* * Cambridge International Examinations Cambridge Ordinary Level. CHEMISTRY 5070/11 Paper 1 Multiple Choice October/November 2015.

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1 * * ambridge International Examinations ambridge Ordinary Level EMISTRY 5070/11 Paper 1 Multiple hoice October/November 2015 Additional Materials: Multiple hoice Answer Sheet Soft clean eraser Soft pencil (type or recommended) 1 hour READ TESE INSTRUTIONS FIRST Write in soft pencil. Do not use staples, paper clips, glue or correction fluid. Write your name, entre number and candidate number on the Answer Sheet in the spaces provided unless this has been done for you. DO NOT WRITE IN ANY ARODES. There are forty questions on this paper. Answer all questions. For each question there are four possible answers A,, and D. hoose the one you consider correct and record your choice in soft pencil on the separate Answer Sheet. Read the instructions on the Answer Sheet very carefully. Each correct answer will score one mark. A mark will not be deducted for a wrong answer. Any rough working should be done in this booklet. A copy of the Periodic Table is printed on page 16. Electronic calculators may be used. This document consists of 14 printed pages and 2 blank pages. I15 11_5070_11/4RP ULES 2015 [Turn over

2 1 Which process is used in the preparation of soluble salts? 2 A D electrolysis evaporation melting precipitation 2 Which positive ions are present in aqueous copper(ii) sulfate? A D copper ions only copper ions and hydrogen ions sulfate ions only sulfate ions and hydroxide ions 3 In a titration between an acid (in the burette) and an alkali, you may need to re-use the same titration flask. Which is the best procedure for rinsing the flask? A D Rinse with distilled water and then with the alkali. Rinse with tap water and then with distilled water. Rinse with tap water and then with the acid. Rinse with the alkali. 4 Two containers, one of methane and one of butane, are placed at the same distance from a naked flame. oth gases are released at the same time. The methane gas reaches the flame and catches fire before the butane gas reaches the flame. Which statement explains this? A D Each methane molecule has a higher proportion of hydrogen than each butane molecule. Methane does not have isomers, butane does have isomers. Methane has a higher boiling point than butane. Methane molecules have a smaller mass than butane molecules. ULES /11/O/N/15

3 3 5 Metal X oxidises in air. The formula of the oxide is XO. X displaces zinc from aqueous zinc nitrate. Which could be X? A D aluminium lead magnesium sodium 6 Which is a compound? A D air carbon oxygen steam 7 ow is a calcium ion, a 2+, formed from a calcium atom? A D by gaining two electrons by gaining two protons by losing two electrons by losing two protons 8 An oxygen atom contains 8 electrons, 8 protons and 10 neutrons. What is the nucleon number of this atom? A D 18 9 A molecule of sulfuric acid has the structural formula shown. O O S O O ow many electrons are involved in forming all the covalent bonds in one molecule? A D 16 ULES /11/O/N/15 [Turn over

4 10 A metal consists of a lattice of positive ions in a sea of electrons. 4 What happens to the electrons and positive ions in a metal wire when an electric current is passed through it? electrons positive ions A replaced by new electrons replaced by new ions replaced by new electrons unchanged unchanged replaced by new ions D unchanged unchanged 11 The equation shown represents the neutralisation of aqueous sodium hydroxide with dilute sulfuric acid. 2NaO(aq) + 2 SO 4 (aq) Na 2 SO 4 (aq) O(l) ow much sulfuric acid is required to neutralise 100 cm 3 of 1.0 mol / dm 3 NaO? A D 50 cm 3 of 2.0 mol / dm 3 sulfuric acid 100 cm 3 of 1.0 mol / dm 3 sulfuric acid 25 cm 3 of 0.5 mol / dm 3 sulfuric acid 50 cm 3 of 1.0 mol / dm 3 sulfuric acid 12 Which change in conditions increases the energy of particles in a reaction? A D increase in concentration increase in pressure increase in temperature presence of a catalyst 13 Which change is endothermic? A D 4 (g) + 2O 2 (g) O 2 (g) O(l) (g) + l (g) l (g) 2 O(g) 2(g) + O(g) 2 O(l) 2 O(s) ULES /11/O/N/15

5 5 14 The enthalpy changes when methane, butane and octane are burned completely in oxygen are shown below. enthalpy change (kj / mol) methane, butane, octane, Which are the enthalpy changes when propane and pentane are burned completely in oxygen? propane, 3 8 (kj / mol) pentane, 5 12 (kj / mol) A D In the ionic solid zinc phosphide, Zn 3 P 2, what is the formula of the phosphide ion? A P 3 P 3+ P 4 D P 2+ ULES /11/O/N/15 [Turn over

6 6 16 Iron is produced in the blast furnace. waste gases raw materials hot air slag molten iron Which statement about this process is correct? A D arbon is oxidised to carbon dioxide. arbon monoxide is produced by the thermal decomposition of calcium carbonate. aematite is reduced by calcium carbonate. Impurities are removed by the hot air blast. 17 The energy profile diagram for a reaction is shown. 3 energy 2 products 1 reactants progress of reaction Which statement is correct? A The activation energy of the reaction is ( 3 1 ). The activation energy of the reaction is ( 3 2 ). is ( 1 2 ). D is ( 1 3 ). ULES /11/O/N/15

7 18 In which reaction is nitric acid acting as an oxidising agent? 7 A u + 4NO 3 u(no 3 ) O + 2NO 2 uo + 2NO 3 u(no 3 ) O Na 2 O 3 + 2NO 3 2NaNO O + O 2 D NaO + NO 3 NaNO O 19 Which occurs during the electrolysis of dilute sulfuric acid? A ydrogen and oxygen are formed in the ratio two volumes of oxygen to one volume of hydrogen. D ydrogen is formed at the positive electrode. Oxide ions are oxidised to oxygen. The dilute sulfuric acid becomes more concentrated. 20 Methanol is made in industry by a reaction between carbon monoxide and hydrogen. O(g) (g) 3 O(g) = 90 kj / mol The process is usually carried out at a temperature of 400. Which row correctly shows the effect on both the position of the equilibrium and on the rate of the reaction of increasing the temperature to above 400? position of equilibrium rate of reaction A moves to left decreases moves to left increases moves to right decreases D moves to right increases 21 Which statement about graphite is not correct? A D It burns to form carbon dioxide. It is a carbon compound. It is a giant molecular substance. It is used as a lubricant. ULES /11/O/N/15 [Turn over

