NYGH 2020-S3EOY-IP Chem P2

Class Register Number Name 南洋女子中学校 NANYANG GIRLS' HIGH SCHOOL End-of-Year Examination 2020 Secondary Three Chemistry Paper 2 Theory Paper 1 hour 45 minutes Wednesday 07 October 2020 0845 - 1030 Additional materials: Writing paper READ THESE INSTRUCTIONS FIRST Do not open this booklet until you are told to do so. Write your name, register number and class in the spaces at the top of this page and on any separate answer paper used. Section A (40 marks) Answer all questions. Write your answers in the spaces provided on the question paper. Section B (30 marks) Answer all questions including questions B6, B7 and B8 Either or B8 Or. Write your answers on the separate writing paper provided. At the end of the examination, 1. Fasten all your work securely together; 2. Circle B8 Either (for Either) or B8 Or (for Or) in the grid on the right to indicate the question you have answered; 3. Hand in Section A and Section B separately. INFORMATION FOR CANDIDATES The intended number of marks is given in the brackets [ ] at the end of each question or part question. You are advised to spend no longer than 60 minutes on Section A and no longer than 45 minutes on Section B. The use of approved scientific calculators is allowed. A copy of the periodic table is found on page 15. Paper 1 / 30 Paper 2 Section A / 40 B6 / 10 B7 / 10 B8 Either / B8 Or / 10 Total / 100 Setters: NHK/ OWJ This document consists of 14 printed pages and 2 blank pages. NANYANG GIRLS’ HIGH SCHOOL [Turn over

2020 End-of-Year Examination Secondary Three 2 Nanyang Girls’ High School Setters: NHK/ OWJ Chemistry/ Paper 2 Section A (40 marks) Answer all questions. Write your answers in the spaces provided. A1 Ammonium chloride is a white crystalline salt that is used mainly as a fertiliser and a flavouring agent. It is separated from a mixture with the setup below. (a) What is the property of ammonium chloride that makes it suitable to be separated from the mixture with the setup above? [1] (b) The table below shows some properties of ammonium chloride. decomposition temperature 338 oC solubility highly soluble in water electrical conductivity conducts electricity in aqueous state (i) State the type of bonding(s) found in ammonium chloride. [1] (ii) Ammonium chloride decomposes to form hydrogen chloride gas. Draw a dot-and-cross diagram to show the bonding in hydrogen chloride gas, showing only the valence electrons. [2] cotton plug pure ammonium chloride mixture inverted glass funnel Bunsen burner tripod stand

2020 End-of-Year Examination Secondary Three 3 Nanyang Girls’ High School Setters: NHK/ OWJ Chemistry/ Paper 2 [Turn Over (c) Plugs of cotton wool soaked respectively in concentrated aqueous ammonia and concentrated hydrochloric acid are inserted at the same time into the open ends of a horizontal tube as shown in the diagram below. The ends ar