respiration. … + 6O2 6CO2 + … [1] (b) During aerobic respiration, carbon dioxide is produced which is excreted at the lungs. Fig. 9.1 shows part of the tissue that lines the trachea. to lungs to nose cilia goblet cell (produces mucus) thin layer of mucus Fig. 9.1 (i) Describe how the lungs are protected by the mucus and cilia shown in Fig. 9.1. mucus … … cilia … … [2] (ii) Describe and explain the harmful effect of tobacco smoke on the cilia. … … …[2]

19 0653/33/M/J/16 © UCLES 2016 (c) Fig. 9.2 shows a fetus in the uterus. The fetus cannot breathe inside the uterus, so oxygen is supplied by a different method. placenta liquid X Fig. 9.2 Describe how the placenta supplies the fetus with oxygen. … … …[2] (d) (i) One problem that can occur during pregnancy is the loss of the liquid X shown in Fig. 9.2. Name liquid X. …[1] (ii) Suggest why the loss of liquid X would be harmful to the growing fetus. … …[1]

20 0653/33/M/J/16 © UCLES 2016 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. Group The Periodic Table of Elements 1 H hydrogen 1 2 He helium 4 I II III IV V VI VII VIII 3 Li lithium 7 4 Be beryllium 9 atomic number atomic symbol Key name relative atomic mass 11 Na sodium 23 12 Mg magnesium 24 19 K potassium 39 20 Ca calcium 40 37 Rb rubidium 85 38 Sr strontium 88 55 Cs caesium 133 56 Ba barium 137 87 Fr francium – 88 Ra radium – 5 B boron 11 13 Al aluminium 27 31 Ga gallium 70 49 In indium 115 81 Tl thallium 204 6 C carbon 12 14 Si silicon 28 32 Ge germanium 73 50 Sn tin 119 82 Pb lead 207 22 Ti titanium 48 40 Zr zirconium 91 72 Hf hafnium 178 104 Rf rutherfordium – 23 V vanadium 51 41 Nb niobium 93 73 Ta tantalum 181 105 Db dubnium – 24 Cr chromium 52 42 Mo molybdenum 96 74 W tungsten 184 106 Sg seaborgium – 25 Mn manganese 55 43 Tc technetium – 75 Re rhenium 186 107 Bh bohrium – 26 Fe iron 56 44 Ru ruthenium 101 76 Os osmium 190 108 Hs hassium – 27 Co cobalt 59 45 Rh rhodium 103 77 Ir iridium 192 109 Mt meitnerium – 28 Ni nickel 59 46 Pd palladium 106 78 Pt platinum 195 110 Ds darmstadtium – 29 Cu copper 64 47 Ag silver 108 79 Au gold 197 111 Rg roentgenium – 30 Zn zinc 65 48 Cd cadmium 112 80 Hg mercury 201 112 Cn copernicium – 114 Fl flerovium – 116 Lv livermorium – 7 N nitrogen 14 15 P phosphorus 31 33 As arsenic 75 51 Sb antimony 122 83 Bi bismuth 209 8 O oxygen 16 16 S sulfur 32 34 Se selenium 79 52 Te tellurium 128 84 Po polonium – 9 F fluorine 19 17 Cl chlorine 35.5 35 Br bromine 80 53 I iodine 127 85 At astatine – 10 Ne neon 20 18 Ar argon 40 36 Kr krypton 84 54 Xe xenon 131 86 Rn radon – 21 Sc scandium 45 39 Y yttrium 89 57–71 lanthanoids 89–103 actinoids 57 La lanthanum 139 89 Ac lanthanoids actinoids The volume of one mole of any gas is 24 dm3 at room temperature and pressure (r.t.p.) actinium – 58 Ce cerium 140 90 Th thorium 232 59 Pr praseodymium 141 91 Pa protactinium 231 60 Nd neodymium 144 92 U uranium 238 61 Pm promethium – 93 Np neptunium – 62 Sm samarium 150 94 Pu plutonium – 63 Eu europium 152 95 Am americium – 64 Gd gadolinium 157 96 Cm curium – 65 Tb terbium 159 97 Bk berkelium – 66 Dy dysprosium 163 98 Cf californium – 67 Ho holmium 165 99 Es einsteinium – 68 Er erbium 167 100 Fm fermium – 69 Tm thulium 169 101 Md mendelevium – 70 Yb ytterbium 173 102 No nobelium – 71 Lu lutetium 175 103 Lr lawrencium –