8 22 Ammonium nitrate, N 4 NO 3, is an artificial fertiliser produced from ammonia. What is an advantage of using ammonium nitrate as a fertiliser? 8 A D It contains a large percentage by mass of nitrogen. It gives off ammonia gas. Nitrates are insoluble. Nitrates can cause eutrophication. 23 Four metals and hydrogen are arranged in order of decreasing reactivity. potassium aluminium zinc hydrogen copper decrease in reactivity Which statement about these elements is correct? A D Aluminium is formed when aluminium oxide is heated with hydrogen. opper displaces zinc from zinc sulfate solution. opper is formed when copper(ii) oxide is heated with hydrogen. When added to water, aluminium forms positive ions more readily than potassium. 24 Which pair of substances reacts to form a salt and water only? A D aqueous sodium chloride and aqueous silver nitrate aqueous sodium hydroxide and dilute ethanoic acid aqueous sodium carbonate and dilute sulfuric acid zinc and dilute hydrochloric acid 25 An element is burned in an excess of oxygen. Which statement about the oxide formed is always correct? A D The mass of oxide formed is greater than the mass of element burned. The oxide formed is a crystalline solid. The oxide formed is soluble in water. The oxide formed is white in colour. ULES /11/O/N/15

9 26 Which reaction does not involve neutralisation? 9 A D 2 SO 4 (aq) + 2N 3 (aq) (N 4 ) 2 SO 4 (aq) 2 SO 4 (aq) + al 2(aq) aso 4 (s) + 2l (aq) 2 SO 4 (aq) + uo(s) uso 4 (aq) + 2 O(l) 2 SO 4 (aq) + 2NaO(aq) Na 2 SO 4 (aq) O(l) 27 Which element described in the table is a transition metal? number of oxidation states coloured compounds melting point density A one no high low two no low high two yes high high D two yes low low 28 Three different elements react by losing electrons. The ions formed all have the electronic configuration 2,8. Which statement about these elements is correct? A D They are in the same group. They are in the same period. They are noble gases. They are transition elements. 29 An alloy of aluminium is used in the construction of aircraft. Why is pure aluminium never used? A D Pure aluminium cannot be manufactured. Pure aluminium conducts electricity. Pure aluminium is less dense than its alloys. Pure aluminium is too malleable. ULES /11/O/N/15 [Turn over

10 30 What happens when a strip of silver is immersed in an aqueous solution of copper(ii) sulfate? 10 A D ubbles of gas will appear. No reaction occurs. Pink copper will be deposited on the silver strip. The silver strip will start to dissolve. 31 The flow chart shows how impure water can be treated to produce drinkable water. impure water pass through large-sized gravel pass through small-sized gravel pass through carbon pass chlorine through it drinkable water What is not removed from the water by this process? A D clay particles microbes nitrates odours 32 Which property of a liquid ester can be used to check its purity before use as a food flavouring? A D boiling point colour smell solubility in water 33 Which alcohol will, on oxidation, produce 3 2 O 2? A D 3 O 3 2 O O O O ULES /11/O/N/15

11 11 34 The diagram shows the structure of an organic acid. O O Which row is correct? name of acid reacts with aqueous sodium carbonate to produce carbon dioxide A butanoic acid no butanoic acid yes propanoic acid no D propanoic acid yes 35 A carbohydrate such as starch can be represented as shown. What is X? X X X X A D carbon hydrogen nitrogen oxygen ULES /11/O/N/15 [Turn over

12 12 36 P is a polymer that has six carbon atoms in each of the monomers from which it was formed, is not a polyester, was formed using condensation polymerisation. What is the partial structure of P? A O O O O ( 2 ) 4 O ( 2 ) 6 O ( 2 ) 6 N ( 2 ) 6 N D O O ( 2 ) 4 N ( 2 ) 6 N 37 What are the products of photosynthesis? A D carbon dioxide and oxygen carbon dioxide and water glucose and water glucose and oxygen ULES /11/O/N/15

13 38 Which diagram shows the structure of an alloy? 13 A D 39 ydrogen and nitrogen react to form ammonia. Which statement is correct? N N 3 A D Ammonia is made in industry by the ontact process. Ammonia is used in industry to make hydrogen and nitrogen. ydrogen, for the forward reaction, is obtained from cracking oil. Weed killers are manufactured from ammonia. 40 Which statement about the hydrocarbon 2 4 is not correct? A D It contains a double bond. It decolourises bromine water. It forms a condensation polymer. It forms an alcohol when reacted with steam. ULES /11/O/N/15

14 14 LANK PAGE ULES /11/O/N/15

15 15 LANK PAGE ULES /11/O/N/15

16 16 DATA SEET The Periodic Table of the Elements Group I II III IV V VI VII e ydrogen elium Li e N O F Ne Lithium eryllium oron arbon Nitrogen Oxygen Fluorine Neon Na Mg Al Si P S l Ar Sodium Magnesium Aluminium Silicon Phosphorus Sulfur hlorine Argon K a Sc Ti V r Mn Fe o Ni u Zn Ga Ge As Se r Kr Potassium alcium Scandium Titanium Vanadium hromium Manganese Iron obalt Nickel opper Zinc Gallium Germanium Arsenic Selenium romine Krypton Rb Sr Y Zr Nb Mo Tc Ru Rh Pd Ag d In Sn Sb Te Rubidium Strontium Yttrium Zirconium Niobium Molybdenum Technetium Ruthenium Rhodium Palladium Silver admium Indium Tin Antimony Tellurium Iodine Xenon I Xe s a La f Ta W Re Os Ir Pt Au g Tl Pb i Po At Rn aesium arium Lanthanum afnium Tantalum Tungsten Rhenium Osmium Iridium Platinum Gold Mercury Thallium Lead ismuth Polonium Astatine Radon * Fr Ra Ac Francium Radium Actinium *58-71 Lanthanoid series Actinoid series Key b a X a = relative atomic mass X = atomic symbol b = proton (atomic) number e erium 232 Th Thorium 141 Pr Praseodymium 59 Pa Protactinium Nd Neodymium U Uranium Pm Promethium Np Neptunium Sm Samarium Pu Plutonium Eu Europium Am Americium Gd Gadolinium m urium Tb Terbium k erkelium Dy Dysprosium f alifornium o olmium Es Einsteinium Er Erbium Fm Fermium Tm Thulium Md Mendelevium Yb Ytterbium No Nobelium Lu Lutetium Lr Lawrencium 103 The volume of one mole of any gas is 24 dm 3 at room temperature and pressure (r.t.p.). To avoid the issue of disclosure of answer-related information to candidates, all copyright acknowledgements are reproduced online in the ambridge International Examinations opyright Acknowledgements ooklet. This is produced for each series of examinations and is freely available to download at after the live examination series. ULES /11/O/N/15

