2022 DMSS Chem Prelims P1

1 [Turn over DAMAI SECONDARY SCHOOL Preliminary Examination 2022 CANDIDATE NAME CLASS INDEX NUMBER CHEMISTRY Paper 1 Multiple Choice Secondary 4 Express Setter: Ms See Pei Zhen Additional Materials: Multiple Choice Answer Sheet 6092/01 23 August 2022 1 hour 40 marks READ THESE INSTRUCTIONS FIRST Write in soft pencil. Do not use staples, paper clips, highlighters, glue or correction fluid. Write your name, index number and class on all the work you hand in. There are forty questions in this section. 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. 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 15. The use of an approved scientific calculator is expected, where appropriate. This document consists of 15 printed pages.

2 1 The graph shows the change in temperature with time when steam is cooled from 120 °C. Which of the following shows the correct change taking place between different points of the graph? points change A P to Q kinetic energy of particle remains constant B Q to R water boiling C R to S the volume of liquid is decreasing D T to U water freezing 2 A mixture is formed when two or more substances are physically combined together. Which statement about mixtures is true? A Equal masses of two substances must be used. B The mixture shows similar chemical properties to those of its constituents. C The substances must be both metals. D When the substances are combined, an ionic or a covalent compound forms. 3 What is necessary for two substances to be separated by paper chromatography? A They are both soluble in water. B They have the same solubility in the same solvent. C They have different solubilities in the same solvent. D Their solids have different densities in the same solvent. temperature/°C time/s 120 P Q R S T U

3 [Turn over 4 Whisky is a beverage composed of mainly water and ethanol. Scotch Whisky is usually made up of 60 % of ethanol by volume. A sample of Scotch Whisky is distilled using fractional distillation. Ethanol boils at 78 °C. Which graph shows the change in concentration of ethanol in the sample as the distillation proceeds? A B C D 5 Q is an element in the Periodic Table. Which of the following represents an isotope of Q3581? A Q3379 B Q3579 C Q4281 D Q4681 6 Which ion has the lowest number of electron shells containing electrons? A Al3+ B Be2+ C N3– D S2– concentration of ethanol in sample/% time/s 60 0 concentration of ethanol in sample/% time/s 60 0 concentration of ethanol in sample/% time/s 40 0 concentration of ethanol in sample/% time/s 40 0

4 7 The diagram shows a molecule of pyridine-2-carboxylic acid. Determine the number of valence electrons involved in bonding and the number of valence electrons not involved in bonding in one molecule of pyridine-2-carboxylic acid. number of valence electrons involving in bonding number of valence electrons not involved in bonding A 18 10 B 18 46 C 36 10 D 36 20 8 X, Y and Z are compounds of elements in Period 3. Their electrical conductivities are shown in the table below. X Y Z electrical conductivity of the compound when molten good good does not conduct electrical conductivity of the mixture obtained upon adding the compound to water does not conduct good does not conduct What are the possible identities of X, Y and Z? X Y Z A Al2O3 NaCl diamond B Al2O3 Cu diamond C Na2SO4 Al2O3 NaCl D Na2SO4 Cu Br2 C N C C C C H C H H H O H O

5 [Turn over 9 Both hydrochloric acid and ethanoic acid have the same concentration of 1.00 mol/dm3. Which method(s) is/are suitable to test their strengths? 1 using universal indicator solution 2 measuring their electrical conductivity 3 titration using 1.00 mol/dm3 of aqueous sodium hydroxide A 2 only B 3 only C 1 and 2 D 1, 2 and 3 10 Which pair of solutions, when mixed together, forms a precipitate? A sodium chloride and barium nitrate B sodium nitrate and ammonium sulfate C silver sulfate and nitric acid D silver nitrate and hydrochloric acid 11 An aqueous solution containing a mixture of calcium ions, copper(II) ions and zinc ions was treated with an excess of aqueous ammonia. The reaction mixture was filtered. What is the colour of the residue? A white B blue C green D no residue is obtained 12 256 g of sulfur vapor has the same volume as 160 g of bromine gas at the same temperature and pressure. What is the formula of a molecule of sulfur? A S16 B S8 C S4 D S2 13 Which volume of 0.1 mol/dm3 sulfuric acid is required to react completely with 50 cm3 of 0.2 mol/dm3 lithium hydroxide solution? A 0.5 cm3 B 1 cm3 C 50 cm3 D 100 cm3

6 14 Which statement about the ions of Group II elements is correct? A They have two valence electrons. B They contain an odd number of electrons. C They contain more electrons than protons. D They contain more protons than electrons. 15 Which pair of elements, when reacted together, gives the least violent reaction? A lithium and iodine B rubidium and fluorine C lithium and fluorine D rubidium and iodine 16 An element R is in Group VII of the Periodic Table. Which of the following formulae is incorrect? A R– B HR C R2 D MgR 17 Which of the following shows the correct source and effect of the named pollutant? pollutant source effect A methane combustion of fossil fuel global warming B oxides of nitrogen lightning activity acid rain C ozone depletion of ozone layer acid rain D sulfur dioxide volcanoes global warming 18 Which of the following gives the definitions of reduction? oxygen hydrogen electrons A loss gain gain B loss loss gain C gain gain loss D gain loss loss

7 [Turn over 19 Sodium hypochlorite reacts with zinc metal to form zinc oxide and sodium chloride. NaOCl + Zn → ZnO + NaCl Which statement about this reaction is correct? A oxygen changes from oxidation state 0 to –2 B chlorine changes from oxidation state +1 to –1 C sodium changes from oxidation state +3 to +1 D zinc remains in oxidation state 0 20 Iodine solution turns from brown to colourless when added to substance X. Based on this observation, what can be deduced about substance X? A Substance X is an oxidising agent. B Substance X is a reducing agent. C Substance X is a bleaching agent. D Substance X can only be aqueous sodium chloride. 21 The carbonates of zinc, potassium and silver were heated strongly. Which graph best shows the relative volume of gas collected in the first minute of the reaction? A B C D volume of gas/cm3 ZnCO3 K2CO3 Ag2CO3 volume of gas/cm3 ZnCO3 K2CO3 Ag2CO3 volume of gas/cm3 ZnCO3 K2CO3 Ag2CO3 volume of gas/cm3 ZnCO3 K2CO3 Ag2CO3

8 22 Which statement about alloys is always correct? A Alloys contains only metallic atoms. B Their structure contains a ‘sea of electrons’. C They have higher melting point than its pure metals. D They have equal or better electrical conductivity than its pure metal. 23 Metals are found naturally in its elemental state or as metallic compounds. Metals can be extracted from their compounds through either electrolysis or using carbon as a reducing agent. Which row is correct? exists as an element obtained through electrolysis obtained by reduction using carbon A Au Na Pb B Mg Na Pb C Au Ag Mg D Mg Ag Ca 24 Which of th