CIE Jun 2016 v3 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 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. 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) FA 5, FA 6, FA 7 and FA 8 are aqueous solutions of organic compounds. All of FA 5, FA 6, FA 7 and FA 8 contain carbon, hydrogen and oxygen only. Half fill the 250 cm3 beaker with water and heat it to about 80 C. Turn off the Bunsen burner. This will be used as a water bath. To a 2 cm depth of aqueous silver nitrate in a boiling tube add 2 drops of aqueous sodium hydroxide and then add ammonia dropwise until the brown solid just disappears. This solution is Tollens reagent and is needed in a test in (i).UCLES 2016 9701/33/M/J/16 [Turn over<br /> (i) Carry out the following tests on FA 5, FA 6, FA 7 and FA 8 and record your observations in the table. PMT FA 5 FA 6 FA 7 FA 8 observations test To a 1 cm depth in a test-tube, add a small spatula measure of sodium carbonate. To a few drops in a test-tube, add a 1 cm depth of Tollens reagent. Place the tube in the water bath and leave to stand. When you have completed this test rinse all tubes used. To a 1 cm depth in a test-tube, add a few drops of acidified potassium manganate(VII). Place the tube in the water bath and leave to stand. (ii) Using your observations from the table, what functional group is present in both FA 5 and FA 6?(iii) Using your observations from the table, what functional group is present in both FA 5 and FA 8?(iv) What type of reaction is occurring in the potassium manganate(VII) test?(v) Using your observations from the table, what functional group is present in FA 7?UCLES 2016 9701/33/M/J/16<br /> PMT (vi) Suggest a test that would confirm the presence of the functional group in a pure sample of FA 7. Include the result you would expect the test to give. Do not carry out this test.[9] (b) FA 9 and FA 10 are solids that each contain one anion from those listed in the Qualitative Analysis Notes on page 11. (i) Carry out the following tests on FA 9 and FA 10 and record your observations in the table. observations FA 9 FA 10 test To a spatula measure of solid in a boiling tube, add a 1 cm depth of aqueous sodium hydroxide. Warm, then, add a small piece of aluminium foil. Place a spatula measure of solid in a hard-glass test-tube. Heat gently at first and then more strongly. (ii) Using your observations from the table, which two anions could be present in FA 9 and FA 10? anionor(iii) Suggest a test that would allow you to decide which of the anions is present. State what observations you would expect.(iv) Carry out this test on FA 9 and FA 10 to decide which anion is present in each. observation for FA 9anion in FA 9 isobservation for FA 10anion in FA 10 is[7]UCLES 2016 9701/33/M/J/16 [Total: 16] [Turn over<br />

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