Centre Number Candidate Number For Examiner s Use Surname Other Names Candidate Signature Examiner s Initials AQA Level 1/2 Certificate Higher Tier June 2015 Science: Double Award Chemistry Paper 1H Thursday 14 May 2015 9.00 am to 10.00 am 8404/C/1H H Question 1 2 3 4 5 TOTAL Mark For this paper you must have: a ruler a calculator the periodic table (enclosed). Time allowed 1 hour Instructions Use black ink or black ball-point pen. Fill in the es at the top of this page. Answer all questions. You must answer the questions in the spaces provided. around each page or on blank pages. Do all rough work in this book. Cross through any work you do not want to be marked. Information The marks for questions are shown in brackets. The maximum mark for this paper is 60. You are expected to use a calculator where appropriate. You are reminded of the need for good English and clear presentation in your answers. Advice In all calculations, show clearly how you work out your answer. (JUN158404C1H01) P83354/Jun15/E5 8404/C/1H
2 Answer all questions in the spaces provided. 1 This question is about salts. 1 (a) Magnesium carbonate reacts with dilute sulfuric acid to produce magnesium sulfate solution, as shown in Figure 1. Figure 1 Magnesium carbonate Dilute sulfuric acid 1 (a) (i) Complete the word equation.... magnesium sulfuric magnesium þ fi þ carbonate acid sulfate... þ... (02)
3 1 (a) (ii) Magnesium carbonate is insoluble. Magnesium sulfate is soluble. Describe how you would make crystals of magnesium sulfate from magnesium carbonate and dilute sulfuric acid. [5 marks] Question 1 continues on the next page Turn over s (03)
4 1 (b) Table 1 shows information about the solubility of salts. Table 1 Solubility of salts All sodium and potassium salts are soluble. All nitrates are soluble. All sulfates are soluble, except barium sulfate and lead sulfate. All chlorides are soluble, except lead chloride and silver chloride. 1 (b) (i) A precipitate is produced when solutions of sodium chloride and lead nitrate are mixed. Name the precipitate and name the solution produced. Use the information in Table 1 to help you. Precipitate... Solution... 1 (b) (ii) Silver chloride is an insoluble salt. Use Table 1 to name two salt solutions that could be reacted to produce silver chloride. Salt solution 1... Salt solution 2... 1 (b) (iii) Silver chloride and silver iodide are insoluble salts. How can you tell the difference between silver chloride and silver iodide just by looking at the two solids? 13 (04)
5 Turn over for the next question DO NOT WRITE ON THIS PAGE ANSWER IN THE SPACES PROVIDED Turn over s (05)
6 2 This question is about cracking and burning. 2 (a) Cracking breaks down hydrocarbon molecules into smaller hydrocarbon molecules. 2 (a) (i) Give the conditions needed for cracking. 2 (a) (ii) What type of reaction is cracking? Tick (3) one. [1 mark] Combustion Electrolysis Thermal decomposition 2 (b) Octane is a hydrocarbon. A student cracked octane. octane fi smaller alkane þ alkene The student collected the products in the apparatus shown in Figure 2. Figure 2 Products from cracking octane Alkane Alkene Water (06)
7 2 (b) (i) An alkane collected on top of the water. Suggest two reasons why the alkane collected on top of the water. 2 (b) (ii) The student added bromine water to the alkene produced. State the colour of the bromine water before and after the reaction with the alkene. Colour before... Colour after... 2 (b) (iii) State one different use for each product. Use of alkane... Use of alkene... 2 (c) The student burned octane in a limited supply of air. One product was carbon dioxide. Name three other products. [3 marks] 1... 2... 3... 12 Turn over s (07)
8 There are no questions printed on this page DO NOT WRITE ON THIS PAGE ANSWER IN THE SPACES PROVIDED (08)
9 3 This question is about boiling points. 3 (a) Describe what happens to the particles when a liquid boils. You should answer in terms of energy and arrangement of particles. [4 marks] Question 3 continues on the next page Turn over s (09)
10 3 (b) Table 2 shows the boiling points of some Group 0 elements. Table 2 Element Helium Neon Argon Boiling point in o C 270 246 186 Krypton Xenon 108 3 (b) (i) Draw the bars on the grid in Figure 3 to show the boiling points of neon and argon. The bars for helium and xenon have been drawn for you. You should complete the scale on the y axis. [3 marks] Figure 3 0 Element Helium Neon Argon Krypton Xenon 50 Boiling point of element in C (10)
11 3 (b) (ii) Suggest why a line graph is not a suitable way of showing the results. [1 mark] 3 (b) (iii) Predict the boiling point of krypton. [1 mark] Boiling point ¼... C 3 (b) (iv) A scientist measured the boiling point of radon three times. His results are shown in Table 3. Table 3 Reading 1 Reading 2 Reading 3 Boiling point of radon in C 60 63 61 Calculate the mean boiling point of radon. Give your answer to the correct number of significant figures. Mean boiling point of radon ¼... C 11 Turn over for the next question Turn over s (11)
12 4 Potassium bromide is an ionic compound. 4 (a) A potassium atom has one electron in its outer shell. Potassium reacts with bromine to produce potassium bromide. Explain how and why electron transfer occurs in the reaction. [3 marks] 4 (b) Explain why potassium bromide has a high melting point. [3 marks] (12)
13 4 (c) A teacher used the apparatus in Figure 4 to electrolyse molten potassium bromide. She heated the crucible strongly. The lamp glowed when the potassium bromide was molten. Figure 4 d.c. power supply Lamp Crucible + Molten potassium bromide Heat strongly 4 (c) (i) Explain, in terms of particles, why a current flowed when the potassium bromide was molten. 4 (c) (ii) Describe and explain how potassium is produced at the negative electrode (cathode). [3 marks] 11 Turn over s (13)
14 5 This question is about sodium hydroxide and chlorine. 5 (a) Sodium hydroxide is a soluble base. 5 (a) (i) Suggest a ph value for a solution of sodium hydroxide. [1 mark]... 5 (a) (ii) Give the chemical term for a soluble base. [1 mark]... 5 (a) (iii) Give the formula of the hydroxide ion. [1 mark]... 5 (b) Two chlorine atoms share a pair of electrons to produce a molecule. 5 (b) (i) On Figure 5, draw a dot-and-cross diagram to represent a molecule of chlorine (Cl 2 ). You should show only the electrons in the outer shell of each atom. Figure 5 (14)
15 5 (b) (ii) Explain why chlorine is a gas at room temperature. [3 marks] 5 (c) Chlorine reacts, in different ways, with cold sodium hydroxide solution and warm sodium hydroxide solution. 5 (c) (i) The equation shows the reaction between chlorine and warm sodium hydroxide solution. Balance the equation. [1 mark] ::::::::::Cl 2 þ 6NaOH fi ::::::::::NaCl þ NaClO 3 þ ::::::::::H 2 O Question 5 continues on the next page Turn over s (15)
16 5 (c) (ii) Chlorine reacts with cold sodium hydroxide solution to produce NaClO Cl 2 þ 2NaOH fi NaCl þ NaClO þ H 2 O Calculate the mass of sodium hydroxide needed to produce 2.0 g of NaClO [4 marks] Relative atomic masses (A r ): H ¼ 1; O ¼ 16; Na ¼ 23; Cl ¼ 35.5 Mass of sodium hydroxide ¼... g 13 END OF QUESTIONS Copyright ª 2015 AQA and its licensors. All rights reserved. (16)