JJC H1 CHEM P1 Qn

JURONG JUNIOR COLLEGE JC 2 PRELIMINARY EXAMINATION Higher 1 CHEMISTRY 8872/01 Paper 1 Multiple Choice 17 September 2015 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 index 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 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. The use of an approved scientific calculator is expected, where appropriate. A Data Booklet is provided. Do not write anything on the Data Booklet. This document consists of 13 printed pages and 1 blank page. [Turn over

2 Jurong Junior College 8872/01/J2Preliminary Examination/2015 [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 9 4Be is used in the production of ‘fast neutrons’. How many neutrons are present in 0.09 g of 9 4Be ? [L = Avogadro constant] A 0.01 L B 0.04 L C 0.05 L D 0.09 L 2 Use of the Data Booklet is relevant to this question. Ferrochrome, an alloy of iron and chromium, can be dissolved in dilute sulfuric acid to produce a mixture of FeSO 4 and Cr 2(SO4)3. The FeSO 4 reacts with Na 2Cr2O7 in acid solution according to the following equation. 14H+ + 6Fe2+ + Cr2O7 2−  2Cr3+ + 6Fe3+ + 7H2O When 1.00 g of ferrochrome is dissolved in dilute sulfuric acid, and the resulting solution titrated, 13.10 cm 3 of 0.100 mol dm−3 Na2Cr2O7 is required for complete reaction. What is the percentage by mass of Fe in the sample of ferrochrome? A 1.22 B 4.39 C 12.2 D 43.9 3 Use of the Data Booklet is relevant to this question. In an experiment, a sample of Americium element (Am) was vaporised, ionised and passed through an electric field. Analysis revealed that a beam of 241Am+ gives an angle of deflection of 2°. What would be the angle of deflection for a sample of singly charged calcium ions? A 12.0° B 6.0° C 2.0° D 0.3° 4 Use of the Data Booklet is relevant to this question. In some types of spectroscopy, it is important to know if ions are isoelectronic. Which ion is not isoelectronic with K+? A Ca2+ B Cl− C S2− D Ti3+

3 Jurong Junior College 8872/01/J2Preliminary Examination/2015 [Turn Over 5 Use of the Data Booklet is relevant to this question. Some isotopes are unstable and decompose nat urally. In one type of decomposition, a neutron in the nucleus decomposes to form a proton, which is retained in the nucleus, and an electron, which is expelled from the atom. Which change describes a process of this sort? A 11C 12C B 22Na 22Ne C 32P 31P D 40K 40Ca 6 The Valence Shell Electron Pair Repulsion theo ry (VSEPR) is used to predict the shapes of molecules. Which shape is correctly predicted by VSEPR? number of bonded electron pairs around central atom number of lone pairs around central atom shape A 2 2 non-linear B 2 2 tetrahedral C 3 1 trigonal planar D 3 1 linear 7 2-methylpropan-1-ol and butan-1-ol are struct ural isomers. 2-methylpropan-1-ol has a lower boiling point. Which statement explains why the boiling point of 2-methylpropan-1-ol is lower than that of butan-1-ol? A 2-methylpropan-1-ol cannot form hydrogen bonds. B 2-methylpropan-1-ol has weaker covalent bonds than butan-1-ol. C 2-methylpropan-1-ol has weaker van der Waals’ forces than butan-1-ol. D 2-methylpropan-1-ol molecules have more surface area than butan-1-ol molecules.

4 Jurong Junior College 8872/01/J2Preliminary Examination/2015 [Turn Over 8 Which diagram best represents the structure of solid magnesium oxide? A C B D 9 A stable molecule containing atoms of the elements, X, Y and Z has the following structure. Which elements could be X, Y and Z? X Y Z A N P C l B O S C l C B C H D P Si H 10 What is the effect of a catalyst on the rate constants, k1 for the forward reaction and k-1 for the reverse reaction and on the equilibrium constant K, for a reversible reaction? k1 k-1 K A Increase Decrease No effect B Increase Increase No effect C Increase Increase Increase D No effect No effect Increase

5 Jurong Junior College 8872/01/J2Preliminary Examination/2015 [Turn Over 11 Lead is the final product formed by a series of changes in which the rate-determining step is the radioactive decay of uranium-238. This radioactive decay is a first-order reaction with a half-life of 4.5 x 109 years. How long would it take for a rock sample, originally lead-free, to contain a molar proportion of uranium to lead of 1:3? A 1.5 x 109 years B 2.25 x 109 years C 9.0 x 109 years D 13.5 x 109 years 12 The enthalpy change of formation of Mn(NO3)2(s) is −696 kJ mol−1. The enthalpy change of formation of MnO2(s) is −520 kJ mol−1. The enthalpy change of formation of NO2(g) is +33 kJ mol−1. On heating, Mn(NO3)2 decomposes into MnO2 and NO2. Mn(NO3)2(s)  MnO2(s) + 2NO2(g) What is the value of the standard enthalpy change of this reaction? A −242 kJ mol−1 B −209 kJ mol−1 C +209 kJ mol−1 D +242 kJ mol−1 13 For which equation is the enthalpy change c orrectly described as an enthalpy change of formation? A C(g) + O2(g)  CO2(g) B C(s) + ½ O2(g)  CO(g) C 2N(g) + 4O(g)  N2O4(g) D 2NO(g) + O2(g)  2NO2(g)

Jurong Ju 14 U I ( r W 15 A N W 16 Th th W unior College Use of the D n an exp e (0.0326 mo rose from 25 What is the A −1410 B −769 k C −30.7 D −16.7 A 1 dm 3 s o NaOH(aq). What was th A 2.19 B 2.40 he trends in e graphs. Which physic A atom B elect C first D melt Data Bookle eriment to l) of the fu e 5 °C to 55 ° experiment 0 kJ mol−1 kJ mol−1 kJ mol−1 kJ mol−1 olution wa s he pH of the n three phys cal property mic radius trical condu ionisation e ing point 8872/01/J et is relevan calculate t el was use d °C. tal value for s made by e resulting s sical proper y is not illust uctivity energy 6 J2Preliminary nt to this que the enthal p d to heat 2 r the enthal mixing 0. 0 solution? C 2.60 D 2.82 rties of the e trated? y Examination estion. py change 00 g of wa t py change 0040 mol o elements Na n/2015 of combu s ter. The te m of combust of HC l(aq) a, Mg, Al, S stion of a mperature o ion, ∆Hc, of and 0.002 5 Si, P and S [Turn Ove fuel, 1.5 g of the wate f the fuel? 5 mol of are shown er g r in

7 Jurong Junior College 8872/01/J2Preliminary Examination/2015 [Turn Over 17 X, Y and Z are compounds of three elements in Period 3. Their electrical conductivities are shown in the table. X Y Z conductivity of the compound in the molten state good does not conduct does not conduct conductivity of the mixture obtained by adding the compound to water good good does not conduct What could be compounds X, Y and Z? X Y Z A Al2O3 SiC l4 NaF B NaF Al2O3 SiC l4 C NaF SiCl4 SiO2 D SiCl4 A l2O3 SiO2 18 The diagram shows the structure of artemisinic acid, an intermediate for making th