Cambridge IGCSE Sciences - Co-ordinated (Double) 0654 — 2011 Oct/Nov Paper 2 · Variant 1

This document consists of 23 printed pages and 1 blank page. IB11 11_0654_21/4RP © UCLES 2011 [Turn over *0751220488* 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 CO-ORDINATED SCIENCES 0654/21 Paper 2 (Core) October/November 2011 2 hours 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 2011 0654/21/O/N/11 For Examiner's Use 1 (a) Fig. 1.1 shows a section through a human eye. X Y Fig. 1.1 (i) Name parts X and Y. X Y [2] (ii) On Fig. 1.1, draw one ray of light entering the eye and reaching an area where light-sensitive cells are found. [2] (iii) On Fig. 1.1, use a label line and the letter F to label one part of the eye that helps to focus light onto the light-sensitive part of the eye. [1] (iv) Describe how information is sent from the light-sensitive cells to the brain. [2]

3 © UCLES 2011 0654/21/O/N/11 [Turn over For Examiner's Use (b) Almost all cells in the body have a nucleus, which contains chromosomes made of DNA. (i) Name one type of cell in the human body that does not contain a nucleus. [1] (ii) In humans, a sperm cell has 23 chromosomes. Suggest the number of chromosomes that are present in one of the light-sensitive cells in the human eye. [1] (iii) Outline the function of DNA. [2]

4 © UCLES 2011 0654/21/O/N/11 For Examiner's Use 2 Diamonds, sapphires and rubies are found in the Earth’s crust and are valuable as industrial materials and for making jewellery. (a) Table 2.1 shows the numbers of protons, neutrons and electrons in three atoms, X, Y and Z. Table 2.1 atom number of protons number of neutrons number of electrons X 5 6 5 Y 6 7 6 Z 12 12 12 (i) Diamonds are made of the element carbon. Explain which one of the atoms, X, Y or Z, shown in Table 2.1 is a carbon atom. atom explanation [1] (ii) State the nucleon number (mass number) of atom X in Table 2.1. [1] (b) The main compound in sapphires and rubies is aluminium oxide. Aluminium oxide is an ionic compound. (i) Aluminium oxide has the chemical formula, Al2O3. Explain what this formula means. [2]

5 © UCLES 2011 0654/21/O/N/11 [Turn over For Examiner's Use (ii) State one way in which an ion differs from an atom. [1] (c) Fig. 2.1 shows a simplified diagram of a process which is used to obtain metallic aluminium. power supply molten mixture containing aluminium oxide + – Fig. 2.1 (i) Name the process shown in Fig. 2.1, and state the meaning of the word anode. name of process meaning of anode [2] (ii) Explain why the mixture containing aluminium oxide in Fig. 2.1 must be kept molten. [2] (iii) Complete the simple word chemical equation below which describes the main reaction taking place in the process in Fig. 2.1. aluminium oxide + [1]

6 © UCLES 2011 0654/21/O/N/11 For Examiner's Use 3 Fig. 3.1 shows a speed-time graph for the performance of an athlete in a race. A D B C 0 5 10 15 20 25 10 5 0 time / s A D B C speed m / s Fig. 3.1 (a) Use the graph to describe the motion of the athlete between (i) B and C, (ii) C and D. [2] (b) Use the graph to calculate the acceleration of the athlete between A and B. Show your working. m / s2 [2] (c) The athlete runs a distance of 160 m in 25 s. Calculate the average speed of the athlete. State the formula that you use and show your working. formula used working m / s [2]

7 © UCLES 2011 0654/21/O/N/11 [Turn over For Examiner's Use (d) The power output of the athlete is 600 W. Calculate the amount of work done by the athlete over 5 seconds. Show your working. J [2] (e) After the race the athlete is sweating. The sweat evaporates from the surface of the athlete’s skin. Describe the process of evaporation in terms of particles. [2]

