EJC Prelim H1 Chemistry Paper 2 Solutions

© EJC [Turn Over EUNOIA JUNIOR COLLEGE JC2 Preliminary Examination 2025 General Certificate of Education Advanced Level Higher 1 CANDIDATE NAME CIVICS GROUP 2 4 – INDEX NUMBER CHEMISTRY Paper 2 Structured Questions 8873/02 02 September 2025 2 hours Candidates answer on the Question Paper Additional Materials: Data Booklet READ THESE INSTRUCTIONS FIRST Do not use paper clips, highlighters, glue or correction fluid. Write your name, civics group, registration 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. Section A Answer all questions. Section B Answer one question. The number of marks is given in brackets [ ] at the end of each question or part question. A Data Booklet is provided. The use of an approved scientific calculator is expected, where appropriate. For Examiner’s Use Section A 1 / 15 2 / 10 3 / 16 4 / 10 5 / 9 Section B 6 / 7 / 20 Total / 80 This document consists of 25 printed pages and 3 blank pages.

2 © EJC 8873/02/J2Prelims/25 For Examiner’s Use Section A Answer all questions in this section. 1 (a) Fig. 1.1 shows the trend for the third ionisation energies of a series of consecutive elements from the second and third period of the Periodic Table. Fig. 1.1 (i) Define the term third ionisation energy, with the aid of an equation for element A. ................................ ................................ ................................ ............................. ................................ ................................ ................................ ............................. ................................ ................................ ................................ ............................. ................................ ................................ ................................ ......................... [2] (ii) Explain the general trend in the 3rd ionisation energy from element C to I. ................................ ................................ ................................ ............................. ................................ ................................ ................................ ............................. ................................ ................................ ................................ ............................. ................................ ................................ ................................ ......................... [2] A B C D E F G H I 3rd ionisation energy element I Energy absorbed to remove 1 mole of electrons from 1 mole of doubly - charged, gaseous cation to form 1 mole of triply -charged, gaseous cation. A2+(g) → A3+(g) + e– 3rd IE generally increases from elements C to I. Nuclear charge increases. Shielding effect remains relatively constant due to same number of qu