ASR 2020 J2Prelim H2Chem P2 QP

ASRJC JC2 PRELIM 2020 9729/02/H2 [Turn over ANDERSON SERANGOON JUNIOR COLLEGE 2020 PRELIMINARY EXAMINATION NAME:______________________________ ( ) CLASS: 20 /____ CHEMISTRY 9729/02 Paper 2 Structured Questions 15 September 2020 2 hours Candidates answer on the Question Paper. Additional Materials: Data Booklet READ THESE INSTRUCTIONS FIRST Write your name, class and register number on all the work you hand in. Write in dark blue or black pen. 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 the spaces provided on the Question Paper. The use of an approved scientific calculator is expected, where appropriate. A Data Booklet is provided. At the end of the examination, fasten all your work securely together. The number of marks is given in brackets [ ] at the end of each question or part question. For Examiner’s Use Paper 2 1 / 13 2 / 14 3 / 12 4 / 10 5 / 14 6 / 12 Total / 75 This document consists of 23 printed pages and 1 blank page.

2 ASRJC JC2 PRELIM 2020 9729/02/H2 Answer all the questions in the spaces provided. 1 One early nineteenth century Periodic Table had copper placed in the same group as potassium because they both formed +1 ions. (a) State the full electronic configurations of potassium and copper atoms. …….……………………………………………………………………………………………………. …….…………………………………………………………………………………………………[1] (b) (i) The mass of an atom is the sum of the masses of all subatomic particles it contains. Calculate the mass, in kg, of one atom of 64 29Cu . Quote relevant values from the Data Booklet and give your answer to three significant figures. [2] (ii) During the process of ionisation, a Cu atom loses an electron. Cu(g)  Cu+(g) + e− State the electronic configuration of Cu+. Explain your answer. 1s2 .……………………………………………………………………………………………… explanation ..…………………………………………………………………………………… …………………………………………………………………………………………………[2]

3 ASRJC JC2 PRELIM 2020 9729/02/H2 [Turn over (iii) On the Cartesian axes given in Fig . 1.1, sketch the shape of the following three 3d orbitals found in copper atom. Fig. 1.1 [2] x y z x y z x y z 3dxz 3dz2 3dx2–y2

4 ASRJC JC2 PRELIM 2020 9729/02/H2 (c) (i) Define the term standard enthalpy change of formation. …………………………………………………………………………………………………… …………………………………………………………………………………………………… …………………………………………………………………………………………………[1] (ii) Table 1.1 enthalpy change value / kJ mol–1 standard enthalpy chang