2023 FHSS Chem Prelims P1

Candidate Name: Class Index No. FUHUA SECONDARY SCHOOL 4E Secondary Four Express Preliminary Examination 2023 Fuhua Secondary Fuhua Secondary Fuhua Secondary Fuhua Secondary Fuhua Secondary Fuhua Secondary Fuhua Secondary Fuhua Secondary Fuhua Secondary Fuhua Secondary Fuhua Secondary Fuhua Secondary Fuhua Secondary Fuhua Secondary Fuhua Secondary Fuhua Secondary Fuhua Seconda ry Fuhua Secondary Fuhua Secondary Fuhua Secondary Fuhua Secondary Fuhua Secondary Fuhua Secondary Fuhua Secondary Fuhua Secondary Fuhua Secondary Fuhua Secondary Fuhua Secondary Fuhua Secondary Fuhua Secondary Fuhua Secondary Fuhua Secondary Fuhua Secondary Fuhua Secondary Fuhua Seconda ry Fuhua Secondary CHEMISTRY 6092/01 Paper 1 Multiple Choice 30 August 2023 0800 – 0900 1 hour Additional Material: Optical Mark Recognition (OMR) READ THESE INSTRUCTIONS FIRST Write in soft pencil. Do not use staples, paper clips, glue or correction fluid. Write your name, class, index number on the OMR and this question booklet. 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 OMR. Each correct answer will score one mark. A mark will not be deducted for a wrong answer. Any rough working should be done on this paper. A copy of the Periodic Table is printed on page 14. The use of an approved scientific calculator is expected, where appropriate. Setter: Mr Elton Tan Vetter: Miss Nur Hanis This question paper consists of 14 printed pages including this page. PARENT'S SIGNATURE FOR EXAMINER'S USE 40

2 1 A student put exactly 25.0 cm3 of dilute hydrochloric acid into a conical flask. He added 2.5 g of solid sodium carbonate and measured the change in temperature of the mixture. Which apparatus does the student need? A balance, measuring cylinder, thermometer B balance, pipette, stopwatch C balance, pipette, thermometer D burette, pipette, thermometer 2 Paper chromatography is carried out on three different mixtures of dyes, using the same solvent. Each mixture contains at least one of the dyes W, X, Y and Z. The Rf values of the dyes in the three mixtures are shown. dye Rf values from mixture 1 Rf values from mixture 2 Rf values from mixture 3 W 0.14 0.14 0.14 X 0.00 0.00 0.00 Y 0.50 0.50 0.50 Z 0.82 0.82 0.00 Which conclusion is correct? A Dye X is the most soluble dye. B Dye Y is the only dye present in all three mixtures. C Dye W is nearest to the solvent front and present in all three mixtures. D Dye Z is nearest to the solvent front and is found in only two of the mixtures. 3 The diagram below shows a set-up to prepare a dry sample of ammonia gas. The experiment failed. What modifications should be done to correct the set-up? 1 An alkali should be placed in the test-tube instead of an acid. 2 Anhydrous calcium oxide should be used instead of concentrated sulfuric acid. 3 The gas should be collected in a gas syringe instead of by displacement of water. A 2 only B 1 and 2 C 2 and 3 D 1, 2 and 3 concentrated sulfuric acid

3 4 The diagram shows a beaker full of gas X inverted over a porous pot containing gas Y. None of the gases provided below is soluble in the liquid inside the container. Which pair of gases will lead to the liquid spilling out at outlet O? X Y A neon nitrogen monoxide B fluorine carbon monoxide C chlorine hydrogen D propane neon 5 The scheme below shows reactions of a gas X. Which statement is correct? A Gas X is bromine. B In stage 2, iron(II) sulfate acts as an oxidising agent. C The brown precipitate formed in stage 3 is iron(II) hydroxide. D In stage 1, iodide ion is oxidised as it loses electrons to form iodine.

