Cambridge IGCSE Sciences - Co-ordinated (Double) 0654 — 2008 Oct/Nov Paper 5 · Variant 1

This document consists of 10 printed pages and 2 blank pages. IB08 11_0654_05/7RP © UCLES 2008 [Turn over *0370929476* For Examiner's Use 1 2 3 Total UNIVERSITY OF CAMBRIDGE INTERNATIONAL EXAMINATIONS International General Certificate of Secondary Education CO-ORDINATED SCIENCES 0654/05 Paper 5 Practical Test October/November 2008 2 hours Candidates answer on the Question Paper. Additional Materials: As listed in Instructions to Supervisors 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 pencil for any diagrams, graphs or rough working. Do not use staples, paper clips, highlighters, glue or correction fluid. DO NOT WRITE IN ANY BARCODES. Answer all questions. Chemistry practical notes for this paper are printed on page 12. 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 2008 0654/05/O/N/08 For Examiner's Use 1 The experiment has been set up to investigate the effect of light on the growth of seedlings. The seeds were set up for germination in boxes A, B and C as shown in Fig. 1.1 and left for a few days. box A completely closed box B open at the top box C open at one side seed cotton wool dish water light light Fig. 1.1 (a) (i) Name one condition that was kept the same to make the test fair. [1] The labelled specimens A, B and C are groups of seedlings from each box. (ii) Without removing the seedlings from the cotton wool, draw in Fig. 1.2 one seedling from each dish. [3] observation A B C drawing of seedling from dish colour of leaves vertical height of seedling / mm Fig. 1.2 (iii) Write the colour of the leaves of each batch of seedlings, A, B and C in Fig. 1.2. [1]

3 © UCLES 2008 0654/05/O/N/08 [Turn over For Examiner's Use (iv) Measure the vertical height in millimetres of the tallest seedling in each group as shown in Fig. 1.3. Enter the measurements in Fig. 1.2. [3] vertical height Fig. 1.3 (v) For seedling B only, measure the height of the drawing and use the vertical height measurement from Fig. 1.2 to calculate the magnification of your drawing. height of drawing = mm magnification = mm [3] (b) The growth of seedlings is different in all three boxes. Explain why the seedlings in boxes A and C grew differently from the seedlings in box B. box A box C [2] (c) Suggest a modification of the apparatus to compare the growth of seedlings in red and green light. [2]

4 © UCLES 2008 0654/05/O/N/08 For Examiner's Use 2 You are going to make various measurements with a spring that will enable you to determine a value for the acceleration of free fall, g. Set up the apparatus as shown in Fig. 2.1. Make sure that there is sufficient room below the spring to allow for stretching and that the rule is clamped with the zero at the bottom. 0 metre rule spring hanger Fig. 2.1 (a) Read and record the position of the bottom of the hanger. • Add a 200 g mass to the hanger. • Using the metre rule read, and record the new position of the bottom of the hanger. • Calculate the extension, E, which is the difference between the two values. position of hanger with no mass added = mm position of hanger with 200 g mass = mm extension, E = mm [1]

5 0654/05/O/N/08 [Turn over For Examiner's Use BLANK PAGE Question 2 continues on Page 6.

6 © UCLES 2008 0654/05/O/N/08 For Examiner's Use (b) Replace the 200 g mass with 150 g. • Remove the metre rule • Pull down the hanger about 20 mm and release it to allow the spring to gently oscillate in a vertical direction. • Time 20 oscillations and record this time in Fig. 2.3. Fig. 2.2 may help you to understand what is meant by one complete oscillation. release rest position start time end time Fig. 2.2 (c) You are now going to repeat the timing of 20 oscillations three more times using different masses. Choose a range of masses in the region 150 g to 300 g. Record the times in Fig. 2.3. mass / g time for 20 oscillations / s T / s time for 1 oscillation T2 / s2 150 Fig. 2.3 [4] (d) Complete Fig. 2.3 by calculating the time, T, for 1 oscillation. This is done by dividing the time for 20 oscillations by 20. Then square each value to calculate T2 to two decimal places.

7 © UCLES 2008 0654/05/O/N/08 [Turn over For Examiner's Use (e) Plot a graph of T2 (vertical axis) against the mass. Draw the best straight line through your points. [4] (f) Use the graph to measure the gradient of the line. Show clearly on your graph how you did this. [2] (g) Use the gradient from (f) and the extension, E, from (a) to find the value of g, using the formula, g = E x 0.0002 gradient [2]

8 © UCLES 2008 0654/05/O/N/08 For Examiner's Use (h) How could you improve the accuracy of this experiment? Suggest at least two ways by which this could be achieved. [2]

9 © UCLES 2008 0654/05/O/N/08 [Turn over For Examiner's Use 3 You are provided with two solids, A and C, and a solution of an iron salt labelled B. Carry out the following tests, recording all your observations in the appropriate spaces. (a) Dissolve about three quarters of solid A in 20 cm3 of water. Use about 2 cm3 portions for each of the following tests. (i) To about 2 cm3 of the solution of A, add aqueous barium chloride followed by dilute hydrochloric acid. observation [1] (ii) To about 2 cm3 of the solution of A, add the piece of magnesium ribbon and test any gas with a lighted spill. observation result of test with lighted spill name of gas [3] (iii) To about 2 cm3 of the solution of A add solid sodium carbonate. observation [1] (iv) What two facts can you deduce about solid A? [2] (b) Solution B is iron chloride. You are required to carry out an experiment of your own to decide whether it is iron(II) or iron(III) chloride. Describe your test and observations, clearly stating which compound of iron is present. Keep a 1 cm3 portion of solution B for use in (c)(iii). test observation result [3]

