CIE Jun 2014 v5 Paper 3 Q3

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PMT 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.UCLES 2014 9701/35/M/J/14<br /> (a) You are provided with a different sample of zinc carbonate ore, labelled FA 5. This sample contains zinc carbonate, ZnCO3, and one other salt. This additional salt contains a single cation and a single anion from those listed on pages 11 and 12. By carrying out the following tests you will be able to suggest the identities of the ions in the additional salt. test observations PMT (i) Transfer the solid FA 5 into a boiling tube and add a 3 cm depth of dilute nitric acid to make solution FA 6. Use this solution in tests (ii) to (v). (ii) To a 1 cm depth of FA 6 in a test-tube, add aqueous sodium hydroxide. (iii) To a 1 cm depth of FA 6 in a test-tube, add aqueous ammonia. (iv) To a 1 cm depth of FA 6 in a test-tube, add a 1 cm depth of aqueous silver nitrate. (v) To a 1 cm depth of FA 6 in a test-tube, add a 1 cm depth of aqueous barium chloride or barium nitrate. (vi) Suggest the identity of the cation and anion (apart from Zn2+ and CO3 Explain your choice. 2) present in FA 5. cationreasonanionreason[7] II III IV VI VIIUCLES 2014 9701/35/M/J/14 [Turn over<br /> PMT (b) You are provided with solid FA 7, which is a mixture of two salts. Use separate portions of FA 7 to perform the experiments below. 10 test observations (i) Heat a spatula measure of FA 7 in a hard-glass test-tube gently atrst, then heat more strongly and test the gas evolved with litmus paper. Dissolve a spatula measure of FA 7 in a test-tube with a 5 cm depth of distilled water for use in tests (ii) and (iii). (ii) To a 1 cm depth of FA 7(aq) in a test-tube, add aqueous silver nitrate, followed by aqueous ammonia. (iii) To a 1 cm depth of FA 7(aq) add barium chloride or barium nitrate, followed by dilute nitric acid. (iv) Use your observations and the Qualitative Analysis Notes from pages 11 and 12 to identify three of the ions present. Give evidence for your choice of ions. ionevidenceionevidenceionevidence[6] [Total: 13] II III IV VIUCLES 2014 9701/35/M/J/14<br />

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