plmgs comb chem prelim 2024 paper 3

1 SCIENCE 5105 & 5107/03 Paper 3 Chemistry 30 July 2024 (Taken together with Paper 4) 1 hour 15 mins READ THESE INSTRUCTIONS FIRST Write your name and index number on all the work you hand in. Do not use staples, paper clips, highlighter, glue or correction fluid. The use of an approved scientific calculator is expected, where appropriate. There are twenty questions in this paper. For each question, four possible answers are given. Choose the one you consider correct and record your choice in soft pencil on the separate optical Answer Sheet. You are advised to spend no more than 30 minutes on Paper 3 and 45 minutes on Paper 4. You may proceed to Paper 4 as soon as you have completed Paper 3. The number of marks is given in brackets [ ] at the end of each question or part question. A copy of the Periodic Table is printed on page 10. This document consists of 10 printed pages. CANDIDATE NAME CLASS CLASS INDEX NO CENTRE NUMBER S INDEX NO Paya Lebar Methodist Girls’ School (Secondary) Preliminary Examination 2024 Secondary 4 Normal Academic / G2 [Turn over

2 1 A student wishes to add exactly 17.20 cm3 of acid to exactly 25.0 cm3 of an alkali as part of an experiment. Which apparatus should the student use to measure these volumes? acid alkali A burette measuring cylinder B burette pipette C measuring cylinder pipette D pipette burette 2 Lead(II) chloride is an insoluble salt which is formed in the reaction of aqueous lead(II) nitrate with aqueous potassium chloride. How is pure lead(II) chloride obtained after the reaction? A crystallisation → evaporation B evaporation → washing and drying C filtration → evaporation D filtration → washing and drying 3 A new element has seven electrons in its outermost shell. Which statement about the element is correct? A It is monoatomic. B It forms a positive ion, X+. C It forms a diatomic molecule. D It forms covalent compounds with sodium.

3 4 What is the chemical formula of iron(II) sulfate? A FeS B FeSO4 C Fe(SO4)2 D Fe2SO4 5 The nucleon number and proton number of an atom of X and an atom of Y are shown. X Y nucleon number 39 40 proton number 19 18 Which statement about X and Y is correct? A An atom of X has fewer electrons than an atom of Y. B An atom of X has fewer neutrons than an atom of Y. C X is above Y in the same group of the Periodic Table. D X is in the same period in the Periodic Table as Y. 6 The table shows the results of adding dilute hydrochloric acid, HCl, and aqueous sodium hydroxide, NaOH to four metal oxides (A, B, C and D). Which of the metal oxides displays amphoteric properties? addition of dilute HCl addition of aqueous NaOH A no reaction no reaction B no reaction reaction C reaction no rea