WDL 4NA Science Chemistry P4 Question Booklet 2023

5105 and 5107/04/Prelim/2023 NORMAL (ACADEMIC) NORMAL (ACADEMIC) NORMAL (ACADEMIC) Name: ........................................................................ ( ) Class: ................ WOODLANDS SECONDARY SCHOOL PRELIMINARY EXAMINATIONS 2023 Level: Secondary Four Normal (Academic) Marks: 30 Subject: Science (Chemistry) Day: Wednesday Paper: 5105/04 and 5107/04 Date: 2 August 2023 Duration: 1 hour 15 minutes (Papers 3 and 4) Time: 1145 – 1300 READ THESE INSTRUCTIONS FIRST Write your class, index number and name on all the work that you hand in. Write in dark blue or black pen on both sides of the paper. You may use an HB pencil for any diagrams or graphs. Do not use staples, paper clips, glue or correction fluid. Answer all questions in Section A and any two questions in Section B. The use of an approved scientific calculator is expected, where appropriate. In calculations, you should show all the steps in your working, giving your answer in 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 page 12. At the end of the examination hand in your answers to Paper 3 and Paper 4 separately. The number of marks is given in brackets [ ] at the end of each question or part question. DO NOT TURN THE PAGE UNTIL YOU ARE TOLD TO DO SO. This document consists of 11 printed pages and 1 blank page. FOR EXAMINER’S USE Paper 3 Paper 4 Total /20 Section A /14 /30 /50 Section B /16

2 5105 and 5107/04/Prelim/2023 NORMAL (ACADEMIC) NORMAL (ACADEMIC) NORMAL (ACADEMIC) Section A Answer all questions in this section in the spaces provided. 1 The following table shows some substances, with their chemical formulae. substance chemical formula ammonia NH3 hydrogen H2 potassium hydroxide KOH propane C3H8 propene C3H6 sulfuric acid H2SO4 From the table, identify one substance which (a) decolourises reddish-brown aqueous bromine, ……………………………………………………………………………………..… [1] (b) extinguishes the flame on a lighted splint with a ‘pop’ sound, ……………………………………………………………………………………..… [1] (c) reacts with ammonium sulfate to produce ammonia gas, (d) ……………………………………………………………………………………..… [1] turns Universal Indicator red. ……………………………………………………………………………………….. [1]

3 5105 and 5107/04/Prelim/2023 NORMAL (ACADEMIC) NORMAL (ACADEMIC) NORMAL (ACADEMIC) 2 (a) Name the homologous series whose members undergo substitution reaction, and give the general formula for its members. homologous series: ……………………………………………………… [1] general formula: …………………………………………………………. [1] (b) State the name of the third member of the homologous series in part (a). Calculate its relative molecular