2025 AES 5086 5088 Sc(Chem) Prelim P3

Name: …………………………………………. ( ) Class: ………………….. [Turn over ASSUMPTION ENGLISH SCHOOL PRELIMINARY EXAMINATION 2025 SCIENCE (CHEMISTRY) 5086 / 03 5088 / 03 ASSUMPTION ENGLISH SCHOOL ASSUMPTION ENGLISH SCHOOL ASSUMPTION ENGLISH SCHOOL ASSUMPTION ENGLISH SCHOOL ASSUMPTION ENGLISH SCHOOL ASSUMPTION ENGLISH SCHOOL ASSUMPTION ENGLISH SCHOOL ASSUMPTION ENGLISH SCHOOL ASSUMPTION ENGLISH SCHOOL ASSUMPTION ENGLISH SCHOOL ASSUMPTION ENGLISH SCHOOL ASSUMPTION ENGLISH SCHOOL ASSUMPTION ENGLISH SCHOOL ASSUMPTION ENGLISH SCHOOL ASSUMPTION ENGLISH SCHOOL ASSUMPTION ENGLISH SCHOOL ASSUMPTION ENGLISH SCHOOL ASSUMPTION ENGLISH SCHOOL ASSUMPTION ENGLISH SCHOOL ASSUMPTION ENGLISH SCHOOL LEVEL: Sec 4 Express / Sec 5 Normal (Academic) DATE : 29 August 2025 CLASS(ES): Sec 4/2, 4/3, 4/5 SBB, 5/1 DURATION : 1 hour 15 minutes Additional Materials Provided: NIL INSTRUCTIONS TO CANDIDATES Do not open this booklet until you are told to do so. Write your NAME, CLASS and INDEX NUMBER at the top of this page. This paper consists of 2 sections. Section A (55 marks) Answer all questions. Write your answers in the spaces provided on the question paper. Section B (10 marks) Answer one question. Write your answers in the spaces provided on the question paper. The number of marks is given in brackets [ ] at the end of each question or part question. A copy of the Data Sheet is printed on page 16. A copy of the Periodic Table is printed on page 17. The use of an approved scientific calculator is expected, where appropriate. For Examiner’s use: Section A / 55 Section B / 10 Paper 3 / 65 Paper 1 / 20 Paper 5 / 15 Total / 100 This question paper consists of 17 printed pages including this page.

2 5086/5088/03/4E/5N/PRELIM/25 Section A Answer all the questions in the spaces provided. 1 Choose from the following substances to answer the questions. ammonia carbon monoxide silver sulfate aluminium oxide copper sulfur calcium hydroxide methane sulfur dioxide Each substance may be used once, more than once or not at all. Identify a substance which (a) is a toxic gas that combines with haemoglobin in red blood cells, ……………………………………………………………………………………. [1] (b) is a gas that contributes to the formation of acid rain, ……………………………………………………………………………………. [1] (c) reacts with both acids and alkalis, ……………………………………………………………………………………. [1] (d) is an element which forms X2- ion, ……………………………………………………………………………………. [1] (e) is used to reduce the acidity of soils, ……………………………………………………………………………………. [1] (f) is a greenhouse gas. ……………………………………………………………………………………. [1] [Total: 6]

3 5086/5088/03/4E/5N/PRELIM/25 [Turn over 2 The table below contains details of seven different particles. The letters are not the ch