Edexcel Jan 2011 Paper 6 Q1

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PMT Answer ALL the questions. Write your answers in the spaces provided. 1 Compound X is a coloured hydrated salt, containing two cations and one anion, which dissolves in water to give a coloured solution. (a) What can you infer from the fact that compound X is coloured? (1) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . (b) Compound X contains potassium ions. State what you would see when a flame test is performed on X. (1) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . (c) The following tests are performed on an aqueous solution of X. Complete the Inference(s) column in the following table. Test Observation(s) Inference(s) (i) (ii) Acidify with hydrochloric acid; add barium chloride solution. Add sodium hydroxide solution until in excess. White precipitate Formula of the white precipitate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Grey-green precipitate which is soluble in excess sodium hydroxide to give a deep green solution Formula of the grey-green precipitate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Formula of the deep green ion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . (iii) Make alkaline Yellow solution Formula of the yellow ion with sodium hydroxide solution; add hydrogen peroxide solution and boil. Acidify the solution from (iii) with dilute hydrochloric acid. Add ethanol to the product from (iv) and distil off organic product Y as it is formed. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Orange solution Formula of the orange ion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Orange solution turns green Formula of the green ion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . *N37955A0212* (iv) (v) (1) (1) (1) (1) (1) (1)<br /> PMT (d) Compound X contains z moles of water of crystallization per mole of compound. On the basis of your results, complete the formula for compound X.. zH2O (e) The organic product Y from test (c)(v) is an aldehyde. It was tested as shown in the table below. State the observations that you would make. Test Observation(s) (i) (ii) Addition of 2,4-dinitrophenylhydrazine solution (Bradys reagent). Addition of Tollens reagent (ammoniacal silver nitrate solution). (1) (1) (1) (Total for Question 1 = 11 marks) *N37955A0312* Turn over<br />

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