CIE Jun 2017 v5 Paper 3 Q2

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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 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) FA 4 and FA 5 are aqueous solutions. Each solution contains two different cations and the sulfate anion. (i) Carry out the following tests and record your observations. observations FA 4 FA 5 test To a 1 cm depth of solution in a boiling tube, add aqueous sodium hydroxide, then warm the tube carefully. To a 1 cm depth of solution in a test-tube, add aqueous ammonia. (ii) Identify as many as possible of the cations in FA 4 and FA 5. FA 4 contains the cation(s). FA 5 contains the cation(s). [7]UCLES 2017 9701/35/M/J/17<br /> PMT (b) FA 6 is a salt containing either the sulfate anion or sulfite anion. You will first make a solution of FA 6.Rinse one of the 100 cm3 beakers with distilled water. Place all the sample of FA 6 into the beaker and add approximately 40 cm3 of distilled water. Stir the mixture until the solid has dissolved. Select reagent(s) and carry out tests to identify the anion in FA 6. Record your results in the space below. The formula of the anion in FA 6 is. [3] (c) FA 7 is a solution containing one cation and the sulfate anion. FA 8 is a solution containing the sodium cation and one of the anions from those listed in the Qualitative Analysis Notes. (i) Carry out the following tests to determine the formulae of FA 7 and FA 8. observations test To a 2 cm depth of FA 7 in a test-tube, add a 2 cm strip of magnesium. To a 1 cm depth of FA 7 in a test-tube add a 1 cm depth of FA 8 and shake the tube. (ii) The formula of FA 7 is. The formula of FA 8 is. (iii) Give the ionic equation for the reaction that takes place when magnesium is added to FA 7. Include state symbols.[6]UCLES 2017 9701/35/M/J/17 [Total: 16] [Turn over<br />

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