17 ambridge International Examinations ambridge Ordinary Level EMISTRY 5070/12 Paper 1 Multiple hoice October/November 2015 Additional Materials: READ TESE INSTRUTIONS FIRST Multiple hoice Answer Sheet Soft clean eraser Soft pencil (type or recommended) 1 hour Write in soft pencil. Do not use staples, paper clips, glue or correction fluid. Write your name, entre number and candidate number on the Answer Sheet in the spaces provided unless this has been done for you. DO NOT WRITE IN ANY ARODES. There are forty questions on this paper. Answer all questions. For each question there are four possible answers A,, and D. hoose the one you consider correct and record your choice in soft pencil on the separate Answer Sheet. Read the instructions on the Answer Sheet very carefully. Each correct answer will score one mark. A mark will not be deducted for a wrong answer. Any rough working should be done in this booklet. A copy of the Periodic Table is printed on page 16. Electronic calculators may be used. This document consists of 15 printed pages and 1 blank page. I15 11_5070_12_A3/FP ULES 2015 [Turn over

18 1 The diagram shows the fractional distillation of an aqueous solution of ethanol. 2 water out cold water in ethanol ethanol and water heat Which statement explains why ethanol is collected as the distillate? A D Ethanol has a higher boiling point than water. Ethanol has a higher melting point than water. Ethanol has a lower boiling point than water. Ethanol has a lower melting point than water. 2 In a titration between an acid (in the burette) and an alkali, you may need to re-use the same titration flask. Which is the best procedure for rinsing the flask? A D Rinse with distilled water and then with the alkali. Rinse with tap water and then with distilled water. Rinse with tap water and then with the acid. Rinse with the alkali. ULES /12/O/N/15

19 3 3 Which statements are correct? 1 The volume of a gas at constant pressure increases as the temperature increases. 2 The rate of diffusion of a gas increases as the temperature increases. 3 The pressure of a gas at constant volume decreases as the temperature increases. A 1 and 2 only 1 and 3 only 2 and 3 only D 1, 2 and 3 4 A colourless solution is known to contain a sodium salt. Tests were carried out to determine the identity of the anion in the solution. test observation dilute hydrochloric acid dilute nitric acid followed by aqueous silver nitrate dilute nitric acid followed by aqueous barium nitrate no reaction no precipitate no precipitate Which anion could the solution contain? A D carbonate chloride nitrate sulfate 5 Which physical changes are both exothermic? A D condensation and evaporation evaporation and melting freezing and condensation melting and freezing ULES /12/O/N/15 [Turn over

20 4 6 The following data may refer to the atom or to the ion of the same element. electronic configuration 2,8,8 nucleon number 40 proton number 20 Which element is described by these data? A D argon calcium chlorine neon 7 A molecule of sulfuric acid has the structural formula shown. O O S O O ow many electrons are involved in forming all the covalent bonds in one molecule? A D 16 8 A metal consists of a lattice of positive ions in a sea of electrons. What happens to the electrons and positive ions in a metal wire when an electric current is passed through it? electrons positive ions A replaced by new electrons replaced by new ions replaced by new electrons unchanged unchanged replaced by new ions D unchanged unchanged ULES /12/O/N/15

21 9 The apparatus shown is set up to plate a steel key with copper. 5 + copper steel key aqueous copper(ii) sulfate The key does not get coated with copper. Which change needs to be made to plate the key? A D Increase the concentration of the aqueous copper(ii) sulfate. Increase the voltage. Replace the solution with dilute sulfuric acid. Reverse the electrical connections. 10 What is the number of moles of hydrogen atoms in 3.2 g of methane? A D The formula of the gas ozone is O 3. What is the volume of 48 g of ozone at r.t.p.? A 16 dm 3 24 dm 3 36 dm 3 D 72 dm 3 12 Which substance, when added to pure water, will produce a solution which conducts electricity? A D calcium chloride graphite iron sugar ULES /12/O/N/15 [Turn over

22 13 Two gases, X and Y, react together to form a gas Z, as shown. 6 X(g) + 3Y(g) 2Z(g) = 92 kj / mol Which change in condition will both increase the rate of reaction and increase the equilibrium yield of Z? A D decrease concentration of X increase pressure increase temperature use a catalyst 14 A solution of sodium carbonate was added to tap water. A white precipitate formed. Which ion present in the tap water caused the precipitate to form? A D chloride magnesium potassium sulfate 15 In which reaction is nitric acid acting as an oxidising agent? A u + 4NO 3 u(no 3 ) O + 2NO 2 uo + 2NO 3 u(no 3 ) O Na 2 O 3 + 2NO 3 2NaNO O + O 2 D NaO + NO 3 NaNO O 16 Which reaction does not involve neutralisation? A D 2 SO 4 (aq) + 2N 3 (aq) (N 4 ) 2 SO 4 (aq) 2 SO 4 (aq) + al 2(aq) aso 4 (s) + 2l (aq) 2 SO 4 (aq) + uo(s) uso 4 (aq) + 2 O(l) 2 SO 4 (aq) + 2NaO(aq) Na 2 SO 4 (aq) O(l) ULES /12/O/N/15

