2020 SNGS Prelim P1

This document consists of 20 printed pages. [Turn over Name: _______________________________ ( ) Class:___________ PRELIMINARY EXAMINATION GENERAL CERTIFICATION OF EDUCATION ORDINARY LEVEL __________________________________________________________________________ CHEMISTRY 6092/01 Paper 1 Multiple Choice 2 September 2020 1 hour Additional Materials: Multiple Choice Answer Sheet __________________________________________________________________________ READ THESE INSTRUCTIONS FIRST Write your name, register number and class on the Answer Sheet using a soft pencil. There are forty questions in this paper. Answer all questions. For each question there are four possible answers A, B, C and D. Choose the correct answer and record the corresponding letter using a soft pencil on the separate Answer Sheet. Amendments may be done using a soft eraser. Each correct answer will score one mark. A mark will not be deducted for a wrong answer. The use of an approved scientific calculator is expected, where appropriate. A copy of Periodic Table is provided on page 2. The total number of marks for this paper is 40. For Examiner’s Use Total (40)

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3 1 The diagram below shows the fractional distillation of two liquids R and S. R has a boiling point of 80 °C and S has a boiling point of 120 °C. Which statement(s) about the experiment is/are correct? 1. At 70 °C, the vapour at point X contains more R than S. 2. The temperature at point Y is always higher than the temperature at point X. 3. At 90 °C, the liquid remaining in the round bottom flask contains S only. A 1 only B 2 only C 1 and 2 D 1, 2 and 3

4 2 A bottle of copper(II) oxide has been contaminated with some solid potassium chloride. How can the potassium chloride be removed from copper(II) oxide? A Add water to the mixture and filter. B Add dilute acid to the mixture and filter. C Add aqueous silver nitrate to the mixture and filter. D Heat the mixture and allow it to cool. 3 Food dyes 1 and 2 may contain the three harmful substances X, Y and Z. Two chromatograms are developed, one using water as the solvent, and the other using ethanol. The results are shown in the diagram below. Which of the following statement(s) is/are correct? 1. There is a component in food dye 1 that is insoluble in water but soluble in ethanol. 2. The component in Z is more soluble in water than in ethanol. 3. Food dye 2 does not contain any of the three harmful substance. A 1 only B 2 only C 1 and 2 D 1 and 3

5 4 Element X has n protons and forms ions with charge of -2. Element Y has (n+1) protons. What could be formed when element X reacts with element Y? A an ionic compound with formula X2Y B an ionic compound with formula XY2 C a covalent compound with formula X2Y D a covalent compound with formula XY2 5 The apparatus shown can be used to study the diffusion of gases. Two beakers containing gas P were placed over two porous pots containing gases Q and R respectively. The results are shown. What is the correct order of the relative molecular mass of gases P, Q and R? highest Mr lowest Mr A R P Q B R Q P C Q P R D P Q R beaker beaker

6 6 A sample of gas is cooled and the temperature change is as shown. Which of the following describes the arrangement and movement of the particles in the region R to S? arrangement of particles movement of particles A close together in orderly arrangement vibrating about fixed position B close together in orderly arrangement moving at high speeds C close together in disorderly arrangement sliding and rolling over each other D close together in disorderly arrangement vibrating about fixed position 7 Which of the following statements describing the product formed from calcium and chlorine are correct? 1. The product has a fixed composition by mass of its elements. 2. The product has the smell of chlorine and the colour of calcium. 3. The product can be separated into simpler substances by physical means. 4. The product melts at a sharp temperature. A 1 and 2 B 1 and 4 C 2 and 3 D 3 and 4

7 8 Gallium oxide has the formula Ga2O3 while rubidium phosphate has the formula Rb3PO4. What is the formula of gallium phosphate? A GaPO4 B Ga2PO4 C Ga3PO4 D Ga2(PO4)3 9 At room temperature, tin exists as white tin which has a metallic structure. Below 13°C, white tin changes to grey tin which has a giant covalen t structure similar to that of diamond. Which of the statements is correct? A Both types of tin can conduct electricity. B Both types of tin are soft and malleable. C White tin is hard while grey tin is soft. D White tin can conduct electricity while grey tin cannot. 10 A sample of 0.025 mol of the chloride of element Z was dissolved in 500 cm 3 of distilled water. 12.5 cm 3 of this solution reacted completely with 25 .0 cm3 of 0.1 mol/dm 3 silver nitrate solution. What is the most likely formula of the chloride? A ZCl B ZCl2 C ZCl3 D ZCl4

8 11 How many carbon atoms are present in 18 g of glucose, C 6H12O6, where 1 mole of any substance contains 6 × 1023 particles? A 6.0 × 1022 B 3.6 × 1023 C 6.0 × 1023 D 3.6 × 1024 12 Carbon disulfide, CS2, is a volatile flammable liquid. On combustion at room temperature and pressure, CS2 reacts as follows: CS2 (g) + 3O2 (g) → CO2 (g) + 2SO2 (g) A 20 cm3 sample of CS2 vapour was ignited with 100 cm3 of oxygen. The final volume of gases after combustion is treated with an excess of an aqueous alkali. What is the percentage volume of gas that dissolves in the alkali? A 20% B 40% C 60% D 80% 13 Calcium is a mineral that the body needs for numerous functions, including building and maintaining bones and teeth. When 50 g of bone is strongly heated in excess air, 14 g of calcium oxide was obtained. What is the percentage by mass of calcium in the bone? A 10% B 14% C 20% D 28%

9 14 Which of the following statements is correct about the elements going from left to right in period 3 of the Periodic Table? A The metallic properties of the elements increases. B The tendency of the elements forming positive ions increases. C The nature of the oxides of the elements changes from acidic to amphoteric to basic. D The nature of the elements changes from strong reducing agents to strong oxidising agents. 15 An element W combines with oxygen to form two gases with the formulae WO and WO2. WO does not react with acids nor alkalis while WO2 reacts only with alkalis to form salt and water. What does this suggest about element W? A It is a halogen. B It is an alkali metal. C It is a metal in Group II. D It is a non-metal in Group V. 16 Caesium is an element in Group I of the Periodic Table. The following statements are made about caesium. 1. Caesium is soft and can be cut easily with a knife. 2. Caesium conducts electricity only in the solid state. 3. Caesium is a stronger reducing agent than rubidium. 4. Caesium reacts explosively with water to form an acidic solution. Which statements about caesium are true? A 1 and 2 B 1 and 3 C 1, 2 and 3 D 2, 3 and 4

10 17 Gas X is bubbled through aqueous sodium chloride and sodium iodide respectively. The following observations are made. sodium chloride: no visible change sodium iodide: cololurless solution turns brown spontaneously What is the identity of X? A ammonia B chlorine C fluorine D hydrogen 18 In which of the following reactions does hydrogen behave as an oxidising agent? A H2 + Cl2 → 2HCl B 2Na + H2 → 2NaH C N2 + 3H2 → 2NH3 D C2H4 + H2 → C2H6 19 The reaction between copper and