8 © UCLES 2011 0654/21/O/N/11 For Examiner's Use 4 (a) Draw lines to link each term to its correct definition. term definition egestion the removal of undigested food through the anus peristalsis breaking large food molecules down to small ones digestion muscular contractions that move food along the alimentary canal absorption the movement of digested food from the alimentary canal into the blood [3] (b) Table 4.1 shows some information about enzymes found in the human alimentary canal. Complete the table. Table 4.1 enzyme substrate product amylase maltose proteins amino acids fatty acids and glycerol [4]

9 © UCLES 2011 0654/21/O/N/11 [Turn over For Examiner's Use (c) Nutrients such as amino acids and glucose are carried from the alimentary canal to the liver. The liver converts any excess amino acids to a nitrogenous waste product. (i) Name this waste product. [1] (ii) Name the organs that excrete this waste product. [1] (iii) The liver converts excess glucose in the blood into glycogen. The glycogen is then stored in cells in the liver. Glycogen is an insoluble substance. Using your knowledge of osmosis, suggest why liver cells might swell and burst if they stored large quantities of a soluble substance such as glucose. [2] (iv) When body cells need glucose, liver cells convert some of their stored glycogen back into glucose. The cells then release the glucose into the blood. Explain why body cells need glucose. [2]

10 © UCLES 2011 0654/21/O/N/11 For Examiner's Use 5 (a) Fig. 5.1 shows a 230 V 60 W light bulb. 230 V 60 W tungsten filament unreactive gas filling bulb glass bulb Fig. 5.1 (i) Explain the meaning of 60 W on the bulb, 230 V on the bulb. [2] (ii) Describe the energy transformations which occur in the light bulb when it has been switched on. [3] (iii) Suggest why the light bulb is filled with an unreactive gas. [1]

11 © UCLES 2011 0654/21/O/N/11 [Turn over For Examiner's Use (b) The graph in Fig. 5.2 shows how the current through a different light bulb changes after it is switched on. 0 20 40 60 80 100 120 140 2.50 2.25 2.00 1.75 1.50 1.25 1.00 0.75 0.50 0.25 0 current / amps time / ms Fig. 5.2 (i) Describe what happens to the current after the bulb is switched on. [2] (ii) Use the graph to find the current through the light bulb 80 ms after it is switched on. A [1]

12 © UCLES 2011 0654/21/O/N/11 For Examiner's Use (c) (i) A lamp with a resistance of 1000 Ω, when lit, is connected in series with another lamp with a resistance of 2000 Ω, when lit. Calculate the combined resistance of these two lamps. State the formula that you use and show your working. formula working Ω [2] (ii) The resistance of a piece of wire depends on a number of variables such as the length of the wire and the material from which it is made. State two other factors which can affect the resistance of a piece of wire. 1 2 [2]

13 © UCLES 2011 0654/21/O/N/11 [Turn over BLANK PAGE Please turn over for Question 6.

14 © UCLES 2011 0654/21/O/N/11 For Examiner's Use 6 (a) Table 6.1 shows some properties of three solid elements A, B and C. Table 6.1 element density electrical conductivity melting point A low high low B low low high C high high high (i) Suggest and explain which element, A, B or C, has properties that are typical of a non-metal. element explanation [1] (ii) Suggest and explain which element, A, B or C, has properties that are typical of a transition metal. element explanation [1]

15 © UCLES 2011 0654/21/O/N/11 [Turn over For Examiner's Use (b) Components in electrical circuits are often joined by soldering them together. Solder is an alloy which has a lower melting point than any of the pure metals it contains. Fig. 6.1 shows part of an electrical circuit into which a resistor has been soldered. plastic circuit board metal connecting strip resistor solder Fig. 6.1 (i) One type of solder is an alloy that contains tin, silver and copper. Describe briefly what must be done to make this solder. [1] (ii) Explain why electrical components are joined by soldering rather than by the use of a non-metallic adhesive (glue). [1] (c) Fig. 6.2 shows part of an electrical cell which a student is making in a school laboratory. volts voltmeter metal electrode e.g. zinc laboratory bench Fig. 6.2 Complete and label the diagram in Fig. 6.2 to show how the cell should appear when the student has finished. [3]