23 17 Which pair of substances reacts to form a salt and water only? 7 A D aqueous sodium chloride and aqueous silver nitrate aqueous sodium hydroxide and dilute ethanoic acid aqueous sodium carbonate and dilute sulfuric acid zinc and dilute hydrochloric acid 18 Iron is obtained in the blast furnace from the ore haematite. Which reaction takes place in the blast furnace? A D alcium carbonate is used to remove acidic impurities. oke is reduced to carbon dioxide. aematite is oxidised by carbon monoxide. aematite undergoes thermal decomposition. 19 Aluminium is manufactured from aluminium oxide by electrolysis. The compound cryolite is used in this process. Which statement about cryolite is correct? A D It is the common name for aluminium oxide. It is used to dissolve the aluminium oxide. It is used to make the positive electrode. It is used to make the negative electrode. 20 An element is burned in an excess of oxygen. Which statement about the oxide formed is always correct? A D The mass of oxide formed is greater than the mass of element burned. The oxide formed is a crystalline solid. The oxide formed is soluble in water. The oxide formed is white in colour. 21 Which statement about the Periodic Table is correct? A D Elements are arranged in order of decreasing proton number. Group number is the number of electron shells in atoms of the elements in the group. Group numbers can be used to predict the charges of ions. Metallic character increases left to right across a period. ULES /12/O/N/15 [Turn over

24 22 Which negative ions are present in aqueous copper(ii) sulfate? 8 A D copper(ii) ions and hydrogen ions copper(ii) ions only sulfate ions and hydroxide ions sulfate ions only 23 The reaction shown for the aber process can reach equilibrium. N 2 (g) (g) 2N 3 (g) Which row shows the gases present at equilibrium? nitrogen hydrogen ammonia A no no yes no yes yes yes no yes D yes yes yes 24 Which statement about graphite is not correct? A D It burns to form carbon dioxide. It is a carbon compound. It is a giant molecular substance. It is used as a lubricant. ULES /12/O/N/15

25 25 The energy profile diagram for a reaction is shown. 9 3 energy 2 products 1 reactants progress of reaction Which statement is correct? A The activation energy of the reaction is ( 3 1 ). The activation energy of the reaction is ( 3 2 ). is ( 1 2 ). D is ( 1 3 ). 26 The Periodic Table shows the positions of elements A,, and D. These are not the usual symbols of these elements. Which element has a high melting point and can be used as a catalyst? I II III IV V VI VII 0 A D 27 Which of the statements about iron and steel is not correct? A D oth iron and steel conduct electricity. Mild steel is used in car bodies. Pure iron is formed in the blast furnace. The addition of carbon to mild steel makes it stronger. ULES /12/O/N/15 [Turn over

26 10 28 Some reactions are shown. 1 2SO 2 + O 2 2SO O 2 5 O Which of these reactions use a catalyst when carried out industrially? A 1 only 1 and 2 only 2 and 3 only D 1, 2 and 3 29 Which change is endothermic? A D 4 (g) + 2O 2 (g) O 2 (g) O(l) (g) + l (g) l (g) 2 O(g) 2(g) + O(g) 2 O(l) 2 O(s) 30 Which two elements are the major constituents of brass? A r and As u and Sn u and Zn D Sn and Zn 31 Two statements about copper are given. 1 opper is below hydrogen in the reactivity series. 2 opper can be obtained by heating its oxide with carbon. Which statements are correct? A both 1 and 2 1 only 2 only D neither 1 nor 2 32 What is the order of reactivity of the halogens? most reactive least reactive A bromine chlorine iodine chlorine bromine iodine iodine bromine chlorine D iodine chlorine bromine ULES /12/O/N/15

27 33 The flow chart shows how impure water can be treated to produce drinkable water. 11 impure water pass through large-sized gravel pass through small-sized gravel pass through carbon pass chlorine through it drinkable water What is not removed from the water by this process? A D clay particles microbes nitrates odours 34 Which diagram shows the isomer of butane? A D ULES /12/O/N/15 [Turn over

28 35 The diagram shows the structure of a monomer used to make a polymer What is the structure of the polymer? A D Which property of a liquid ester can be used to check its purity before use as a food flavouring? A D boiling point colour smell solubility in water ULES /12/O/N/15

29 37 The structures of three hydrocarbons from the same homologous series are shown. 13 W X Y Which statement is correct? A All three molecules are unsaturated hydrocarbons. All three molecules have the same empirical formula. W has the lowest boiling point. D X is an isomer of Y. 38 ow many of the following statements about ethanol are correct? 1 molecular formula is 2 6 O 2 manufactured from ethane and steam 3 oxidises to ethanoic acid 4 produced by the fermentation of glucose 5 used as a fuel 6 used as a solvent A D 6 39 Proteins and nylon both possess the same amide linkages. Which arrangement of atoms represents an amide linkage? A D O O O O N N O O N ULES /12/O/N/15 [Turn over

30 14 40 A carbohydrate such as starch can be represented as shown. X X X X What is X? A D carbon hydrogen nitrogen oxygen ULES /12/O/N/15

