2022 LVSS Chem Prelims P1

LOYANG VIEW SECONDARY SCHOOL Preliminary Examination 2022 Secondary Four Express CANDIDATE NAME : ……………………………………………………………….......... CLASS : …………………. INDEX NUMBER : ……………. CHEMISTRY 6092/01 Paper 1 Multiple Choice 12 September 2022 1 hour Additional Materials: Multiple Choice Answer Sheet READ THESE INSTRUCTIONS FIRST Write in soft pencil. Do not use staples, paper clips, highlighters, glue or correction fluid. Write your name, class and index number on the Answer Sheet in the spaces provided unless this has been done for you. 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 17. The use of an approved scientific calculator is expected, where appropriate. Setter: Ms Imma Wong This paper consists of 17 printed pages. ���

2 1 Which group of substances consists of mixtures only? A air, petroleum and steel B nylon, glucose and ethanol C limestone, seawater and ozone D haematite, brass and sodium chloride 2 The graph (not drawn to scale) shows how the temperature of oxygen and nitrogen changes when they are heated. At which temperature will there be two different states of matter in a mixture of oxygen and nitrogen under similar conditions? A −180 oC B −200 oC C −215 oC D −220 oC 3 A balloon filled with gas X is placed inside a beaker that is filled with gas Y as shown. The balloon shrinks in size after a few hours. Which could be the identities of gases X and Y? X Y nitrogen ammonia ammonia argon argon oxygen oxygen nitrogen A B C D −183 −196 −210 −218 N2 O2 temperature / oC time / min after a few hours X Y balloon ���

3 4 An element J has a nucleon number of 45. The ion, J3+, contains 18 electrons. How many neutrons are there in an atom of J? A 18 B 21 C 24 D 45 5 Which statement describes the arrangement and movement of particles of sodium hydroxide in water? A Ions are closely packed and does not move. B Ions are widely spaced and move randomly. C Molecules are widely spaced and move randomly. D Molecules are closely packed and move randomly. 6 A stable molecule containing atoms of elements X, Y and Z has the structure shown. What could elements X, Y and Z be? X Y Z carbon sulfur hydrogen nitrogen silicon sulfur nitrogen silicon hydrogen silicon sulfur chlorine A B C D Y Y Y X X X Z Z Z ���

4 7 The structures of atoms of elements L and M are shown. L M What is the mass of 1 mole of the compound formed by L and M? A 11 g B 12 g C 23 g D 30 g 8 Graphane, an allotrope of carbon has a similar structure to graphite, except that it has one hydrogen atom attached to each carbon as shown in the diagram. Which of the properties listed below are properties of graphane? 1 It has a giant molecular structure. 2 It has a high melting point. 3 It is ‘slippery’ in nature. 4 It conducts electricity in the solid state. A 1, 2 and 3 B 1, 2 and 4 C 1, 3 and 4 D 2, 3 and 4 3p 4n 8p 8n e e e hydrogen atom carbon atom e e e e e e e e ���

5 9 Naphthalene is the main ingredient of mothballs. It contains 93.75 % of carbon and 6.25 % of hydrogen. If the relative molecular mass of naphthalene is 128, what is its molecular formula? [relative atomic masses, Ar : H, 1; C, 12] A CH B C5H4 C C10H8 D C10H10 10 A pure hydrocarbon is used to heat homes. When 10 cm3 of the hydrocarbon is burned in 70 cm3 of oxygen, the final gaseous mixture contains 30 cm3 of carbon dioxide and 20 cm3 of unreacted oxygen. All gaseous volumes are measured under identical conditions. What is the chemical formula of the hydrocarbon? [relative atomic masses, Ar : H, 1; C, 12; O, 16] A C2H6 B C3H6 C C3H8 D C4H10 11 The equation for the reduction of iron ore in the blast furnace is shown. Fe2O3 + 3CO → 2Fe + 3CO2 When 90 tonnes of the iron ore were reduced, 56 tonnes of molten iron were produced. What is the percentage purity of the iron ore used? [relative atomic masses, Ar : C, 12; O, 16; Fe, 56] A 11.1 % B 42.2 % C 56.3 % D 88.9 % 12 What is the ionic equation for the reaction between sodium carbonate and sulfuric acid? A H+ + OH− → H2O B 2Na+ + SO42− → Na2SO4 C CO32− + 2H+ → CO2 + H2O D 2CO32− + 2H+ → 2CO2 + H2O ���

6 13 The colour changes of a recently discovered indicator is shown in the table. pH colour 0 – 3.5 3.5 – 5 5 - 14 red green purple Which pair of substances could be distinguished by the new indicator? A hydrochloric acid and ethanoic acid B aqueous sodium chloride and water C aqueous ammonia and aqueous sodium hydroxide D aqueous potassium nitrate and aqueous potassium hydroxide 14 Which statement about oxides is true? A Nitrogen dioxide is a neutral oxide. B Zinc oxide dissolves readily in water to form an alkaline solution. C Copper(II) oxide reacts with dilute sulfuric acid to give a blue solution. D Carbon monoxide reacts with aqueous sodium hydroxide to form a salt and water. 15 A student recorded the following observations when he mixed two substances: “no effervescence, solution changes colour, no precipitate forms” Which two substances could have been used? A dilute nitric acid and lead(II) carbonate B dilute hydrochloric acid and iron(II) oxide C aqueous sodium hydroxide and dilute sulfuric acid D aqueous potassium chloride and aqueous silver nitrate ���

7 16 A sample of an alloy containing two metals was subjected to the following tests. What are the two metals present in the alloy? A iron and zinc B iron and lead C iron and copper D copper and zinc 17 Which salts are best prepared by adding excess acid to an insoluble base? A magnesium chloride, zinc sulfate, lead(II) nitrate B sodium chloride, copper(II) nitrate, calcium sulfate C copper(II) carbonate, barium sulfate, silver chloride D sodium chloride, ammonium nitrate, potassium sulfate 18 Hydrogen peroxide was added to separate test tubes containing aqueous potassium iodide and aqueous acidified potassium manganate(VII). The iodide ions were oxidised and the manganate(VII) ions are reduced. What are the colour changes seen? potassium iodide acidified potassium manganate(VII) brown to colourless purple to colourless brown to colourless colourless to purple colourless to brown purple to colourless colourless to brown colourless to purple A B C D alloy solution P precipitate formed amount of precipitate decreases dilute sulfuric acid a few drops of aqueous ammonia excess aqueous ammonia ���

8 19 A mineral, Jarosite, has the molecular formula KFe3(OH)6(SO4)2. What is the oxidation state of iron in Jarosite? A +2 B −2 C +3 D −3 20 A part of the Periodic Table is shown below. P, Q, R, S and T do not represent the actual symbols of the elements. Group I II III IV V VI VII 0 1 P period 2 Q R S 3 T Which statement is correct? A T is a strong oxidising agent. B R forms an ionic compound with S. C P has eight electrons in its outermost shell. D The metallic character of the elements in period 2 increases from Q to S. 21 Rubidium, Rb, is an element in the same group of the Periodic Table as lithium, sodium and potassium. Which statement about rubidium is correct? A It forms an insoluble hydroxide. B Its melting point is lower than lithium. C It reacts slowly with water at room temperature. D