AES 4NA Science Chemistry P4 Question Paper 2023

[Turn over Name: ……………………………………………….. ( ) Class: ……... ASSUMPTION ENGLISH SCHOOL PRELIMINARY EXAMINATION 2023 SCIENCE (CHEMISTRY) 5105 / 04 5107 / 04 ASSUMPTION ENGLISH SCHOOL ASSUMPTION ENGLISH SCHOOL ASSUMPTION ENGLISH SCHOOL ASSUMPTION ENGLISH SCHOOL ASSUMPTION ENGLISH SCHOOL ASSUMPTION ENGLISH SCHOOL ASSUMPTION ENGLISH SCHOOL ASSUMPTION ENGLISH SCHOOL ASSUMPTION ENGLISH SCHOOL ASSUMPTION ENGLISH SCHOOL ASSUMPTION ENGLISH SCHOOL ASSUMPTION ENGLISH SCHOOL ASSUMPTION ENGLISH SCHOOL ASSUMPTION ENGLISH SCHOOL ASSUMPTION ENGLISH SCHOOL ASSUMPTION ENGLISH SCHOOL ASSUMPTION ENGLISH SCHOOL ASSUMPTION ENGLISH SCHOOL ASSUMPTION ENGLISH SCHOOL ASSUMPTION ENGLISH SCHOOL LEVEL: Sec 4 Normal (Academic) DATE : 3 August 2023 CLASSES: Sec 4/4, 4/5 and 4/6 SBB DURATION: 1 hour 15 minutes (Papers 3 & 4) Additional Materials provided: NIL INSTRUCTIONS TO CANDIDATES Do not open this booklet until you are told to do so. Write your NAME, INDEX NUMBER and CLASS at the top of this page. Write in dark blue or black pen on both sides of the paper. You may use a soft pencil for any diagrams or graphs. Do not use staples, paper clips, highlighters, glue or correction fluid. Answer all questions in Section A and any two questions in Section B. In calculations, you should show all the steps in your working, giving your answer at each stage. You are advised to spend no longer than 30 minutes on Paper 3. You may proceed to answer Paper 4 as soon as you have completed Paper 3. A copy of the Periodic Table is printed on the last page of Paper 4. At the end of the examination, hand in your OAS paper and Question Papers separately. The number of marks is given in brackets [ ] at the end of each question or part question. For Examiner’s Use Paper 3 Section A Section B Total This question paper consists of 11 printed pages including this page. 14 50 20 16

2 5105/5107/04/4NA/PRELIM/23 Section A [14 marks] Answer all the questions in the spaces provided. 1 A mixture of two miscible substances, methanol and propanol, are to be separated. The boiling points of methanol and propanol are 64 C and 98 C respectively. The mixture is heated in the apparatus shown below. (a) State the use of pieces of solids added to the liquid mixture during the separation. …………………………………………………………………………………….. [1] (b) Which of the two substances will be collected in the beaker first? Explain your answer. …………………………………………………………………………………….. …………………………………………………………………………………….. [1] (c) Describe the arrangement and movement of particles at point X. arrangement……………………………………………………………………… …………………………………………………………………………………….. movement………………………………………………………………………… …………………………………………………………………………………….. [2] thermometer glass beads round bottomed flask liquid mixture with pieces of solid beaker water in water out X

3 5105/5107/04/4NA/PRELIM/23 [Turn over 2 In a titration experiment, potassium chloride is made by reacting hydrochloric acid with potassium hydroxide solution. (a) An indicator is a substance which changes colour depending on whether the solution being tested is acidic or alkaline. The diagram below shows the colour of methyl orange at different pH. State the colour observed when a few drops of methyl orange is added to potassium hydroxide in the conical flask. …………………………………………………………………………………….. [1] (b) Write the ionic equation for the reaction between hydrochloric acid and potassium hydroxide. …………………………………………………………………………………….. [1] (c) Suggest another chemical that is safe to react with hydrochloric acid to form potassium chloride when potassium hydroxide is no longer available. …………………………………………………………………………………….. [1] burette conical flask hydrochloric acid potassium hydroxide with methyl orange indicator

4 5105/5107/04/4NA/PRELIM/23 3 The diagram represents a type of mixture that can be made from iron. This type of mixture is often used in making bridges. (a) Give a name to this type of mixture. …………………………………………………………………………………….. [1] (b) Using your understanding of the diagram above, explain why this type of mixture is used in making bridges. …………………………………………………………………………………….. …………………………………………………………………………………….. …………………………………………………………………………………….. …………………………………………………………………………………….. [2] (c) This mixture is used to make food containers and it is usually coated with a thin layer of tin to prevent rusting. Name the element and the compound which react together with iron to form rust. element..……………………….….. compound……………………….... [1] key iron atom carbon atom

5 5105/5107/04/4NA/PRELIM/23 [Turn over 4 Equal amounts of four different powdered metals , P, Q, R and S, were added separately to equal volumes of dilute nitric acid. The graph shows the volume of hydrogen gas collected at the end of five minutes. (a) Describe a test you can perform to test for hydrogen gas. test.………………………………………………………………………………... observation……………………………………………………………………….. [1] (b) Based on the information, complete the table to match metals P, Q, R or S to their possible identities. metal P, Q, R or S magnesium zinc iron copper [2] metal Q volume of gas collected / cm3 P R S

6 5105/5107/04/4NA/PRELIM/23 Section B [16 marks] Answer any two questions from this section in the spaces provided. 5 The table gives information about sodium, chlorine and hydrogen atoms. sodium atom chlorine atom hydrogen atom number of protons 11 17 number of electrons 17 arrangement of electrons 2.8.1 1 (a) Complete the table. [2] (b) State the location of the protons and the electrons in a chlorine atom. proton………………………………………………… electron.……………………………………………… [1] (c) Sodium chloride solid can be made by burning sodium metal in chlorine gas. Write a balanced chemical equation, including state symbols, for this reaction. …………………………………………………………………………………….. [2] (d) Explain why sodium chloride must be dissolved in water first before it can conduct electricity. …………………………………………………………………………………….. …………………………………………………………………………………….. [1] (e) Hydrogen chloride gas, HCl, is made by reacting hydrogen with chlorine. Draw a ‘dot and cross’ diagram of a HCl molecule. Your diagram should show only the outer shell electrons. [2]

7 5105/5107/04/4NA/PRELIM/23 [Turn over 6 Excess metal carbonate, XCO3, was added to 100 cm3 of dilute sulfuric acid as shown in the diagram. The volume of gas Y produced at room conditions was measured every minute. The results are shown in the table: time / min 0.0 1.0 2.0 3.0 4.0 5.0 6.0 7.0 volume of gas Y / cm3 0.0 20.0 33.0 52.0 58.0 60.0 60.0 (a) (i) Plot a graph of volume of gas Y against time, marking each point with a cross (x). Draw a curve of best fit, taking into account all your plotted points. [2] volume of gas Y / cm3 time / min conical flask gas syringe dilute sulfuric acid retort stand excess metal carbonate stopwatch

8 5105/5107/04/4NA/PRELIM/23 (ii) From your graph determine the total volume of gas Y collected after 3 minutes.