10 © UCLES 2008 0654/05/O/N/08 For Examiner's Use (c) Dissolve solid C in about 10 cm3 of warm water. Use about 2 cm3 portions of this solution for each of the following tests. (i) Dip a piece of filter paper into solution X and then into a 2 cm3 portion of solution C. observation [1] (ii) To about 2 cm3 of the solution of C, add aqueous barium chloride, followed by dilute hydrochloric acid observation [2] (iii) Place about 1 cm3 of solution B in a large test-tube. Add a 2 cm3 portion of solution C and about 3 cm3 dilute hydrochloric acid and bring to the boil. After cooling, add aqueous sodium hydroxide until no further change is seen. observation [1] (d) What chemical change has taken place in solution B? [1]

12 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 2008 0654/05/O/N/08 CHEMISTRY PRACTICAL NOTES Test for anions anion test test result carbonate (CO3 2–) add dilute acid effervescence, carbon dioxide produced chloride (Cl–) [in solution] acidify with dilute nitric acid, then add aqueous silver nitrate white ppt. nitrate (NO3 –) [in solution] add aqueous sodium hydroxide then aluminium foil; warm carefully ammonia produced sulphate (SO4 2–) [in solution] acidify then add aqueous barium chloride or aqueous barium nitrate white ppt. Test for aqueous cations cation effect of aqueous sodium hydroxide effect of aqueous ammonia ammonium (NH4 +) ammonia produced on warming - copper(II) (Cu2+) light blue ppt., insoluble in excess light blue ppt., soluble in excess giving a dark blue solution iron(II) (Fe2+) green ppt., insoluble in excess green ppt., insoluble in excess iron(III) (Fe3+) red-brown ppt., insoluble in excess red-brown ppt., insoluble in excess zinc (Zn2+) white ppt., soluble in excess giving a colourless solution white ppt., soluble in excess, giving a colourless solution Test for gases gas test and test results ammonia (NH3) turns damp litmus paper blue carbon dioxide (CO2) turns limewater milky chlorine (Cl2) bleaches damp litmus paper hydrogen (H2) “pops” with a lighted splint oxygen (O2) relights a glowing splint

UNIVERSITY OF CAMBRIDGE INTERNATIONAL EXAMINATIONS International General Certificate of Secondary Education MARK SCHEME for the October/November 2008 question paper 0654 CO-ORDINATED SCIENCES 0654/05 Paper 5 (Practical), maximum raw mark 45 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. All Examiners are instructed that alternative correct answers and unexpected approaches in candidates’ scripts must be given marks that fairly reflect the relevant knowledge and skills demonstrated. Mark schemes must be read in conjunction with the question papers and the report on the examination. • CIE will not enter into discussions or correspondence in connection with these mark schemes. CIE is publishing the mark schemes for the October/November 2008 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 Syllabus Paper IGCSE – October/November 2008 0654 05 © UCLES 2008 1 (a) (i) temperature/amount of water; [1] (ii) A should be tallest and straight; B should be shorter and straight; C should be curved; (subtract 1 mark for drawings of poor quality) [3] (iii) line of table should be filled in yellow, green, green; [1] (iv) values should be as follows: A should be largest number; B should be second; C should be third; [3] (v) magnification = size of image; size of object substitution of candidates values; answer; [3] (b) box A, plant grows upwards more quickly/etiolation to reach light (for photosynthesis); box C, plant bends towards the light/phototropism, to improve light capture (for photosynthesis); [2] (c) set up two boxes as in box B; put a red filter across top of one and a green filter across the other; compare growth after a few days; all other conditions identical/one controlled condition named; [2 max] [Total: 15] 2 (a) value of E correct. Do not allow if clearly not mm allow if values are reversed [1] (c) FOUR complete sets of readings i.e. for 20 oscillations suitable range of masses T correct must have at least 3 readings of 20 osc T2 correct to 2 dp [4] (e) axes correct and labelled with units no marks for graph if wrong things plotted scale is sensible plotting correct best straight line for their points and is reasonable st. line [4] (f) gradient is shown on graph for any reasonable st.line correctly calculated if line is made up of parts, NO marks for (f) allow if area involving the plots is used [2]

Page 3 Mark Scheme Syllabus Paper IGCSE – October/November 2008 0654 05 © UCLES 2008 (g) correctly calculated for candidate’s figures accuracy – between 8 and 10 do not allow this mark if st.line mark not given [2] (h) any reasonable answer – one mark for each allow ‘repeating more times’ [2] [Total: 15] 3 (a) (i) white ppt Do not allow ‘milky’ [1] (ii) fizzes pops hydrogen only if ‘pops’ is given [3] (iii) effervescence/bubbles OR Mg disappears [1] it is an acid contains sulfate allow one if sulfuric acid [2] (b) addition of sodium hydroxide allow Na2CO3 or aq NH3 red brown ppt iron(III) [3] (c) (i) decolourised/loses its colour/goes white [1] (ii) white ppt dissolves in the acid [2] (iii) dirty green ppt [1] (d) the iron(III) has been changed to iron(II) OR the iron has been reduced OR WTTE [1] [Total: 15]