CIE Jun 2014 v1 Paper 3 Q3

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Qualitative Analysis PMT 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) FA 6 is a solution of two different salts. It contains two different cations, one of which is listed in the Qualitative Analysis Notes on page 10. It contains two anions, both of which are listed in the Qualitative Analysis Notes on page 11. (i) Choose reagents that will allow you to identify one of the cations. Carry out suitable tests using these reagents and record your results in the space below. II III IV One of the cations in FA 6 is.UCLES 2014 9701/31/M/J/14 [Turn over<br /> (ii) Carry out the following tests to identify the two anions present in FA 6. test observations PMT To a 1 cm depth of FA 6 in a test-tube add a 1 cm depth of aqueous silver nitrate, then add aqueous ammonia. To a 1 cm depth of FA 6 in a test-tube add a 1 cm depth of aqueous barium chloride (or aqueous barium nitrate), then add dilute nitric acid. The anions in FA 6 areand. [9] VI VII VIII IXUCLES 2014 9701/31/M/J/14<br /> (b) FA 7 is an acidi ed solution of iron(II) sulfate, FeSO4(aq). Carry out the following tests and record your observations. test observations (i) To a 1 cm depth of FA 7 in a test-tube add aqueous sodium hydroxide and leave for a few minutes. (ii) To a 1 cm depth of FA 7 in a boiling tube add a 1 cm depth of dilute sulfuric acid followed by a 1 cm depth of 20 vol hydrogen peroxide. Stir the mixture, then (iii) pour a 1 cm depth of the mixture into a clean boiling tube and add a 3 cm depth of aqueous sodium hydroxide. PMT II III IV VI (iv) What type of reaction takes place in (ii)?(v) Explain your observations in (iii).[6] [Total: 15]UCLES 2014 9701/31/M/J/14 [Turn over<br />

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