® IGCSE is the registered trademark of Cambridge International Examinations. This document consists of 5 printed pages. © UCLES 2016 [Turn over Cambridge International Examinations Cambridge International General Certificate of Secondary Education COMBINED SCIENCE 0653/33 Paper 3 Extended Theory May/June 2016 MARK SCHEME Maximum Mark: 80 Published 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 May/June 2016 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 – May/June 2016 0653 33 © Cambridge International Examinations 2016 1 (a) (i) contains two (or more) different atoms / substances / elements / compounds ; NOT chemically joined together / NOT chemically combined ; [2] (ii) A C D ; spots from Y match spots in A, C and D / owtte ; [2] (b) O-H bond / –OH shown ; rest of molecule correct ; [2] (c) (i) ethene + water / steam → ethanol ; [1] (ii) double bond shown ; rest of molecule correct ; [2] (iii) bromine (solution) ; (ethane) no reaction / owtte ; (ethene) decolourises bromine ; [3] 2 (a) 10 (V) ; [1] (b) (i) (R =) V / I ; = 2 / 0.4 = 5 ; Ω ; [3] (ii) (P =) VI ; = 12 × 0.4 = 4.8 (W) ; [2] (iii) resistance of Y is greater than resistance of X / pd across Y is greater than pd across X ; [1] (c) all lights get full mains voltage / shone at max brightness ; each light can be switched on / off independently ; if one light fails, the others will still work ; [max 2] 3 (a) as the light intensity increases the rate of photosynthesis increases ; further detail using numbers extracted from the graph e.g. increase in rate declines at 0.06 ; [2] (b) (i) similar shaped line drawn below the existing one ; [1] (ii) fewer bubbles per minute / amount of photosynthesis has decreased ; less chlorophyll / fewer chloroplasts present / fewer leaves / fewer stomata present to release oxygen ; [2] (c) (i) tadpole, goldfish, heron ; [1]

Page 3 Mark Scheme Syllabus Paper Cambridge IGCSE – May/June 2016 0653 33 © Cambridge International Examinations 2016 (ii) goldfish does not eat / digest / absorb all of the tadpole ; energy lost due to respiration / other life process / heat energy lost ; [2] (d) food web correctly drawn with Elodea and goldfish only written once ; arrows in correct direction ; e.g. heron cat goldfish tadpole water snail Elodea [2] 4 (a) 2, 8, 1 [1] (b) (i) 2Na(s) + 2H2O(I) → 2NaOH(aq) + H2(g) ; [2] (ii) rubidium melts ; flame ; gas given off ; temperature increase ; [max 2] (iii) chemical (potential energy) → thermal or heat / light / kinetic (energy) [1] (c) reference to filled outer shell in Group VIII elements ; Group I has 1 electron in outer shell that can be lost ; [max 2] (d) (i) CO2 absorbs heat radiated from Earth’s surface / prevents heat escaping into space ; [1] (ii) extremes of weather / flooding caused by excessive rain or rising sea levels / drought / fires / increasing storm damage to humans or habitats ; [1] 5 (a) (gravitational) potential ; [1] (b) (speed =) distance / time ; = 2 × 990 / 6 = 330 (m / s) ; [2]

Page 4 Mark Scheme Syllabus Paper Cambridge IGCSE – May/June 2016 0653 33 © Cambridge International Examinations 2016 (c) (i) 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 ; longitudinal waves need a medium to travel through ; [max 1] (ii) 20 Hz (allow 10 Hz) and 20 000 Hz (allow 25 000 Hz) ; [1] (d) (i) temperature at which a solid changes state and becomes a liquid ; [1] (ii) particles are randomly arranged ; most particles are touching ; [2] (e) 3 × 10–8 m / s (no mark) all electromagnetic waves travel at the same speed (in vacuo) ; [1] 6 (a) (artery) thick wall ; prevents bursting ; OR contains elastic tissues ; for recoil / smoothing flow of blood ; AND (vein) contain valves to prevent backflow of blood ; [3] (b) towards ; deoxygenated ; oxygenated ; pulmonary vein ; away from ; [5] 7 (a) chlorine (gas) ; [1] (b) (i) at least two different sizes of atom ; one of the atoms in the majority and generally in a regular arrangement ; [2] (ii) the layers of metal atoms cannot easily slide over each other / owtte ; [1] 8 (a) (i) acceleration = change in speed / time or (–)8 / 40 ; = (–)0.2 (m / s2) ; [2] (b) (calculate the) area under the graph ; further detail such as how to calculate area of rectangle and triangle / add separate areas together ; (8 × 60) + ( 1 2 × 8 × 40) ;; [max 2]

Page 5 Mark Scheme Syllabus Paper Cambridge IGCSE – May/June 2016 0653 33 © Cambridge International Examinations 2016 (c) R and Q ; [1] (d) (i) first reflection at correct angle (by inspection) ; ray passes down fibres and emerges at the other end ; [2] (e) (i) endoscope / key hole surgery ; [1] (ii) surgery not needed or minimal trauma / other correct ; [1] 9 (a) C6H12O6 and 6H2O ; [1] (b) (i) (mucus) traps pathogens / dust / other valid named substance ; (cilia) beat upward to remove mucus from airway ; [2] (ii) cilia become paralysed / move more slowly ; by tar / heat ; so mucus / pathogens / dust not removed from the trachea ; [max 2] (c) collects / picks up oxygen from mother’s blood (in uterus) ; by diffusion ; [2] (d) (i) amniotic (fluid) ; [1] (ii) fetus could be physically damaged / infection / other correct ; [1]