DHS_H1_CHEM_P1_QP_with_answer_key

This document consists of 13 printed pages and 1 blank page. © DHS 2018 8873/01 [Turn Over Name: Index Number: Class: DUNMAN HIGH SCHOOL Preliminary Examination 2018 Year 6 H1 CHEMISTRY 8873/01 Paper 1 Multiple Choice 24 September 2018 1 hour Additional Materials: Data Booklet Optical Mark Sheet INSTRUCTIONS TO CANDIDATES 1 Write your name, index number and class on this question paper and the OTAS Mark Sheet. 2 There are thirty 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 Optical Mark Sheet. 3 Each correct answer will score one mark. A mark will not be deducted for wrong answer. 4 Any rough working should be done in this booklet. 5 The use of an approved scientific calculator is expected, where appropriate. 6 On the OTAS Mark Sheet, please shade the code as “Class/Index number”. For illustration only: A student from class 6C38, with index number 02, should shade “3802”. 3 8 0 2

2 © DHS 2018 8873/01 1 Which option contains one mole of the stated particles? Note that D = H1 2 . A carbonate ions in 60 g of sodium carbonate B neutrons in 1.8 g of heavy water, D2O C electrons in 0.1 mol of OH– D oxygen atoms in 11.2 dm3 of O3, under s.t.p 2 NF3 can be obtained from the reaction between ammonia and fluorine gas. 4NH3 + 3F2 → NF3 + 3NH4F Which statement about the reaction is correct? A NH 3 undergoes disproportionation. B The oxidation number of nitrogen in NF3 is +3. C NH3 is a stronger oxidising agent than F2. D One mole of F2 loses two moles of electrons. 3 Use of the Data Booklet is relevant to this question. Which statement regarding 26Mg2+ and 27Al3+ ions is true? 1 26Mg2+ has more protons than 27Al3+. 2 Both ions have more neutrons than protons in their nuclei. 3 Both ions have outer electronic configuration 2s 22p6. 4 Both ions have the same number of neutrons. A 1 and 2 only B 1 and 3 only C 3 and 4 only D 2, 3 and 4 only 4 In which substance must covalent bonds break on melting? A calcium B silicon C sodium carbonate D ice

3 © DHS 2018 8873/01 [Turn Over 5 Valence Shell Electron Pair Repulsion theory can be used to predict the shapes of molecules and ions. Which of the following are the shapes of NO 2 and NO3– respectively? NO2 NO3– A linear trigonal planar B linear trigonal pyramidal C bent trigonal planar D bent trigonal pyramidal 6 Use of the Data Booklet is relevant to this question. Which graph shows the correct trend when the melting points of the oxides of elements Mg, Al, Si and P is plotted against its ionic radius? A Melting point of oxide Ionic radius of element . Al Mg.