31 15 LANK PAGE ULES /12/O/N/15

32 16 DATA SEET The Periodic Table of the Elements Group I II III IV V VI VII ydrogen 2 4 e elium 3 7 Li Lithium 4 9 e eryllium 5 11 oron 6 12 arbon 7 14 N Nitrogen 8 16 O Oxygen 9 19 F Fluorine Ne Neon Na Sodium 24 Mg Magnesium Al Aluminium Si Silicon 31 P Phosphorus S Sulfur l hlorine Ar Argon K Potassium a alcium Sc Scandium Ti Titanium V Vanadium r hromium 55 Mn Manganese Fe Iron o obalt Ni Nickel u opper Zn Zinc Ga Gallium 73 Ge Germanium As Arsenic Se Selenium r romine Kr Krypton Rb Rubidium Sr Strontium Y Yttrium Zr Zirconium Nb Niobium 96 Mo Molybdenum 42 Tc Technetium Ru Ruthenium Rh Rhodium Pd Palladium Ag Silver d admium In Indium Sn Tin Sb Antimony Te Tellurium I Iodine Xe Xenon s aesium Fr Francium a arium 226 Ra Radium 139 La Lanthanum 57 * Ac Actinium f afnium Ta Tantalum W Tungsten Re Rhenium Os Osmium Ir Iridium Pt Platinum Au Gold g Mercury Tl Thallium Pb Lead i ismuth 84 Po Polonium 85 At Astatine 86 Rn Radon *58-71 Lanthanoid series Actinoid series Key b a X a = relative atomic mass X = atomic symbol b = proton (atomic) number e erium 232 Th Thorium 141 Pr Praseodymium 59 Pa Protactinium Nd Neodymium U Uranium Pm Promethium Np Neptunium Sm Samarium Pu Plutonium Eu Europium Am Americium Gd Gadolinium m urium Tb Terbium k erkelium 162 Dy Dysprosium f alifornium o olmium Es Einsteinium Er Erbium Fm Fermium Tm Thulium Md Mendelevium Yb Ytterbium No Nobelium Lu Lutetium Lr Lawrencium 103 The volume of one mole of any gas is 24 dm 3 at room temperature and pressure (r.t.p.). To avoid the issue of disclosure of answer-related information to candidates, all copyright acknowledgements are reproduced online in the ambridge International Examinations opyright Acknowledgements ooklet. This is produced for each series of examinations and is freely available to download at after the live examination series. ULES /12/O/N/15

33 ambridge International Examinations ambridge Ordinary Level * * EMISTRY 5070/21 Paper 2 Theory October/November hour 30 minutes andidates answer on the Question Paper. No Additional Materials are required. READ TESE INSTRUTIONS FIRST Write your entre number, candidate number and name on all the work you hand in. Write in dark blue or black pen. You may use an pencil for any diagrams or graphs. Do not use staples, paper clips, glue or correction fluid. DO NOT WRITE IN ANY ARODES. Section A Answer all questions. Write your answers in the spaces provided in the Question Paper. Section Answer any three questions. Write your answers in the spaces provided in the Question Paper. Electronic calculators may be used. You may lose marks if you do not show your working or if you do not use appropriate units. A copy of the Periodic Table is printed on page 20. At the end of the examination, fasten all your work securely together. The number of marks is given in brackets [ ] at the end of each question or part question. This document consists of 17 printed pages and 3 blank pages. D (LK/SW) 89535/4 ULES 2015 [Turn over

34 2 Section A Answer all the questions in this section in the spaces provided. The total mark for this section is 45. A1 hoose from the following gases to answer the questions below. ammonia argon carbon dioxide chlorine ethane ethene nitrogen nitrogen(ii) oxide oxygen sulfur dioxide Each of these gases can be used once, more than once or not at all. Which gas (a) forms approximately 1% of the air,...[1] (b) bleaches damp litmus paper,...[1] (c) reacts with water to form an alkaline solution,...[1] (d) can undergo polymerisation,...[1] (e) is a compound formed in the atmosphere as a result of lightning activity,...[1] (f) is a diatomic molecule containing a total of 16 electrons?...[1] [Total: 6] ULES /21/O/N/15

35 A2 oal is a mixture of carbon compounds with a small amount of sulfur. A sample of coal is heated in the absence of air using the apparatus shown. powdered coal 3 heat water colourless liquid tar The distillate is a mixture of a colourless liquid and tar. (a) The colourless liquid contains ammonia, N 3. Draw a dot-and-cross diagram for ammonia. Show only the outer shell electrons. (b) The tar contains ethanoic acid. When warmed in the presence of sulfuric acid, ethanoic acid reacts with propanol to form an ester. Name and draw the structure of this ester showing all the atoms and all the bonds. name... structure [2] [2] ULES /21/O/N/15 [Turn over

36 (c) The tar also contains a compound with the following composition. 4 element percentage by mass carbon hydrogen 6.38 oxygen Deduce the empirical formula of this compound. empirical formula...[2] (d) When coal is burned, an acidic gas is produced which decolourises acidified aqueous potassium manganate(vii). This gas contributes to acid rain. (i) Identify this gas and describe how acid rain is formed [2] (ii) Give one adverse effect of acid rain on buildings....[1] (iii) Acid rain can have an adverse effect on respiration. Write an equation to represent the process of respiration....[2] [Total: 11] ULES /21/O/N/15

37 A3 A layer of ozone is present in the stratosphere about 30 km above the Earth s surface. 5 (a) ompounds with formulae such as l 3 F and 2 l F 5 are responsible for the depletion of ozone. (i) Give the general name for these compounds....[1] (ii) Explain, in terms of human health, why it is important that the ozone in the stratosphere does not become too depleted [2] (b) In the stratosphere, ozone, O 3, is broken down to oxygen by photochemical reactions. (i) What is meant by the term photochemical reaction?......[1] (ii) onstruct an equation for the breakdown of ozone molecules to oxygen molecules....[1] (c) Ozone oxidises Fe 2+ ions to Fe 3+ ions. omplete the ionic equation for this reaction.. Fe O 3. Fe O + O 2 [1] [Total: 6] ULES /21/O/N/15 [Turn over

38 6 A4 opper is a metal. (a) Draw a labelled diagram to show the bonding in copper. [2] (b) Explain why metals are malleable [2] (c) opper corrodes slowly in damp air. One of the corrosion products has the formula uo 3.u(O) 2. (i) alculate the percentage by mass of copper in this compound. [2] (ii) ow could you show that uo 3.u(O) 2 contains carbonate ions? [2] ULES /21/O/N/15

39 (d) opper is oxidised by concentrated sulfuric acid. This redox reaction can be represented by equations A and. A u u e SO e 2 2 O + SO 2 Which reaction, A or, is oxidation and which is reduction? Explain your answer [2] [Total: 10] ULES /21/O/N/15 [Turn over

