2022 ZHSS Chem Prelims P1

1 [Turn over ZHONGHUA SECONDARY SCHOOL PRELIMINARY EXAMINATION 2022 SECONDARY 4E Candidate’s Name Class Register Number 4E CHEMISTRY 6092/01 26 Aug 2022 1 hour Additional Materials: OTAS READ THESE INSTRUCTIONS FIRST Write in soft pencil. Do not use staples, paper clips, highlighters, glue or correction fluid. Write your name, index number and class on the OTAS in the spaces provided. There are forty 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 OTAS. Read the instructions on the OTAS very carefully. Each correct answer will score one mark. A mark will not be deducted for a wrong answer. Any rough working should be done in this booklet. A copy of the Periodic Table is printed on page 17. Setter: Ms Ong Lay Hong Vetter: Ms Julia Yeo This document consists of 17 printed pages, including this cover page. ���

2 [Turn over 1 The apparatus shown in the diagram was set up. The water level at X gradually moved up above the mark. When the water levels were observed to have stopped moving, the beaker of carbon dioxide were removed. The water level at X then fell below the mark before returning back to the mark. Which of the following is likely to explain why the water level at X fell below the mark? A Air inside the porous jar diffused out faster than the carbon dioxide. B Carbon dioxide in the porous jar diffused out slower than air which diffused in. C Air around the porous jar diffused in slower than the carbon dioxide diffused out. D Carbon dioxide around the porous jar continued to diffuse in faster than air diffused out. 2 The urine samples of athletes are routinely checked for the presence of drugs which can enhance their performance. The following diagram (not drawn to scale) shows a chromatogram of the urine sample of an athlete. He is suspected to have taken a banned drug with a retention value, Rf of 0.60. Which position, A, B, C or D indicates the presence of this drug? X carbon dioxide porous jar water air ���

3 [Turn over 3 The diagram below shows the fractional distillation of two liquids, R and S. R has a boiling point of 80 oC and S has a boiling point of 110 oC. Which statement(s) about the experiment is/are correct when the thermometer shows 80 oC? 1 The liquid left in the flask contains more S than R. 2 The vapour at point Y only contains R. 3 The temperature at X is higher than the temperature at Y. A 1 only B 1 and 2 C 2 and 3 D 1, 2 and 3 4 The diagram shows the outer shell electron arrangement of a molecule of a compound made up of the elements Z and Y. What is the formula of the compound formed b