CIE Jun 2013 v4 Paper 3 Q3

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Examiners For Use Qualitative Analysis At each stage of any test you are to record details of the following.colour changes seen the formation of any precipitate the solubility of such precipitates in an excess of the reagent added Where gases are released they should be identi ed by a test, described in the appropriate place in your observations. You should indicate clearly at what stage in a test a change occurs. Marks are not given for chemical equations. No additional tests for ions present should be attempted. If any solution is warmed, a boiling tube MUST be used. Rinse and reuse test-tubes and boiling tubes where possible. Where reagents are selected for use in a test, the name or correct formula of the element or compound must be given. (a) FB 5, FB 6, FB 7 and FB 8 are aqueous solutions each of which contains a single cation and a single anion. Some of the ions present are listed below. Fe2+ Pb2+ Zn2+ I OH SO4 2 By observing the reactions that occur when pairs of the solutions are mixed together, you will be able to identify which solution contains which of these ions.UCLES 2013 9701/34/M/J/13 [Turn over<br /> 10To a 1 cm depth of FB 6, FB 7 and FB 8 in separate test-tubes add FB 5 dropwise until in excess. Leave each test-tube to stand for a few minutes and note any changes. Use a 1 cm depth of each solution for the remaining tests. Record your observations in the following table. FB 6 FB 7 FB 8 Examiners For Use FB 5 FB 6 FB 7 (b) From your observations deduce which solution contains each of the following ions. Fe2+ Pb2+ Zn2+ I OH SO4 2 ion solutionUCLES 2013 9701/34/M/J/13 II III IV VI II III [6] [3]<br /> 11 (c) FB 9 is an aqueous solution containing either sulfate, SO4 Describe how you would determine which ion is present. 2, or sul te, SO3 2, ions.Carry out this test and record your observations and conclusion. observationsThe anion in FB 9 is. [2] (d) A student is given two different samples and told that each contains one of the following organic compounds. ethanol ethanal ethanoic acid Describe two chemical tests that the student could carry out on each sample to determine which organic compound is present in each sample. For each test, give the reagent(s) to be used and explain how the different observations would allow the identity of the sample to be determined.rst reagentobservationsexplanationsecond reagentobservationsexplanation[4] [Total: 15] Examiners For Use II III IVUCLES 2013 9701/34/M/J/13 [Turn over<br />

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