2022 PgSS Chem Prelims P1

EXP PUNGGOL SECONDARY SCHOOL SECONDARY 4 EXPRESS PRELIMINARY EXAMINATION QUESTION & ANSWER BOOKLET NAME CLASS INDEX NUMBER Chemistry Paper 1 6092 30 August 2022 Additional materials: MCQ answer Sheet 1 hour READ THESE INSTRUCTIONS FIRST Write your class, register number and name on all the work you hand in. Write in soft pencil. Do not use staples, paper clips, highlighters, glue or correction fluid. There are forty 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. A copy of the Periodic Table is printed on page 18. The use of an approved scientific calculator is expected, where appropriate. For Examiner’s use Parent’s Signature Section A /40 - - - - Total /40 This paper consists of 18 printed pages and 0 blank page. ���

2 1 A student is preparing a gas in the laboratory that is soluble in water and less dense than air. What is the most suitable method for collecting the gas? A B C D 2 The diagram shows a beaker full of gas X inverted over a porous pot containing gas Y. A known liquid is used in the container. None of the gases provided below is soluble in the liquid. Which pair of gases will lead to the liquid spilling out at the outlet O? Gas X Gas Y A chlorine hydrogen B argon neon C flourine helium D neon flourine ���

3 3 The diagram below shows the cooling curve for an unknown substance. The substance changes from liquid to solid. 1 The particles in the substance below temperature T1 vibrate about their fixed position. 2 The substance could be a sample of crude oil. 3 The freezing point is the average of T1 and T2. Which statement(s) is/are correct? A 1, 2 and 3 B 1 and 2 only C 1 only D 2 only 4 A salt, R, on warming with excess aqueous sodium hydroxide, evolved a gas that turned damp red litmus paper blue. When no more gas was evolved, a piece of aluminium foil was added, and a further evolution of the same gas occurred. What could be R? A ammonium nitrate B ammonium sulfate C zinc nitrate D zinc sulfate ���

4 5 An ion Y2+ contains 19 neutrons and 18 electrons. Which of the following shows the proton number and nucleon number of Y? proton number nucleon number A 16 35 B 18 37 C 19 38 D 20 39 6 The electronic configuration of X is 2,8,4. X reacts with an element Y from Group VII to form a compound. Which of the following best describes the compound formed? type of bonding formula of compound A ionic XY4 B ionic X4Y C covalent XY4 D covalent X4Y 7 The boiling points of beryllium oxide and sodium oxide are shown below. boiling point / oC beryllium oxide 3900 sodium oxide 1950 Beryllium oxide does not conduct electricity in both solid and molten states. Which of the following best explain the difference in boiling points between the two compounds? A Electrostatic forces of attraction between the oppositively charged ions in beryllium oxide is stronger. B Metallic bonds in beryllium oxide are stronger. C Covalent bonds in beryllium oxide are stronger. D Intermolecular forces of attraction in beryllium oxide is stronger. ���

5 8 Which structure does not contain atoms bonded to other atoms by four covalent bonds? A graphite B silicon dioxide C poly(propene) D carbon tetrachloride 9 Some of the medicinal tablets contain calcium. When the calcium in these tablets reacts with oxygen, it forms calcium oxide. A sample of 100.0 g of calcium tablets yields 28.0 g of calcium oxide. What is the percentage by mass of calcium in the tablet? A 10.0% B 15.0% C 20.0% D 25.0% 10 4.00 g of a metal oxide, YO2, is heated with carbon. 3.15 g of metal Y is obtained. YO2 + C → Y + CO2 What is the identity of Y? A Co!"#$ B Zr%&$' C In%$''# D Sn#&''$ 11 Which statement about the electrolysis of molten sodium chloride is correct? A A gas that bleaches damp litmus paper is produced at the anode. B A gas that relights a glowing splint is produced at the anode. C Sodium metal is deposited at the anode. D A gas that extinguishes a lighted splint is produced at the cathode. ���

6 12 Inert electrodes are used in the electrolysis of an aqueous solution containing both copper(II) sulfate and zinc sulfate. What will be produced at the cathode? A copper B zinc C hydrogen D oxygen 13 Two cells were set up as shown in the diagram. The arrows show the direction of electron flow in the external circuits. Which set of metals would give the electron flow in the directions shown? metal X metal Y metal Z A iron zinc copper B copper iron zinc C zinc iron copper D zinc copper iron 14 The enthalpy change of combustion of four different fuels are shown below. Reaction Enthalpy change/kJ 2C2H6 + 7O2 → 4CO2 + 6H2O −3120 C2H5OH + 3O2 → 2CO2 +3H2O −1367 2C4H8 + 12O2 → 8CO2 + 8H2O −5432 2C4H10 + 13O2 → 8CO2 + 10H2O −5756 Which fuel releases the most energy per gram of fuel? A C2H6 B C2H5OH C C4H8 D C4H10 dilute sulfuric acid ���

7 15 The diagram below shows the energy profile diagram of a reversible reaction. P + Q ⇌ R + S What is the ethalpy change of reaction, ∆H and activation energy, Ea for the reverse reaction? ∆H in kJ / mol Ea in kJ / mol A − 50 120 B + 50 120 C − 50 170 D + 50 170 16 In the reaction between magnesium and sulfuric acid, the following changes could be made to the conditions. 1 increase concentration of the acid 2 increase in particle size of magnesium 3 increase in pressure on the system 4 increase in temperature of the system Which changes will increase the rate of reaction? A 1, 2 and 4 B 1 and 4 only C 1, 3 and 4 only D 2 and 4 only ���

8 17 In the graph, curve I was obtained when 1 g of granulated zinc was reacted with an excess of 0.1 mol/dm3 nitric acid at 50oC. Which of the following changes would give curve II? A increasing the temperature B using 1 g of powdered zinc C adding 25 cm3 of 0.025 mol/dm3 of nitric acid to the original acid D reducing the pressure of the reacting mixture 18 In which of the following reactions is the underlined substance oxidised? A Cl2 + 2I- → I2 + 2Cl- B 3CuO + 2NH3 → N2 + 3H2O + 3Cu C MgCO3 + 2H+ → Mg2+ + CO2 + H2O D Pb2+ + SO42- → PbSO4 19 The table below shows the results of adding weighed pieces of nickel metal in salt solutions of metals P, Q, R and S. solution initial mass of nickel/ g mass of nickel after 10 minutes/ g P 5.0 4.0 Q 5.0 4.5 R 5.0 3.5 S 5.0 0.0 Which of the following statements is correct? A Metal S can displace the metal in solution R. B Metal S is below nickel in the reactivity series. C Metal R is above nickel in the reactivity series D Metal P is above metal Q in the reactivity series. ���

9 20 The diagram shows three types of item. cutlery cooking pan instruments used in hospitals Which method of rust prevention can be used for all three types of item? A coating with paint B galvanising C using alloy such as stainless steel D coating with grease 21 Compound X is heated with carbon using the apparatus shown. No precipitate is formed in limewater after heating for some time. What could be X? A calcium oxide B zinc oxide C lead(II) oxide D copper(II) oxide ���

10 22 The table below refers to four metals and some of their compounds. Metal Action of heat on metal carbonate Effect of hydrogen on heated oxide Action of dilute hydrochloric acid on met