GCSE Additional Science May 2008 Ideas in Context Paper B

This document consists of 11 printed pages, 1 blank page and an insert. SPA (SHW 00054 5/07) T48676/5 © OCR 2008 [K/103/3777] OCR is an exempt Charity [Turn over INSTRUCTIONS TO CANDIDATES • Write your name in capital letters, your Centre Number and Candidate Number in the boxes above. • Use blue or black ink. Pencil may be used for graphs and diagrams only. • Read each question carefully and make sure that you know what you have to do before starting your answer. • Answer all the questions. • Do not write in the bar codes. • Write your answer to each question in the space provided. INFORMATION FOR CANDIDATES • The number of marks for each question is given in brackets [ ] at the end of each question or part question. • The total number of marks for this paper is 40. • A list of physics equations is printed on page two. • The Periodic Table is printed on the back page. • Where you see this icon you will be awarded a mark for the quality of written communication in your answer. * C U P /T 4 8 6 7 6 * FOR EXAMINER’S USE Qu. Max. Mark 1 12 2 14 3 14 TOTAL 40 GENERAL CERTIFICATE OF SECONDARY EDUCATION A218/02 TWENTY FIRST CENTURY SCIENCE ADDITIONAL SCIENCE A Unit 4: Ideas in Context (Higher Tier) FRIDAY 23 MAY 2008 Afternoon Time: 45 minutes Candidates answer on the question paper. Additional materials (enclosed): Insert Calculators may be used. Additional materials: Pencil Ruler (cm/mm) H2 © OCR 2008 EQUATIONS Useful Relationships Explaining Motion speed = distance travelled time taken momentum = mass × velocity change of momentum = resultant force × time for which it acts work done by a force = force × distance moved by the force change in energy = work done change in GPE = weight × vertical height difference kinetic energy = 12 × mass × [velocity]2 Electric Circuits resistance = voltage current Vp Vs = Np Ns energy transferred = power × time power = potential difference × current efficiency = energy usefully transferred total energy supplied × 100% The Wave Model of Radiation wave speed = frequency × wavelength3 [Turn over © OCR 2008 BLANK PAGE PLEASE DO NOT WRITE ON THIS PAGE Question 1 starts on page 44 © OCR 2008 Answer all the questions. This question is based on the article ‘Tufa towers at Mono Lake, California’. 1 (a) The tufa rock is made from calcium carbonate. The calcium carbonate forms when calcium ions in the hot springs react with carbonate ions in the lake water. (i) Complete the equation for the reaction by filling in the missing formula and state symbols. Ca2+(……) + CO32– (……) …………… (……) [2] (ii) Tufa towers only form around the hot springs. They do not form at other places in the lake. Explain why. .......................................................................................................................................... .................................................................................................................................... [2] (b) Calcium carbonate is an ionic solid. The table shows some information about ions dissolved in lake water and ions in solid calcium carbonate. Complete the table. ions dissolved in the lake water ions in solid calcium carbonate movement of ions move freely around other ions and water molecules arrangement of ions random arrangement [2] (c) Joe visits the lake and carries out some experiments. He finds that the water is a good electrical conductor. Explain how water that contains dissolved ionic compounds conducts electricity. .................................................................................................................................................. ............................................................................................................................................ [2]5 [Turn over © OCR 2008 (d) The salt crystals at the edge of the lake contain sodium chloride and magnesium chloride. name formula sodium chloride NaCl magnesium chloride MgCl 2 Chloride ions have a charge of –1. Explain why the formulae of these two salts contain different numbers of chloride ions. .................................................................................................................................................. ............................................................................................................................................ [1] (e) The article gives a recipe for making fake lake water. (i) Give one way the fake lake water is similar to the real thing. .................................................................................................................................... [1] (ii) Suggest two ways that the fake lake water is different from the real thing. .......................................................................................................................................... .................................................................................................................................... [2] [Total: 12]6 © OCR 2008 This question is based on the article ‘Bendy lampposts save lives’. 2 (a) The article says that the momentum of the car can be reduced by about 30%. (i) What two measurements do scientists need to make to calculate momentum? How do you use the measurements to calculate momentum? One mark is for a clear, ordered answer. .......................................................................................................................................... .......................................................................................................................................... .......................................................................................................................................... ................................................................................................................................ [3+1] (ii) Any collision involves two forces. One force changes the momentum of the car. What does the other force do? .......................................................................................................................................... .................................................................................................................................... [1]7 [Turn over © OCR 2008 (b) The graph shows how the force on the car changes with how long the collision lasts. force on car how long the collision lasts Explain how a bendy lamppost reduces injuries in a collision. Use the graph to help you. .................................................................................................................................................. .................................................................................................................................................. .................................................................................................................................................. ............................................................................................................................................ [2]8 © OCR 2008 (c) The speed of the car