CIE Nov 2017 v4 Paper 3 Q2

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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 reagents are selected for use in a test, the name or correct formula of the element or compound must be given. Where gases are released they should be identified by a test, described in the appropriate place in your observations. You should indicate clearly at what stage in a test a change occurs. 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. (a) FB 3, FB 4, FB 5 and FB 6 are aqueous solutions each containing one cation and one anion. (i) Carry out the following tests by adding, to a 1 cm depth of each solution in a test-tube, a 1 cm depth of the other solution. Record your observations in the table. FB 4 observations FB 5 FB 6 test FB 3 FB 4 FB 5UCLES 2017 9701/34/O/N/17 [Turn over<br /> PMT (ii) FB 3 and FB 4 both contain the same anion. Use your observations from (i) to suggest the identity of this anion. anion:(iii) Suggest and carry out a test to confirm the identity of the anion you identified in (ii). You should include the test and your result. testresult(iv) FB 5 contains one cation from those listed in the Qualitative Analysis Notes. Use your observations in (i) to suggest two cations that could be present in FB 5. cations presentor(v) Suggest and carry out a test to identify which of the cations you suggested in (iv) is present in FB 5. testresultcation present in FB 5[9]UCLES 2017 9701/34/O/N/17<br /> (b) FB 7, FB 8 and FB 9 are aqueous solutions. (i) Carry out the following tests and record your observations. PMT FB 7 observations FB 8 FB 9 test To a 1 cm depth of solution in a test-tube add a 1 cm depth of aqueous potassium iodide, then add aqueous starch. To a 1 cm depth of solution in a test-tube add a 1 cm depth of aqueous iodine. To a 1 cm depth of solution in a test-tube add a few drops of aqueous barium nitrate or aqueous barium chloride. (ii) From your observations in (i) suggest two anions from those listed in the Qualitative Analysis Notes that could be present in FB 9. anions presentor(iii) Suggest and carry out a test to identify which of the anions you suggested in (ii) is present in FB 9. testresultanion present in FB 9[6] [Total: 15]UCLES 2017 9701/34/O/N/17 [Turn over<br />

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