40 A5 A student set up a tube as shown in the diagram. 8 X cotton wool soaked in hydrobromic acid cotton wool soaked in aqueous ammonia oncentrated hydrobromic acid produces fumes of hydrogen bromide. oncentrated aqueous ammonia produces fumes of ammonia. (a) After some time, solid ammonium bromide appeared on the walls of the tube at point X. Use the kinetic particle theory to explain this result [4] (b) A gas syringe is filled with 70 cm 3 of ammonia gas. The pressure on the plunger is increased. The temperature does not change but the volume in the syringe decreases to 60 cm 3. plunger gas syringe 70 cm 3 ammonia 60 cm 3 gas blocked syringe end Use the kinetic particle theory to explain why the volume decreases [1] [Total: 5] ULES /21/O/N/15

41 9 A6 When 1 mole of sodium hydroxide reacts with excess hydrochloric acid, 57.1 kj of energy is released. NaO + l Nal + 2 O (a) alculate the energy released when 12.0 g of sodium hydroxide reacts with excess hydrochloric acid. (b) alculate the volume of mol / dm 3 l which contains 2.19 g of l. [2] [2] (c) Aqueous hydrochloric acid contains chloride ions. Describe a test for chloride ions. test... result...[2] (d) Zinc oxide reacts with both hydrochloric acid and sodium hydroxide. Which term describes this behaviour of zinc oxide?...[1] [Total: 7] ULES /21/O/N/15 [Turn over

42 10 Section Answer three questions from this section in the spaces provided. The total mark for this section is The structures of graphite and boron nitride are shown below. Key = carbon atom Key nitrogen atom boron atom graphite boron nitride (a) Like graphite, boron nitride feels slippery to the touch. Explain, in terms of structure and bonding, why boron nitride feels slippery to the touch [2] (b) An isotope of boron is represented by the symbol Deduce the number of protons and neutrons in this isotope of boron. number of protons... number of neutrons...[1] (c) Explain why graphite has a high melting point [2] ULES /21/O/N/15

43 (d) Dilute sulfuric acid can be electrolysed using graphite electrodes. 11 oxygen hydrogen dilute sulfuric acid graphite electrodes + (i) Graphite is a good electrical conductor. Explain why graphite conducts electricity....[1] (ii) Give another property of graphite that makes it useful as an electrode in this electrolysis....[1] (e) During the electrolysis of dilute sulfuric acid, oxygen is released at the anode (positive electrode) and hydrogen is released at the cathode (negative electrode). (i) omplete the equation for the reaction at the anode. 4O O [1] (ii) onstruct the equation for the reaction at the cathode....[1] (iii) Explain why the volume of hydrogen produced is approximately double that of the oxygen [1] ULES /21/O/N/15 [Total: 10] [Turn over

44 12 8 A sample of g of small pieces of magnesium is added to 20 cm 3 of 0.10 mol / dm 3 hydrochloric acid. Mg(s) + 2l (aq) Mgl 2 (aq) + 2 (g) (a) (i) Show by calculation which reactant is in excess. [3] (ii) What would you observe in this reaction?...[1] ULES /21/O/N/15

45 13 (b) The graph shows how the volume of hydrogen gas produced, at room temperature and pressure, changes with time. 30 volume of hydrogen / cm time / s alculate the total mass of hydrogen formed. mass of hydrogen =... g [2] (c) The experiment is repeated at the same temperature and pressure. The same mass of magnesium is added but magnesium powder is used instead of small pieces. The rate of reaction is faster. Explain why [2] (d) Magnesium reacts with nitrogen when heated. The ionic compound magnesium nitride, Mg 3 N 2, is formed. (i) onstruct the equation, including state symbols, for this reaction....[1] (ii) Deduce the charge on the nitride ion....[1] ULES /21/O/N/15 [Total: 10] [Turn over

46 14 9 The structure of glycolic acid can be represented as shown. O O O (a) Glycolic acid is a solid at room temperature. Describe the arrangement and motion of the molecules in glycolic acid at room temperature. arrangement... motion...[2] (b) Glycolic acid can polymerise with itself to form a polyester called poly(glycolic acid). (i) What type of polymer is a polyester?...[1] (ii) Draw a section of the polymer chain of poly(glycolic acid) showing at least two repeating units. [2] ULES /21/O/N/15

47 15 (c) Glycolic acid is produced by heating methanal, carbon monoxide and water in the presence of a sulfuric acid catalyst. 2 O + O + 2 O methanal 2 (O)OO glycolic acid (i) A sample of 1800 g of methanal reacts with excess carbon monoxide and water. The percentage yield of glycolic acid is 45%. alculate the mass, in grams, of glycolic acid produced. mass of glycolic acid =... g [3] (ii) Glycolic acid is a weak acid. Sulfuric acid is a strong acid. Explain the difference between a strong acid and a weak acid [2] [Total: 10] ULES /21/O/N/15 [Turn over

48 16 10 Methanol is manufactured by reacting carbon monoxide with hydrogen. The forward reaction is exothermic. O(g) (g) 3 O(g) Δ = 91 kj / mol (a) Predict and explain the effect of increasing the pressure on the position of equilibrium. The temperature remains constant [2] (b) Predict and explain the effect of decreasing the temperature on the position of equilibrium. The pressure remains constant [2] (c) The rate of reaction decreases when the temperature is lowered. Explain why [2] (d) The reaction is catalysed by copper. (i) Describe and explain the effect of a catalyst on this reaction [2] (ii) opper is a transition element. Many transition elements are catalysts. Give two other properties of copper that identify it as a transition element [2] [Total: 10] ULES /21/O/N/15

49 17 LANK PAGE ULES /21/O/N/15

50 18 LANK PAGE ULES /21/O/N/15

51 19 LANK PAGE Permission to reproduce items where third-party owned material protected by copyright is included has been sought and cleared where possible. Every reasonable effort has been made by the publisher (ULES) to trace copyright holders, but if any items requiring clearance have unwittingly been included, the publisher will be pleased to make amends at the earliest possible opportunity. To avoid the issue of disclosure of answer-related information to candidates, all copyright acknowledgements are reproduced online in the ambridge International Examinations opyright Acknowledgements ooklet. This is produced for each series of examinations and is freely available to download at after the live examination series. ambridge International Examinations is part of the ambridge Assessment Group. ambridge Assessment is the brand name of University of ambridge Local Examinations Syndicate (ULES), which is itself a department of the University of ambridge. ULES /21/O/N/15

