2022 SSS Chem Prelims P1

1 SERANGOON SECONDARY SCHOOL PRELIMINARY EXAMINATION SECONDARY 4 EXPRESS CANDIDATE NAME ( ) CLASS CENTRE NUMBER S INDEX NUMBER CHEMISTRY 6092/01 Paper 1 Multiple Choice 24 Aug 2022 1 hour Additional Materials: Multiple Choice Answer Sheet READ THESE INSTRUCTIONS FIRST Write in soft pencil. Do not use staples, paper clips, highlighters, glue or correction fluid. Write your name, class and index number on the Answer Sheet in the spaces provided unless this has been done for you. 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 Answer Sheet. Read the instructions on the Answer Sheet 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 the last page. The use of an approved scientific calculator is expected, where appropriate. This question paper consists of 19 printed pages, including this cover page. For examiner’s use 40 ���

2 1 25 cm3 of aqueous sodium hydroxide is pipetted into a conical flask and titrated with dilute hydrochloric acid from a burette. How can the accuracy of the titration be improved? I. Rinse the interior of the pipette with aqueous sodium hydroxide. II. Rinse the interior of the pipette with aqueous hydrochloric acid. III. Rinse the interior of the conical flask with aqueous sodium hydroxide. IV. Rinse the interior of the burette with dilute hydrochloric acid. A I and III only B I and IV only C II and III only D I, III and IV 2 The diagram below is a set-up used to obtain carbon monoxide. What is the main purpose of the aqueous sodium hydroxide? A Dry the carbon monoxide. B Remove the carbon dioxide. C Remove the excess acid. D Remove the oxygen present. water aqueous sodium hydroxide carbon monoxide calcium carbonate lumps of charcoal heat dilute hydrochloric acid ���

3 3 Esters can be prepared by reactions of alcohols and carboxylic acids. The yield of these reactions is often low. One way of improving the yield is to remove the ester formed as the reaction proceeds and this can be done by carrying out fractional distillation. Which of the following mixtures will yield an ester as the distillate using this method? A ethanol (B.P: 78oC) ethanoic acid (B.P: 118oC) ethyl ethanoate (B.P: 77oC) B butanol (B.P: 117oC) ethanoic acid (B.P: 118oC) butyl ethanoate (B.P: 128oC) C ethanol (B.P: 78oC) butanoic acid (B.P: 164oC) ethyl butanoate (B.P: 121oC) D methanol (B.P: 65oC) butanoic acid (B.P: 164oC) methyl butanoate (B.P: 102oC) 4 Vitamins are essential nutrients needed in small amounts for various roles in the human body. They are either water-soluble or fat-soluble. A sample of he