2023 BBSS Chem Prelims P1

Name: ………………………………………. Index no: ……… Class: ……..… READ THESE INSTRUCTIONS FIRST Write in soft pencil. Do not use staples, paper clips, glue or correction fluid. Write your name, index number and class on the Answer Sheet, and in the spaces provided at the top of this page. 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 15. The use of an approved scientific calculator is expected, where appropriate. This document consists of 15 printed pages. Bukit Batok Secondary School ‘O’ LEVEL PRELIMINARY EXAMINATIONS 2023 SECONDARY 4 EXPRESS CHEMISTRY Paper 1 Multiple Choice 6092/01 23 AUG 2023 1105 – 1205 1 hour Additional Materials: Multiple Choice Answer Sheet

BBSS/OPrelims/2023/Sec4E/6092/1 2 Applying past knowledge to new situations 1 A student studied the rate of reaction when 0.05 g of magnesium was reacted with excess acid at room temperature and pressure. Which apparatus would be suitable to measure the volume of gas produced at different times during the experiment? 1 a 50 cm3 gas syringe 2 an inverted 100 cm3 measuring cylinder filled with water 3 an inverted gas jar filled with water A 1 only B 2 only C 2 and 3 only D 1, 2 and 3 2 Under the same conditions, which of the following gases would diffuse at the same rate as ethene, C2H4? 1 carbon monoxide 2 carbon dioxide 3 ethane 4 nitrogen A 1 and 3 B 1 and 4 C 2 and 3 D 2 and 4 3 The boiling points of four substances found in air are given in the table. Air is cooled to –190 °C such that some substances condense into liquid. When the temperature is then raised, which liquid would turn into a gas first? substance boiling point /°C A B C D argon carbon dioxide nitrogen oxygen –186 –78 (sublimes) –196 –183

BBSS/OPrelims/2023/Sec4E/6092/1 3 Applying past knowledge to new situations 4 Oxygen was prepared by the decomposition of hydrogen peroxide in the presence of manganese(IV) oxide according to the equation: 2 H2O2 à 2 H2 + O2 The oxygen was collected using the set-up shown in the diagram. Which substance contaminated the first few jars of oxygen collected? A hydrogen B hydrogen peroxide C manganese(IV) oxide D nitrogen 5 Solid P conducts electricity and has a high melting point. When solid P is warmed with excess dilute hydrochloric acid, it partially dissolves leaving behind a residue. What is P? A brass B copper(II) oxide C graphite D iron aqueous hydrogen peroxide aqueous hydrogen peroxide oxygen gas jar water trough manganese(IV) oxide

B