2023 ESSS Chem Prelims P1

CHEMISTRY 6092/01 Paper 1 Multiple Choice Tuesday 1 hour 12 September 2023 0800 – 0900 Additional Materials: Multiple Choice Answer Sheet ___________________________________________________________________ READ THESE INSTRUCTIONS FIRST This question booklet consists of 17 printed pages including the cover page. East Spring Secondary School Towards Excellence and Success Preliminary Examination 2023 Secondary 4 Express Name: …………………………………………………………………………………….… ( ) Class: ……………… Write in soft pencil. Do not use staples, paper clips, glue or correction fluid. Write your name, class, index number on the Answer Sheet 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 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 page 17. The use of an approved scientific calculation is expected, where appropriate.

2 1 The diagram below shows the setup for a chemical reaction which produces a gas. The gas is then dried and collected. What could the gas be? A sulfur dioxide B carbon dioxide C oxygen D hydrogen 2 The cooling curve below shows how the temperature of a gaseous substance changes with time as it is cooled. What is the state of the substance at 25°C? A gas-liquid mixture B liquid C liquid-solid mixture D solid

3 3 The set–up below shows how the relative rate of diffusion of gas X and Y can be determined. The water level at Z does not move. Which of the following could be gas X and gas Y? X Y A carbon monoxide carbon dioxide B ethene nitrogen C carbon dioxide sulfur dioxide D sulfur dioxide ammonia 4 When aqueous sodium hydroxide is warmed with substance R, a white precipitate that is soluble in excess sodium hydroxide was formed. Then, when a piece of aluminium foil is added to the mixture, a colourless and pungent gas is evolved. The gas turns moist red litmus paper blue. Which of the following could substance R be? A ammonium chloride B ammonium nitrate C calcium chloride D zinc nitrate 5 Which statement about methods of purification and analysis is correct? A A liquid that boils over a range of temperatures may still be 100% pure. B An insoluble substance may be purified using simple distillation. C Chromatography may only be used to separate