changes during and after a collision with a lamppost which breaks during the collision. The car travels at 30 mph. It then hits the lamppost. The lamppost reduces the momentum of the car by one third. After hitting the lamppost, the driver stops the car. Draw a line on the graph to show how the car’s speed changes with time. 100 20 30 collision car stops time speed in mph [3]9 [Turn over © OCR 2008 (d) If the car hits the newest type of lamppost, it can slide up the lamppost during the crash. (i) When the car has slid up the lamppost, the gain in gravitational potential energy is 22 500 Joules. Calculate what the speed of the car had been if all its kinetic energy was transferred to gravitational potential energy. Mass of car = 1500 kg You must show your working. speed = ................................................. m /s [3] (ii) The speed you calculated is less than the actual speed. Explain why. .......................................................................................................................................... .................................................................................................................................... [1] [Total: 14]10 © OCR 2008 This question is based on the article ‘Cot deaths linked to brain abnormality’. 3 (a) The pictures show scans through part of the brain called the cerebral cortex. Describe two functions of the cerebral cortex. .................................................................................................................................................. .................................................................................................................................................. ............................................................................................................................................ [2] (b) Kinney and Paterson thought that a lack of receptors for serotonin was responsible for SIDS. Look at the article about cot deaths and suggest two reasons why the evidence is not conclusive. .................................................................................................................................................. .................................................................................................................................................. ............................................................................................................................................ [2] (c) The diagram shows how serotonin is produced by neurons in the cerebral cortex of a normal baby’s brain. synaptic vesicle synapse serotonin (neurotransmitter) sensory neuron receptor (i) Describe how the diagram might be different for a baby who later died of SIDS. .......................................................................................................................................... .................................................................................................................................... [1]11 © OCR 2008 (ii) Use the diagram to explain how chemicals carry the impulse across the synapse. .......................................................................................................................................... .......................................................................................................................................... .......................................................................................................................................... .................................................................................................................................... [3] (d) Babies who died from SIDS had greater numbers of neurons which produce serotonin. Explain why the high levels of serotonin in the cerebral cortex did not stop the babies dying from SIDS. .................................................................................................................................................. .................................................................................................................................................. ............................................................................................................................................ [2] (e) The drug ecstasy blocks the removal of serotonin. (i) Suggest the effect of ecstasy on the gasping reflex in newborn babies. Explain your answer. .......................................................................................................................................... .......................................................................................................................................... .......................................................................................................................................... .......................................................................................................................................... .................................................................................................................................... [3] (ii) Describe one other effect that ecstasy has on the brain. .......................................................................................................................................... .................................................................................................................................... [1] [Total: 14] END OF QUESTION PAPER 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 (OCR) 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. OCR 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.12 © OCR 2008 The Periodic Table of the Elements * The lanthanoids (atomic numbers 58-71) and the actinoids (atomic numbers 90-103) have been omitted. The relative atomic masses of copper and chlorine have not been rounded to the nearest whole number. 1 2 3 4 5 6 7 0 Key 1Hhydrogen 1 4 He helium 2 7 Li lithium 3 9 Be beryllium 4 relative atomic mass atomic symbol name atomic (proton) number 11 B boron 5 12 C carbon 6 14 N nitrogen 7 16 O oxygen 8 19 F fluorine 9 20 Ne neon 10 23 Na sodium 11 24 Mg magnesium 12 27 Al aluminium 13 28 Si silicon 14 31 P phosphorus 15 32 S sulfur 16 35.5 Cl chlorine 17 40 Ar argon 18 39 K potassium 19 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 63.5 Cu copper 29 65 Zn zinc 30 70 Ga gallium 31 73 Ge germanium 32 75 As arsenic 33 79 Se selenium 34 80 Br bromine 35 84 Kr krypton 36 85 Rb rubidium 37 88 Sr strontium 38 89 Y yttrium 39 91 Zr zirconium 40 93 Nb niobium 41 96 Mo molybdenum 42 [98] 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 54 133 Cs caesium 55 137 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 [209] Po polonium 84 [210] At astatine 85 [222] Rn radon 86 [223] Fr francium 87 [226] Ra radium 88 [227] Ac* actinium 89 [261] Rf rutherfordium 104 [262] Db dubnium 105 [266] Sg seaborgium 106 [264] Bh bohrium 107 [277] Hs hassium 108 [268] Mt meitnerium 109 [271] Ds darmstadtium 110 [272] Rg roentgenium 111 Elements with atomic numbers 112-116 have been reported but not fully authenticated