52 20 DATA SEET The Periodic Table of the Elements Group I II III IV V VI VII ydrogen 2 4 e elium 3 7 Li Lithium 4 9 e eryllium 5 11 oron 6 12 arbon 7 14 N Nitrogen 8 16 O Oxygen 9 19 F Fluorine Ne Neon Na Sodium Mg Magnesium Al Aluminium Si Silicon P Phosphorus S Sulfur l hlorine Ar Argon K Potassium a alcium Sc Scandium Ti Titanium V Vanadium r hromium Mn Manganese Fe Iron o obalt Ni Nickel u opper Zn Zinc Ga Gallium Ge Germanium As Arsenic Se Selenium r romine Kr Krypton Rb Rubidium Sr Strontium Y Yttrium Zr Zirconium Nb Niobium 96 Mo Molybdenum Tc Technetium Ru Ruthenium Rh Rhodium Pd Palladium Ag Silver d admium In Indium Sn Tin Sb Antimony Te Tellurium I Iodine Xe Xenon s aesium a arium 139 La Lanthanum 57 * f afnium Ta Tantalum W Tungsten Re Rhenium Os Osmium Ir Iridium Pt Platinum Au Gold g Mercury Tl Thallium Pb Lead i ismuth 84 Po Polonium 85 At Astatine 86 Rn Radon Fr Francium Ra Radium 227 Ac Actinium 89 * Lanthanoid series Actinoid series Key b a X a = relative atomic mass X = atomic symbol b = atomic (proton) number e erium 232 Th Thorium 141 Pr Praseodymium Pa Protactinium Nd Neodymium 238 U Uranium Pm Promethium Sm Samarium Eu Europium Gd Gadolinium Tb Terbium Dy Dysprosium Np Neptunium 94 Pu Plutonium 95 Am Americium 96 m urium 97 k erkelium 98 f alifornium o olmium Es Einsteinium Er Erbium Fm Fermium Tm Thulium Md Mendelevium Yb Ytterbium No Nobelium Lu Lutetium Lr Lawrencium 103 The volume of one mole of any gas is 24dm 3 at room temperature and pressure (r.t.p.). ULES /21/O/N/15

53 ambridge International Examinations ambridge Ordinary Level * * EMISTRY 5070/22 Paper 2 Theory October/November hour 30 minutes andidates answer on the Question Paper. No Additional Materials are required. READ TESE INSTRUTIONS FIRST Write your entre number, candidate number and name on all the work you hand in. Write in dark blue or black pen. You may use an pencil for any diagrams or graphs. Do not use staples, paper clips, glue or correction fluid. DO NOT WRITE IN ANY ARODES. Section A Answer all questions. Write your answers in the spaces provided in the Question Paper. Section Answer any three questions. Write your answers in the spaces provided in the Question Paper. Electronic calculators may be used. You may lose marks if you do not show your working or if you do not use appropriate units. A copy of the Periodic Table is printed on page 20. At the end of the examination, fasten all your work securely together. The number of marks is given in brackets [ ] at the end of each question or part question. This document consists of 20 printed pages. D (LK/SW) /5 R ULES 2015 [Turn over

54 2 Section A Answer all the questions in this section in the spaces provided. The total mark for this section is 45. A1 hoose from the following elements to answer the questions below. aluminium argon carbon copper iodine iron lead magnesium nitrogen oxygen sulfur Each of these elements can be used once, more than once or not at all. Which element (a) has an ion which, in aqueous solution, reacts with aqueous sodium hydroxide to give a red-brown precipitate,...[1] (b) has an atom with an electronic configuration with only five occupied electron shells,...[1] (c) has an oxide which decolourises acidified potassium manganate(vii),...[1] (d) has a sulfate which is insoluble in water,...[1] (e) provides an inert atmosphere for the extraction of reactive metals,...[1] (f) produces ammonia when it is warmed with an aqueous mixture of sodium nitrate and sodium hydroxide?...[1] [Total: 6] ULES /22/O/N/15

55 A2 Plants contain many different types of carbon compounds. (a) arbon compounds are made in plants by photosynthesis. 3 Write the overall equation for photosynthesis and state the conditions required for this process [3] (b) Starch is a polymer found in plants. Starch can be hydrolysed. (i) Give the name of the product formed when starch is hydrolysed....[1] (ii) Give the reagent and conditions needed to hydrolyse starch....[2] ULES /22/O/N/15 [Turn over

56 (c) When wood chips are heated in the absence of air, a colourless distillate is formed. 4 wood chips cold water heat distillate The distillate contains ethanoic acid, esters and other organic compounds. (i) Ethanoic acid reacts with calcium hydroxide to form a salt and water. Give the name and formula of the salt formed. name... formula...[2] (ii) One of the esters in the distillate has the molecular formula, 4 8 O 2. Draw the structure of an ester with this formula, showing all the atoms and all the bonds. [1] ULES /22/O/N/15

57 5 (iii) The distillate also contains a compound with the following composition. element percentage by mass carbon 37.5 hydrogen 12.5 oxygen 50.0 Deduce the empirical formula of this compound. empirical formula...[2] [Total: 11] ULES /22/O/N/15 [Turn over

58 A3 Water for use in the home is treated using carbon and chlorine. (a) Explain the purpose of using carbon and chlorine in water treatment. 6 carbon... chlorine...[2] (b) In some parts of the world, drinking water is purified by desalination. What is meant by the term desalination?...[1] (c) River water may contain pollutants from agricultural sources. These pollutants may cause eutrophication. Give the names of two anions present in fertilisers which contribute to eutrophication.... and... [1] (d) An aqueous solution of barium chloride is added to a sample of water which contains sulfate ions. A white precipitate forms. onstruct an ionic equation, including state symbols, for this reaction....[2] [Total: 6] ULES /22/O/N/15

