RI 2022 Y5 Timed Practice QP

Name: ( ) Class: 23S0____ RAFFLES INSTITUTION 2022 Year 5 Term 3 Common Test HIGHER 2 CHEMISTRY 9729 30 June 2022 2 hours 15 minutes Additional Materials: Multiple Choice Answer Sheet Data Booklet READ THESE INSTRUCTIONS FIRST Write your name, 6 -digit index number and civics tutorial group in the spaces pro vided on the OMR sheet and the cover sheet on page 17. Shade in your 6-digit exam index number on the OMR Answer Sheet. This paper consists of three sections A, B and C. Section A (15 marks) consists of 15 multiple-choice questions. Answer this section first. Your OMR Answer Sheet will be collected after the first 30 minutes. Record your answers to this section in soft pencil on the separate OMR Answer Sheet. Section B (30 marks) consists of 3 structured questions. Answer all questions. Answers to this section are to be written in the spaces provided in the question paper. Section C (35 marks) consists of 2 free-response questions. Write your answers in the spaces provided in the question paper. If additional space is required, you should use pages 29–30 at the end of the booklet for Section C. The question number must be clearly shown. The number of marks is given in brackets [ ] at the end of each question or part question. Write in dark blue or black pen. You may be subject to penalty for writing answers in pencil. Answers to Sections B and C are to be handed in separately. Question Marks B1 / 6 B2 / 8 B3 / 16 This document consists of 30 printed pages. This document is copyrighted, please do not reproduce it without permission

2 Raffles Institution 2022 9729/J/22 [Turn Over Section A (15 marks) For each question, there are four possible answers, A, B, C, and D. Choose the one you consider to be correct. 1 Use of the Data Booklet is relevant to this question. Which gas contains the greatest number of atoms? A 2.80 g of nitrogen B 3.60 g of argon C 950 cm3 of C2H2 (measured at r.t.p.) D 5.10  1022 molecules of carbon dioxide 2 Chlorine reacts with hot aqueous sodium hydroxide to form chloride ions and another chlorine-containing product. When 0.03 mol of chlorine were reacted with excess sodium hydroxide, 0.05 mol of chloride ions were formed. What is the oxidation state of Cl in the other chlorine-containing product? A +1 B +3 C +5 D +7 3 Use of the Data Booklet is relevant to this question. Which statements regarding chromium are correct? 1 The electronic configuration of Cr+(g) at ground state is [Ar] 3d44s1. 2 Cr2+(g) and Cr3+(g) have the same number of paired electrons. 3 The energy required for the process, Cr 2+(g) ⎯→ Cr3+(g) + e –, is 2990 kJ mol–1. A 1, 2 and 3 B 1 and 2 C 2 and 3 D 2 only This document is copyrighted, please do not reproduce it without permission

3 Raffles Institution 2022 9729/J/22 [Turn Over 4 The 5th, 6th, 7th and 8th ionisation energies of four consecutive elements in the Periodic Table, W, X, Y and Z, are shown in the table below. W, X, Y and Z have atomic numbers less than 20. element 5th ionisation energy / kJ mol–1 6th ionisation energy / kJ mol–1 7th ionisation energy / kJ mol–1 8th ionisation energy / kJ mol–1 W 16 091 19 805 23 780 29 287 X 6274 21 267 25 431 29 872 Y 7004 8496 27 107 31 719 Z 6542 9362 11 018 33 604 Which element has the highest first ionisation energy? A W B X C Y D Z 5 J is an ionic compound comprising one polyatomic cation and a number of monoatomic anions. The cation has an overall charge of 2+, and contains platinum at an oxidation state of +4. The platinum is attached, via co-ordinate bonds (dative covalent bonds), to six other species which can be NH3 or Cl–. What is the formula of J? A Pt(NH3)4Cl2 B Pt(NH3)4Cl4 C Pt(NH3)6Cl2 D Pt(NH3)6Cl4 6 In the year 2000, argon fluorohydride, HArF, was synthesised as follows. Ar + HF ⎯→ HArF Which statement regarding the above molecules is correct? A HArF has a trigonal bipyramidal shape. B HF is non-polar as it is a linear molecule. C In HArF, Ar has ten electrons in its valence shell. D Hydrogen bonds exist between HArF molecules. This document is copyrighted, please do not reproduce it without permission

4 Raffles Institution 2022 9729/J/22 [Turn Over 7 The boiling points of three gases are given below. CH4 PH3 NH3 boiling point / C −161.5 –87.7 –77.7 Which statements are incorrect? 1 PH3 has a higher boiling point than CH4 because strong hydrogen bonds exist between PH3 molecules. 2 CH4 has a lower boiling point than NH3 because the CH4 molecule has fewer electrons than the NH3 molecule. 3 NH3 has a higher boiling point than PH 3 because NH 3 has stronger instantaneous dipole–induced dipole interactions than PH3. A 1, 2 and 3 B 1 and 2 C 1 and 3 D 2 and 3 8 The melting point of barium, 727 C, is much higher than the melting point of potassium, 63.5 C. Which statement is most relevant in explaining this difference? A The barium atom is larger than the potassium atom. B The barium atom is heavier than the potassium atom. C The barium ion, Ba2+, has a higher charge than the potassium ion, K+. D The barium ion, Ba2+, contains more electrons than the potassium ion, K+. 9 A piece of dry ice (solid CO2) weighing 4.40 g is placed in a 1.00 dm3 rigid bottle filled with air at 1 bar. The bottle is capped and the dry ice sublimes into gas. Given that the temperature is kept constant at 90.0 C, what is the final pressure, in bar, inside the bottle? [You may ignore the volume occupied by the solid dry ice.] A 1.31 B 1.75 C 3.98 D 4.02 This document is copyrighted, please do not reproduce it without permission

5 Raffles Institution 2022 9729/J/22 [Turn Over 10 Which of the following properties are observed for ideal gases? 1 At the same temperature and pressure, gases of the same volume contain the same number of particles. 2 For a fixed mass of gas at constant volume, the pressure of the gas is directly proportional to its absolute temperature. 3 For a fixed mass of gas at constant temperature, the volume of the gas is directly proportional to its pressure. A 1 only B 2 only C 1 and 2 D 2 and 3 11 The standard enthalpy changes for the following two processes are known. Br(g) + e− ⎯→ Br−(g) 1 2 Br2(l) + e− ⎯→ Br−(aq) What additional data is needed to determine the standard enthalpy change of hydration of Br−(g)? A first ionisation energy of Br B enthalpy change of solution of Br2(l) C enthalpy change of formation of Br2(l) D enthalpy change of atomisation of Br2(l) 12 When equal volumes of 0.25 mol dm−3 sulfuric acid and 0.25 mol dm−3 of ethanoic acid were separately neutralised by dilute sodium hydroxide , the heat energy released w as p kJ and q kJ respectively. Which relationship between p and q is correct? A p > 2q B p = q C p = 2q D p = 1 2 q This document is copyrighted, please do not reproduce it without permission

6 Raffles Institution 2022 9729/J/22 [Turn Over 13 Elemental sulfur occurs in two allotropic forms , α-sulfur and β -sulfur. They undergo combustion to form SO2(g). The standard enthalpy changes of combustion are shown below. ∆Hc (α-sulfur) = –