16 © UCLES 2011 0654/21/O/N/11 For Examiner's Use (d) Catalytic converters are used in modern cars to reduce air pollution. Fig. 6.3 shows a simplified diagram of a catalytic converter in a car. catalytic convertor exhaust gases released into the air air and gasoline (hydrocarbon fuel) Fig. 6.3 (i) Name two gaseous compounds that are produced when a hydrocarbon undergoes complete combustion. 1 2 [2] (ii) Suggest one other gas in the exhaust gas mixture whose concentration is reduced by the catalytic converter. [1]

17 © UCLES 2011 0654/21/O/N/11 [Turn over For Examiner's Use 7 (a) Fig. 7.1 shows two children playing in a swimming pool. A B Fig. 7.1 Child A makes some small waves on the surface of the water. (i) In 10 seconds, 5 complete waves pass by child B who is standing in the same pool. Calculate the frequency of the waves. Show your working. Hz [1] (ii) Use suitable words to complete the sentences below to describe what waves do. A wave transfers energy without transferring . The energy is transferred in the direction that the wave . [2] (iii) Water waves are transverse waves. Name one example of a longitudinal wave. [1]

18 © UCLES 2011 0654/21/O/N/11 For Examiner's Use (b) The top of a water slide is 10 m above the water in the pool. This is shown in Fig. 7.2. 10 m Fig. 7.2 A boy has a mass of 50 kg. (i) The gravitational field strength of the Earth is 10 N / kg. State the weight of the boy. N [1] (ii) The boy climbs a vertical distance of 10 m from the pool to the top of the slide. Calculate the work done in gaining this height. State the formula that you use and show your working. formula used working J [2]

19 © UCLES 2011 0654/21/O/N/11 [Turn over For Examiner's Use (iii) The boy slides down to the pool. His speed at the bottom of the slide is 12 m / s. Calculate his kinetic energy at the bottom of the slide. State the formula that you use and show your working. formula used working J [2] (c) The water in the swimming pool is heated by the Sun. State the method of heat transfer by which heat from the Sun reaches the Earth. [1]

20 © UCLES 2011 0654/21/O/N/11 For Examiner's Use 8 The golden lion tamarin, Leontopithecus rosalia, is a monkey that lives in forests in Brazil. Its diet includes fruits and nectar from trees. Its predators include snakes, bamboo rats and owls. (a) (i) State the correct biological term for a two-word Latin name such as Leontopithecus rosalia. [1] (ii) Suggest an advantage of giving each species of organism a Latin name like this. [1] (b) (i) In the space below, use the information provided to construct a food web that includes golden lion tamarins. [3] (ii) On your food web, draw a circle around one producer. [1]

21 © UCLES 2011 0654/21/O/N/11 [Turn over For Examiner's Use (c) Golden lion tamarins are important for the dispersal of seeds from many different species of tree. They eat the fruits and then egest the seeds in their faeces. An investigation was carried out into the distances that golden lion tamarins dispersed seeds from trees. Fig. 8.1 shows the results of a study in which the distances of the tamarins' faeces from one tree were measured. 0 50 100 150 200 250 300 distance from one tree / m 350 400 450 500 550 600 percentage of tamarins’ faeces 40 30 20 10 0 Fig. 8.1 (i) Describe the distribution of golden lion tamarin faeces in relation to this tree. [2] (ii) Suggest two ways in which the dispersal of seeds away from the tree, in golden lion tamarin faeces, could benefit the young plants that grow from the seeds. 1 2 [2]