59 A4 Iron is extracted in a blast furnace. The raw materials required are iron ore, which contains iron(iii) oxide, Fe 2 O 3, limestone, coke (carbon), air. (a) The coke first burns in air to form carbon dioxide. The carbon dioxide is then reduced by coke to produce carbon monoxide. The carbon monoxide reduces the iron(iii) oxide to iron. Write equations for 7 (i) the reduction of carbon dioxide by coke,...[1] (ii) the reduction of iron(iii) oxide to iron by carbon monoxide....[1] (b) Why is limestone added to the blast furnace?...[1] (c) Another ore of iron contains an oxide with the formula Fe 3 O 4. alculate the percentage by mass of iron in Fe 3 O 4. [2] ULES /22/O/N/15 [Turn over

60 8 (d) Iron can be obtained by the electrolysis of an aqueous acidified solution of iron(ii) sulfate. The reactions at the electrodes are given. at the anode (positive electrode): 4O O O + 4e at the cathode (negative electrode): Fe e Fe Which reaction is oxidation and which is reduction? Explain your answer [2] (e) Attaching magnesium strips to the iron hulls of ships can lower their rate of rusting. Explain how the magnesium stops the iron from rusting [2] (f) Aqueous iron(ii) chloride is one of the products formed when iron reacts with hydrochloric acid. onstruct an equation for this reaction....[1] [Total: 10] ULES /22/O/N/15

61 9 A5 (a) Two students set up tubes as shown. tube 1 cotton wool soaked in concentrated hydrochloric acid cotton wool soaked in concentrated hydrobromic acid blue litmus paper tube 2 oncentrated hydrochloric acid produces fumes of hydrogen chloride. oncentrated hydrobromic acid produces fumes of hydrogen bromide. Four minutes after setting up the experiment, the litmus paper in tube 1 turns red. Seven minutes after setting up the experiment, the litmus paper in tube 2 turns red. Use the kinetic particle theory to explain (i) how the gases move through the tubes, [2] (ii) why the gases take different times to reach the litmus paper [1] ULES /22/O/N/15 [Turn over

62 10 (b) A gas syringe is filled with 80 cm 3 of hydrogen chloride gas at 20. The syringe is placed in some hot water at 50. The atmospheric pressure does not change but the volume of the gas in the syringe increases to 88 cm 3. blocked syringe end hydrogen chloride hot water 80 cm cm 3 hydrogen chloride Use the kinetic particle theory to explain why the volume increases [2] [Total: 5] ULES /22/O/N/15

63 11 A6 When one mole of sulfur burns, 247 kj of energy is released. S(s) + O 2 (g) SO 2 (g) (a) alculate the energy released when 9.60 g of sulfur is burnt. (b) When sulfur dioxide is passed through aqueous sodium hydroxide, sodium hydrogensulfite is formed. Sodium hydrogensulfite contains the hydrogensulfite ion, SO 3. onstruct the ionic equation for this reaction....[1] (c) The hydrogensulfite ion is a weaker acid than ethanoic acid. Samples of 0.1 g of magnesium are added separately to 0.1 mol / dm 3 ethanoic acid and 0.1 mol / dm 3 hydrogensulfite ions. Explain why the reaction is faster with ethanoic acid [2] (d) alculate the volume of 0.10 mol / dm 3 sodium hydroxide which contains 3.2 g of sodium hydroxide. [2] volume of aqueous sodium hydroxide =... cm 3 [2] [Total: 7] ULES /22/O/N/15 [Turn over

64 12 Section Answer three questions from this section in the spaces provided. The total mark for this section is The structures of diamond and silicon dioxide are shown. silicon atom oxygen atom diamond silicon dioxide (a) Describe one similarity in the structures of diamond and silicon dioxide....[1] (b) Explain why silicon dioxide has a high melting point [2] (c) Silicon dioxide reacts with hot concentrated sodium hydroxide to form sodium silicate, Na 2 SiO 3. Deduce the formula of the silicate ion....[1] (d) Explain why diamond does not conduct electricity....[1] (e) Graphite is a form of carbon which conducts electricity. Graphite is used as electrodes in electrolysis. What is the meaning of the term electrolysis?......[1] ULES /22/O/N/15

65 13 (f) Aluminium is extracted by the electrolysis of molten aluminium oxide dissolved in cryolite. onstruct the equation for the reaction at (i) the anode (positive electrode),...[1] (ii) the cathode (negative electrode)....[1] (g) An isotope of silicon is represented by the symbol Si. Deduce the number of protons and neutrons in this isotope. number of protons... number of neutrons...[1] (h) Silicon has a relative atomic mass of 28. Define the term relative atomic mass [1] [Total: 10] ULES /22/O/N/15 [Turn over

66 14 8 hlorine reacts with sodium hydroxide. l 2 (g) + 2NaO(aq) Nal (aq) + NalO(aq) + 2 O(l) (a) A volume of 144 cm 3 of chlorine gas, measured at room temperature and pressure, is passed into 38.0 cm 3 of mol / dm 3 sodium hydroxide. Show by calculation which reactant is in excess. (b) hlorine displaces bromine from an aqueous solution of potassium bromide. [3] (i) onstruct the equation for this reaction....[2] (ii) Explain why bromine does not react with aqueous potassium chloride [1] (iii) Give the charge of a chloride ion and its electronic configuration. charge... electronic configuration...[2] (c) Explain why sodium chloride does not conduct electricity when solid but does conduct electricity when molten [2] [Total: 10] ULES /22/O/N/15

67 15 Question 9 begins on page 16. ULES /22/O/N/15 [Turn over

68 16 9 When rubber is heated in the absence of air, a small amount of isoprene is formed. The structure of isoprene is shown. (a) Isoprene is an unsaturated hydrocarbon. Describe a test for an unsaturated hydrocarbon [2] (b) Isoprene is a liquid at 25. Describe the arrangement and motion of the particles in isoprene at [2] (c) Isoprene reacts with sulfur dioxide to form methylsulfolene SO SO 2 isoprene methylsulfolene alculate the maximum mass of methylsulfolene that can be formed from 100 g of isoprene. mass of methylsulfolene =... g [3] ULES /22/O/N/15