JJC H1 CHEM P1 Prelim

JURONG JUNIOR COLLEGE JC 2 PRELIMINARY EXAMINATION Higher 1 CHEMISTRY 8872/01 Paper 1 Multiple Choice 25 August 2009 50 minutes Additional Materials: Multiple Choice Answer Sheet Data Booklet READ THESE INSTRUCTIONS FIRST Write in soft pencil. Do not use staples, paper clips, highlighters, glue or correction fluid. Write your name, class and shade your exam number on the Answer Sheet in the spaces provided. There are thirty questions on this paper. Answer all questions. For each question there are four possible answers A, B, C and D. Choose the one you consider correct and record you 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 Data Booklet is provided. Do not write anything on the Data Booklet. This document consists of 12 printed pages and 1 blank page. [Turn over

SECTION A For each question there are four possible answers, A, B, C and D . Choose the one you consider to be correct. 1. Hydrogen has three isotopes – hydrogen H, 1 1 ; deuterium D, ; tritium T, . H 2 1H 3 1H Which molecule contains the same number of neutrons as HT? A D2 B DT C HD D T2 2. Carbon disulphide vapour burns in oxygen according to the following equation. CS2(g) + 3O2(g)  CO2(g) + 2SO2(g) A sample of 10 cm 3 of carbon disulphide was burnt in 50 cm 3 of oxygen. After measuring the volume of gas remaining, the product was treated with an excess of aqueous sodium hydroxide and the volume of gas measured again. All measurements were made at the same temperature and pressure; under such conditions that carbon disulpide was gaseous. What were the measured volumes? volume of gas after burning/ cm3 volume of gas after adding NaOH(aq)/ cm3 A 30 0 B 30 20 C 50 20 D 50 40 3. Use of the Data Booklet is relevant to this question. The combustion of fossil fuels is a major source of increasing atmospheric carbon dioxide, with a consequential rise in global warming. Another significant contribution to carbon dioxide levels comes from the thermal decomposition of limestone, CaCO 3, in the manufacture of cement and of lime, CaO, for agricultural purposes. Cement works roast 1000 million tonnes of limestone per year and a further 200 million tonnes is roasted in kilns to make lime. What is the total annual mass output of carbon dioxide (in million tonnes) from these two processes? A 440 B 527 C 660 D 880 Page 2 of 12

4. The nickel-cadmium (Ni-Cd) rechargeable battery is based upon the following reaction. Cd + 2NiOOH + 4H2O  Cd(OH)2 + 2Ni(OH)2.H2O What is the oxidation number of nickel at the beginning and at the end of the reaction? beginning end A +1.5 +2 B +2 +3 C +3 +2 D +3 +4 5. Which reagent, when mixed and heated with ammonium sulphate, liberates ammonia? A aqueous bromine B limewater C dilute hydrochloric acid D potassium dichromate(VI) 6. Which pair of elements have bonds of the same type between their atoms in the solid state? A aluminium and phosphorus B chlorine and argon C magnesium and silicon D sulphur and chlorine 7. What is the molecular geometry and the C l-I-Cl bond angle of ICl4  according to Valence Shell Electron Pair Repulsion theory? A square planar, 90° B square pyramidal, 90° C tetrahedral, 109° D trigonal pyramidal, 107° Page 3 of 12

8. In this question, the methyl group, CH3, is represented by Me. Trimethylamine, Me3N, reacts with boron trifluoride, BF 3, to form a compound of formula Me3N.BF3. Assume that Me3N reacts in a similar manner to NH3. How may this reaction be written in terms of the shapes of the reactants and products? A B C D 9. Iodine trichloide, ICl3, is made by reacting iodine with chlorine. I2(s) + Cl2(g)  2ICl(s); ΔH = + 14 kJ mol1 ICl(s) + Cl2(g)  ICl3(s); ΔH =  88 kJ mol1 By using the above date and the following energy cycle, what is the enthalpy change of the formation of solid iodine trichloride? A 60 kJ mol1 B 74 kJ mol1 C 81 kJ mol1 D 162 kJ mol1 ICl3(s) 1 2 I2(s) + 3 2 Cl2(g) ICl(s) + Cl2(g) Page 4 of 12

