CIE Nov 2017 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 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.UCLES 2017 9701/35/O/N/17 [Turn over<br /> PMT FA 6, FA 7 and FA 8 are solutions of salts. Information about FA 6, FA 7 and FA 8Each salt contains one cation and one anion. One of the ions is sodium; the other five ions are listed in the Qualitative Analysis Notes. Each salt contains a different nitrogen-containing ion. FA 7 or FA 8 contains a halide ion. (a) You will identify the cations present in FA 6, FA 7 and FA 8. To do this you will carry out six separate tests. You will use dilute sulfuric acid and aqueous sodium hydroxide separately with FA 6, FA 7 and FA 8. Use a 1 cm depth of each salt solution in a suitable tube for each test you carry out. Record all of your observations in a table in the space below.UCLES 2017 9701/35/O/N/17 [4]<br /> PMT (b) Name the reagents you would use to identify the halide ion present in either FA 7 or FA 8. Test FA 7 and FA 8 with these reagents and record your observations. reagents usedunknown observations halide ion present /FA 7 FA 8 (c) (i) Name the reagents you would use to confirm the presence of the nitrogen-containing anions in the two solutions that do not contain a halide ion. Test both solutions with these reagents and record your observations. reagents used[2] observations unknown FAFA(ii) Name the reagent you would use to positively identify one of the nitrogen-containing anions in the two solutions tested in (i). Test both solutions with this reagent. Record all your observations. reagent usedobservations unknown FAFA(d) Use the information given in (a) and your observations in all tests to deduce the chemical formulae of the three salts. FA 6 isFA 7 isFA 8 is[2] [4]UCLES 2017 9701/35/O/N/17 [Total: 12] [Turn over<br />

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