4 6 The diagram shows the relative mass and the relative charge of two particles, ● and ○ , present in atoms and ions. Which of these particles are present in a hydrogen atom and a hydrogen ion? hydrogen atom, H hydrogen ion, H+ ● ○ ● ○ A yes yes yes yes B yes yes no no C yes no yes no D yes no no no 7 Epsom salts contain magnesium sulfate and are often used as a natural remedy for muscle aches, inflammation, and stress. A student wrote down some statements about magnesium sulfate. 1 It is made up of a giant lattice structure. 2 The ratio of positive to negative ions is 1:2. 3 There are both ionic and covalent bonding present. 4 Strong electrostatic forces of attraction exist between Mg2+, S2− and O2− ions. Which of the above statements are correct? A 1 and 2 B 1 and 3 C 1 and 4 D 1, 3 and 4 8 An amino acid, alanine, has the following structure. How many pairs of valence electrons are involved in bonding in the alanine molecule? A 5 B 9 C 13 D 26

5 9 The formula of a nitride of element X is X3N2. 23.8 g of X3N2 contains 4.5 g of X. How many moles are there in 4.5 g of X? A 19.3 14 × 2 3 B 19.3 14 × 3 2 C 9.65 14 × 2 3 D 9.65 14 × 3 2 10 50 cm3 of ethane is burnt completely in 200 cm3 of oxygen at 200°C. What is the total volume of the gases, measured at room temperature and pressure, at the end of the reaction? A 100 cm3 B 125 cm3 C 250 cm3 D 275 cm3 11 Citric acid, the predominant acid in lemon juice, is a tribasic acid. A student titrated 25.0 cm3 samples of lemon juice with 0.55 mol/dm 3 NaOH. The average titration volume was 29.50 cm3. The molar mass of citric acid is 192 g/mol. What was the concentration of citric acid in the lemon juice? A 0.216 g/dm3 B 41.5 g/dm3 C 125 g/dm3 D 374 g/dm3 12 The diagram below shows the energy profile for a reaction. Which statements about this reaction are correct? 1 Route 1 uses a catalyst. 2 The reaction is exothermic. 3 Route 1 and route 2 give the same overall equation for the reaction. 4 More energy is taken in to break the bonds than released when the bonds are formed. A 1 and 3 B 2 and 3 C 2 and 4 D 2, 3 and 4

6 13 Four metals, W, X, Y and Z were connected in pairs as shown and the voltage was recorded. The results obtained are recorded in the table below. cell metals used voltage / V positive terminal 1 W and X 1.10 W 2 X and Y 1.46 Y 3 X and Z 0.47 X Which statement is correct? A Y is the most reactive metal. B The voltage obtained when W and Y are used is 0.36 V. C The voltage obtained when Z and Y are used is 0.99 V. D W can displace metal Z from a solution containing cations of Z. 14 The enthalpy change of combustion for four different fuels are shown below. reaction enthalpy change (kJ / mol) CH4 + 2O2 → CO2 + 2H2O −890 C2H5OH + 3O2 → 2CO2 +3H2O −1367 C4H8 + 6O2 → 4CO2 + 4H2O −2717 2C4H10 + 13O2 → 8CO2 + 10H2O −5756 Which fuel releases the most energy per gram of fuel? A CH4 B C2H5OH C C4H8 D C4H10 15 The diagram shows the outer shell electron arrangement of a molecule of a compound made up of elements Y and Z. What is the formula of the compound formed between Z and magnesium? A MgZ B MgZ2 C Mg2Z3 D Mg3Z2 positive electrode negative electrode dilute sulfuric acid

7 16 Which method produces the highest yield of calcium sulfate from calcium carbonate? A addition of dilute sulfuric acid B addition of aqueous ammonium sulfate C addition of dilute hydrochloric acid, followed by barium sulfate D addition of dilute hydrochloric acid, followed by aqueous ammonium sulfate 17 The nitrogen cycle is a biochemical cycle that occurs naturally. It involves the conversion of nitrogen-containing substances that takes place through biological and physical processes. Which of the following conversion of nitrogen-containing substances shows the greatest increase in oxidation number? A NH4+ to NO3– B N2 to NO3– C NO2– to N2O D N2O to NO3– 1