22 © UCLES 2011 0654/21/O/N/11 For Examiner's Use 9 The manufacture of ammonia is an important industrial process. Fig. 9.1 is a simplified diagram of a reaction vessel which is used to make ammonia. nitrogen (N2) ammonia (NH3) hydrogen (H2) iron catalyst Fig. 9.1 (a) Ammonia is made by combining nitrogen and hydrogen. (i) Explain one difference between an element and a compound. You may use these substances as examples. [2] (ii) Describe a chemical test for ammonia gas. [2]

23 © UCLES 2011 0654/21/O/N/11 For Examiner's Use (b) Ammonia is used to make the compound ammonium nitrate. When it is added to soil, ammonium nitrate is a useful source of nitrogen for plants. Some of the nitrogen taken in by plants is combined with other elements to make amino acids. (i) Explain briefly why nitrogen gas from the air cannot be used directly by most plants. [1] (ii) Suggest a compound that neutralises ammonia to produce ammonium nitrate. [1] (iii) Name the three other elements which are always combined with nitrogen in amino acids. [2] (iv) Describe briefly what happens to amino acid molecules when they form protein molecules. [2] (c) The reaction between nitrogen and hydrogen requires an iron catalyst. (i) State what is meant by the term catalyst. [2] (ii) State one reason why the catalyst in the reaction in Fig. 9.1 could not be made of the alkali metal sodium. [1]

24 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 2011 0654/21/O/N/11 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 October/November 2011 question paper for the guidance of teachers 0654 CO-ORDINATED SCIENCES 0654/21 Paper 2 (Core Theory), maximum raw mark 100 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 October/November 2011 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 – October/November 2011 0654 21 © University of Cambridge International Examinations 2011 1 (a) (i) X retina ; Y optic nerve ; [2] (ii) line drawn starting outside the eye, passing through pupil and lens ; line ends at retina ; [2] (iii) label to either cornea, lens or vitreous humour ; [1] (iv) as impulse / electrical signal / action potentials ; along nerve / along Y ; [2] (b) (i) red blood cell ; [1] (ii) 46 ; [1] (iii) stores information; on making proteins ; ref. to hereditary material ; [max 2] [Total: 11] 2 (a) (i) (Y) (no mark) proton number of 6 ; [1] (ii) 11 ; [1] (b) (i) contains elements aluminium and oxygen ; proportions / number ratio Al : O is 2:3 / owtte ; [2] (ii) ion (electrically) charged / ion protons ≠ electrons ; [1] (c) (i) electrolysis ; positive electrode ; [2] (ii) (contains) ions (which) must be mobile / if solid then ions cannot move ; conduct electrical charge / make an electrolyte; [2] (iii) → aluminium + oxygen ; [1] [Total: 10]

Page 3 Mark Scheme: Teachers’ version Syllabus Paper IGCSE – October/November 2011 0654 21 © University of Cambridge International Examinations 2011 3 (a) (i) constant speed ; [1] (ii) deceleration / slowing down ; [1] (b) 8 / 5 ; = 1.6 (m / s2) ; [2] (c) speed =) distance / time ; = 160 / 25 = 6.4 (m / s) ; [2] (d) (energy =) power × time ; = 600 × 5 = 3000 (J) ; [2] (e) heat transferred to (water) particles (from surroundings) ; (water) changes from liquid to gas ; ref. to attraction between particles in the liquid ; fastest moving particles escape ; (escape) at surface / ref. to process happening at temperature below boiling point ; average energy of the rest of the particles reduced / heat removed from liquid ; [max 2] [Total: 10] 4 (a) term definition egestion the removal of undigested food through the anus peristalsis breaking large food molecules down to small ones digestion muscular contractions that move food along the alimentary canal absorption the movement of digested food from the alimentary canal into the blood all correct for 3 marks, 2 or 3 correct for 2 marks, 1 correct for 1 mark ;;; [3]