10. The table shows the enthalpy change of neutralisation per mole of water formed, ΔH, for various acids and bases. acid base ΔH / kJ mol1 hydrochloric acid sodium hydroxide 57.0 P sodium hydroxide 54.0 hydrochloric acid Q 52.0 nitric acid R 57.0 What are P, Q and R? P Q R A ethanoic acid ammonia potassium hydroxide B ethanoic acid sodium hydroxide ammonia C sulphuric acid ammonia potassium hydroxide D sulphuric acid sodium hydroxide ammonia 11. In an industrial process, two gases X and Y react together to form a single gaseous product Z. X(g) + Y(g)  Z(g) The percentage yield of product Z varies according to the pressure and the temperature as shown in the graphs. Which statement about this equilibrium reaction is correct? A Decreasing the temperature decreases the value of the equilibrium constant. B Increasing the pressure decreases the value of the equilibrium constant. C Increasing the pressure increases the value of the equilibrium constant. D The reaction is exothermic in the forward direction. Page 5 of 12

12. 10 cm3 of 0.01 mol dm3 barium hydroxide, Ba(OH)2, is diluted with 90 cm3 of water. What is the pH of the resulting solution? A 11.0 B 11.3 C 10.0 D 10.3 13. In acid solution BrO3  ions will slowly oxidize Br ions to Br2. BrO3  + 5Br + 6H+  3Br2 + 3H2O The variation for the initial rate of reaction with the concentrations of the reactants was investigated in four experiments. experiment number [BrO3 ] [Br ] [H+] relative rate 1 0.10 0.10 0.30 2 2 0.10 0.20 0.15 1 3 0.10 0.20 0.30 4 4 0.20 0.20 0.30 8 What are the orders of the reaction with respect to the three reactants? BrO3  Br H+ A 2 1 1 B 1 2 2 C 1 1 2 D 1 2 1 14. Consecutive elements X, Y and Z are in Period 3 of the Periodic Table. Element Y has the highest ionisation energy and the lowest melting point. What could be the identities of X, Y and Z? X Y Z A sodium magnesium aluminium B magnesium aluminium silicon C aluminium silicon phosphorus D silicon phosphorus sulphur Page 6 of 12

15. The highest oxides of the elements sodium to sulphur are separately added to water. Which diagram best represents the pH of the solutions produced? A B C D Na 2O MgO Al2O3 SiO2 P4O10 SO3 Na2O MgO Al2O3 SiO2 P4O10 SO3 pH pH Na2O MgO Al2O3 SiO2 P4O10 SO3 Na2O MgO Al2O3 SiO2 P4O10 SO3 pH pH 16. Which pair of reaction types is illustrated by the reaction sequence below? CH 3CH=CHCH3 CH3CH2CHICH3 CH3CH2CH(OH)CH3 A electrophilic addition and electrophilic substitution B electrophilic addition and nucleophilic substitution C nucleophilic addition and electrophilic substitution D nucleophilic addition and nucleophilic substitution HI in CH3CO2H NaOH(aq) Page 7 of 12

17. Mevalonic acid, 3,5-dihydroxy-3-methylpentanoic acid, is involved in cholesterol formation in the body. It is an oil that occurs as a mixture of the two interchanging molecules shown in the diagram. What names are used to describe the pair of interchanging reactions I and II? A condensation and addition B dehydrogenation and hydrogenation C esterification and hydrolysis D neutralisation and acidification 18. Four drops of 1-chlorobutane, 1-bromobutane and 1-iodobutane were put separately into three test-tubes containing 1.0 cm 3 of aqueous silv