CIE Nov 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) You are provided with two solids in boiling tubes labelled FB 5 and FB 6. Each solid contains one cation and one anion from those listed on pages 10 and 11. (i) Add dilute nitric acid slowly to each boiling tube until the tube is approximately one third full. Record your observations in the space below. Keep these solutions for use in (a)(ii).UCLES 2013 9701/34/O/N/13 [Turn over<br /> Examiners For Use (ii) Use the solutions from (i) in the following tests. observations solution from FB 5 solution from FB 6 test To a 1 cm depth of solution in a test-tube add aqueous sodium hydroxide, then add excess aqueous sodium hydroxide. To a 1 cm depth of solution in a test-tube add aqueous ammonia, then add excess aqueous ammonia. To a 1 cm depth of solution in a test-tube, add aqueous potassium iodide. (iii) From your observations, identify the cations present. FB 5 containsFB 6 contains(iv) From your observations, what conclusions can be made about the anions present in FB 5 and FB 6? Explain your reasoning.[9]UCLES 2013 9701/34/O/N/13<br /> Examiners For Use (b) (i) Dissolve half of the solid FB 7 provided in a 4 cm depth of water in a boiling tube. Carry out the following tests and complete the table. test observations deductions about FB 7 To a 2 cm depth of the solution of FB 7 in a test-tube, add a 2 cm length of magnesium ribbon. To a 2 cm depth of the solution of FB 7 in a boiling tube, add a 1 cm depth of dilute sulfuric acid. Warm the solution and addve drops of aqueous potassium manganate(VII). (ii) Tip the remaining solid FB 7 into a hard-glass test-tube. Heat the solid strongly and observe any changes. Do not test any gases given off. Record your observations in the space below. (iii) Suggest a further deduction you can make about FB 7 from your observations in (ii).[6] [Total: 15]UCLES 2013 9701/34/O/N/13 [Turn over<br />

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