2023 GDLSS Chem Prelims P1

Greendale Secondary School 1 Sec 4 Express Preliminary Examination 2023 Chemistry Name: ( ) Class/TG: GREENDALE SECONDARY SCHOOL Preliminary Examination 2023 CHEMISTRY 6092/01 Paper 1 Multiple Choice Secondary 4 Express 25 August 2023 1 hour Additional Materials: Multiple Choice Answer Sheet READ THESE INSTRUCTIONS FIRST Write in soft pencil. Do not use staples, paper clips, glue or correction fluid. Write your name, class and register number on the Answer Sheet and on the Question Paper in the spaces provided. 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 on this question paper. A copy of the Periodic Table is printed on Page 16. The use of an approved scientific calculator is expected, where appropriate. This document consists of 18 printed pages. [Turn over

Greendale Secondary School 2 Sec 4 Express Preliminary Examination 2023 Chemistry 1 In a volumetric experiment involving the addition of hydrochloric acid to 25.0 cm 3 of aqueous sodium hydroxide it is necessary to determine when the reaction is just complete. Which piece of apparatus could be used to determine the end-point of the reaction? A balance B gas syringe C stopwatch D thermometer 2 X, Y and Z are all mixtures of alcohols. A paper chromatogram is obtained for the samples of X, Y and Z. Which row is correct? statement 1 statement 2 A Z contains at least four alcohols. X, Y and Z could contain the same alcohol. B Z contains at least four alcohols. X, Y and Z could not contain the same alcohol. C Z contains no more than four alcohols. X, Y and Z could contain the same alcohol. D Z contains no more than four alcohols. X, Y and Z could not contain the same alcohol.

Greendale Secondary School 3 Sec 4 Express Preliminary Examination 2023 Chemistry 3 A crystalline product contains a mixture of two salts. A student tests the mixture to determine which ions are present. The results are shown. test number test observations 1 add dilute nitric acid, then effervescence as a gas is produced which gives a white precipitate with limewater add aqueous silver nitrate no precipitate is formed 2 add aqueous sodium hydroxide and warm, then dissolves and a gas is produced turning moist red litmus paper blue add aluminium foil effervescence as a gas is produced which turns moist red litmus paper blue Which is present in the mixture? A ammonium carbonate and sodium chloride B ammonium carbonate and sodium sulfate C ammonium nitrate and sodium carbonate D ammonium nitrate and sodium chloride 4 The nucleus of N3- contains a total of 31 particles. 15 of the particles have a charge. Which statement about the ion is correct? A It contains 15 neutrons and 12 electrons. B It contains 15 protons and 12 electrons. C It contains 15 protons and 15 electrons. D It contains 16 neutrons and 18 electrons.

Greendale Secondary School 4 Sec 4 Express Preliminary Examination 2023 Chemistry 5 The apparatus can be used to show the diffusion of gases. Which pair of gases X and Y would cause no movement of the water? X Y A C2H4 C2H6 B C2H4 N2 C CO2 C2H6 D CO NO2 6 The ion QH4 + can be represented by the “dot-and-cross” diagram shown. To which Group in the Periodic Table does Q belong? A I B III C IV D V

Greendale Secondary School 5 Sec 4 Express Preliminary Examination 2023 Chemistry 7 The diagram shows the electrolysis of aqueous sodium chloride and of molten sodium chloride. Which substance has both positive ions and mobile electrons? A aqueous sodium chloride B copper wire C graphite electrodes D molten sodium chloride 8 The diagram shows the arrangement of the ions in an ionic crystal. Which compound cannot have this arrangement of the ions? A calcium oxide, CaO B copper(II) sulfate, CuSO4 C magnesium chloride, MgCl2 D sodium chloride, NaCl

Greendale Secondary School 6 Sec 4 Express Preliminary Examination 2023 Chemistry 9 8 g of X2O3, an oxide of element X, contains 5.6 g of X. How many moles of X does 5.6 g of the element contain? A 2.4 16 × 2 3 B 2.4 16 × 3 2 C 8 16 × 2 3 D 8 16 × 3 2 10 What is the ratio of the volume of 2 g of hydrogen to the volume of 16 g of methane, both volumes at r.t.p.? A 1 to 1 B 1 to 2 C 1 to 8 D 2 to 1 11 Which volume of 0.1 mol/dm 3 hydrochloric acid is required to react completely with 25 cm3 of 0.2 mol/dm3 aqueous sodium carbonate? A 100 cm3 B 50 cm3 C 25 cm3 D 6.25 cm3 12 The equation for the burning of hydrogen is 2H2(g) + O2(g)  2H2O(g) One mole of hydrogen gas is mixed with one mole of oxygen gas and burnt. What will be present after the reaction? A 1 mol of steam only B 1 mol of steam + 0.5 mol of oxygen gas C 1 mol of steam + 0.5 mol of hydrogen gas D 2 mol of steam only

Greendale Secondary School 7 Sec 4 Express Preliminary Examination 2023 Chemistry 13 In the diagram, each cell contains an aqueous solution of a single salt and all four electrodes are platinum. Electrodes Q and S increase in mass during the electrolysis but no gas is given off at Q or S. If the increase in mass of Q is greater than the increase of mass of S in the same time, which statement must be true? 1 The cation of the solution in cell 1 is different from the cation of the solution in cell 2. 2 The current flowing in cell 1 is greater than the current flowing in cell 2. 3 The cation in cell 1 is the same as in cell 2 but the solution in cell 1 is more concentrated than in cell 2. 4 The loss of mass of electrode P is less than the loss of mass of electrode R. A 1 only B 1 and 2 C 2 and 3 D 4 only 14 In which of the following circuits is the bulb likely to shine most brightly? distilled water A dilute sulfuric acid B dilute sulfuric acid C distilled water D

Greendale Secondary School 8 Sec 4 Express Preliminary Examination 2023 Chemistry 15 The scheme shows four stages, I to IV, in the conversion of solid candlewax, C 30H62, into carbon dioxide and water. I C30H62(s)  C30H62(l) II C30H62(l)  C30H62(g) III C30H62(g) + 45.5O2(g)  30CO2(g) + 31H2O(g) IV 30CO2(g) + 31H2O(g)  30CO2(g) + 31H2O(l) Which stages are exothermic? A I and II B II and III C III and IV D I and IV 16 These statements are about the activation energy of a chemical reaction. 1 Chemical reactions in gases and liquids take place when molecules collide with sufficient energy to overcome the activation energy. 2 If the activation energy for a reaction is high, many of the collisions have enough energy to be successful and the reaction is fast. 3 A catalyst reduces the activation energy for a reaction and therefore the overall enthalpy change of the reaction is lower. Which statements are correct? A 1 only B 1 and 2 C 2 and 3 D 3 only

Greendale Secondary School 9 Sec 4 Express Preliminary Examination 2023 Chemistry 17 Excess magnesium ribbon is reacted with a fixed volume of hydrochloric acid and the volume of gas given off over time is measured. The results of two different experiments are shown. Which statement explains the differences between the results of the two experiments? A Reaction 1 uses a catalyst. B The acid used is twice as concentrated in reaction 1. C Th