Page 4 Mark Scheme: Teachers’ version Syllabus Paper IGCSE – October/November 2011 0654 21 © University of Cambridge International Examinations 2011 (b) enzyme substrate product amylase starch ; maltose protease ; proteins amino acids lipase ; fats / lipids ; fatty acids and glycerol [4] (c) (i) urea ; [1] (ii) kidneys ; [1] (iii) cells might take up water ; because concentration inside cells is greater than outside ; [2] (iv) for energy ; respiration ; glucose oxidised / glucose combined with oxygen ; for movement / other named use of energy ; [max 2] [Total: 13] 5 (a) (i) the power rating of bulb / how much energy is transferred per second ; the voltage / potential difference that the bulb operates at ; [2] (ii) electrical ; into light ; into heat ; [3] (iii) gas will not react with hot filament / reduces oxidation ; [1] (b) (i) decreases ; to constant (minimum) value ; [2] (ii) 0.20 (A) ; [1] (c) (i) RT = R1 + R2 ; (= 1000 + 2000) R = 3000 (Ω) ; [2] (ii) cross sectional area / thickness ; temperature of wire ; [2] [Total: 13]

Page 5 Mark Scheme: Teachers’ version Syllabus Paper IGCSE – October/November 2011 0654 21 © University of Cambridge International Examinations 2011 6 (a) (i) (B) low electrical conductivity ; [1] (ii) (C) high density and (high) electrical conductivity ; [1] (b) (i) all three metals must be melted together ; [1] (ii) solder maintains the electrical connection / owtte ; [1] (c) second electrode ; container plus liquid ; suitable named electrolyte (into which electrodes are placed) ; indication that second electrode is a different metal ; indication that pd is produced e.g. value on voltmeter ; [max 3] (d) (i) carbon dioxide ; water (vapour) ; [2] (ii) carbon monoxide / NOx or specific example / hydrocarbons ; [1] [Total: 10] 7 (a) (i) (frequency =) 0.5 (Hz) ; [1] (ii) matter / mass ; travels / moves / goes ; [2] (iii) sound / ultra sound / infrasound ; [1] (b) (i) 500 (N) ; [1] (ii) (work done =) force × distance ; = 500 × 10 = 5000 (J) ; [2] (iii) (kinetic energy =) ½ mv2 ; = ½ × 50 × 12 × 12 = 3600 (J) ; [2] (c) radiation ; [1] [Total: 10]

Page 6 Mark Scheme: Teachers’ version Syllabus Paper IGCSE – October/November 2011 0654 21 © University of Cambridge International Examinations 2011 8 (a) (i) binomial ; [1] (ii) idea that it is the same all over the world / in every language ; [1] (b) (i) trees / nectar / fruit (allow if in separate boxes) golden lion tamarins bamboo rats snakes owls plants and tamarins connection correct ; all three predators connection correct ; all arrows in right direction ; [3] (ii) circle round tree, nectar or fruit ; [1] (c) (i) fewer faeces further from tree ; furthest distance from tree is 400 m ; figures quoted, e.g. 31% of faeces deposited within 50 m of tree ; [max 2] (ii) faeces provide nutrients for, young plants / seedlings (not seeds) ; less competition (for seedlings) away from parent tree ; factor competed for – water / light ; help to colonise new areas ; [max 2] [Total: 10]

Page 7 Mark Scheme: Teachers’ version Syllabus Paper IGCSE – October/November 2011 0654 21 © University of Cambridge International Examinations 2011 9 (a) (i) element made of one type of atom / found in Periodic Table ; compound made of two or more different elements ; [2] (ii) (damp red) litmus paper / (red) litmus solution / full range / Universal Indicator ; turns blue ; [2] (b) (i) nitrogen inert / difficult to break N2 molecule ; [1] (ii) nitric acid ; [1] (iii) carbon, hydrogen, oxygen ;; [2] (all three – 2 marks, only two correct – 1 mark) (iv) join / link / react together ; to form a (long) chain ; [2] (c) (i) increases rate of reaction ; not consumed / used up / can be regenerated ; [2] (ii) it would react / corrode / sodium does not have catalytic properties / sodium not a transition metal ; [1] [Total: 13]