Copy of VS 2024 Sec 4 Chem Prelim Paper 2

1 ©Victoria School 24/S4PRELIM/6092/2 Class Register Number Name 6092/02 CHEMISTRY 24/S4Prelim/6092/2 PAPER 2 Tuesday 27 August 2024 1 hour 45 minutes VICTORIA SCHOOL VICTORIA SCHOOL VICTORIA SCHOOL VICTORIA SCHOOL VICTORIA SCHOOL VICTORIA SCHOOL VICTORIA SCHOOL VICTORIA SCHOOL VICTORIA VICTORIA SCHOOL VICTORIA SCHOOL VICTORIA SCHOOL VICTORIA SCHOOL VICTORIA SCHOOL VICTORIA SCHOOL VICTORIA SCHOOL VICTORIA SCHOOL VICTORIA VICTORIA SCHOOL VICTORIA SCHOOL VICTORIA SCHOOL VICTORIA SCHOOL VICTORIA SCHOOL VICTORIA SCHOOL VICTORIA SCHOOL VICTORIA SCHOOL VICTORIA VICTORIA SCHOOL VICTORIA SCHOOL VICTORIA SCHOOL VICTORIA SCHOOL VICTORIA SCHOOL VICTORIA SCHOOL VICTORIA SCHOOL VICTORIA SCHOOL VICTORIA VICTORIA SCHOOL PRELIMINARY EXAMINATION SECONDARY FOUR READ THESE INSTRUCTIONS FIRST Write your name, class and index number on all the work you hand in. Write in dark blue or black pen. You may use a HB pencil for any diagrams or graphs. Do not use staples, paper clips, glue or correction fluid. Section A Answer all questions. Write your answers in the spaces provided. Section B Answer one question. Write your answers in the spaces provided. The number of marks is given in brackets [ ] at the end of each question or part question. A copy of the Periodic Table is printed on page 25. The use of an approved scientific calculator is expected, where appropriate. This question paper consists of 25 printed pages, including the cover page. [Turn Over Section A / 70 Section B / 10 Total / 80 Deductions Presentation Significant Figures Units

2 ©Victoria School 24/S4PRELIM/6092/2 Section A (70 marks) Answer all the questions in this section in the spaces provided. A1 Read the clues below to fill in the crossword puzzle. The first one has been done for you. Across (1) inventor of the Periodic Table (2) the particle formed when an atom with proton number 9 is ionised Down (3) the reaction of steam with ethene is an example of an ……………………………reaction (4) steel is an example of an …………………………… (5) the method used to separate a solid sample of iodine and sodium chloride (6) pure substances have a …………………………… melting point [5] [Total:5]

3 ©Victoria School 24/S4PRELIM/6092/2 A2 Some elements burn in air to form oxides. In an experiment, sodium was burnt in a sealed container. The products were then added to a flask containing a solution of Universal Indicator. In a second experiment, the reaction was repeated with burning carbon instead of sodium. (a) State what you would observe with the Universal Indicator in each experiment. experiment using sodium: ……………………………………………………………………… experiment using carbon: ……………………………………………………………………[1] (b) Sodium oxide forms during the first experiment. Draw a ‘dot-and-cross’ diagram to show the arrangement of outer shell electrons in the compound of sodium oxide. [2] (c) In another experiment, 2.30 g of sodium was combusted. Table 2.1 shows the mass of the flask and contents before and after the experiment. Table 2.1 mass of flask and contents at start / g 94.50 mass of flask and contents at end / g 94.82 Calculate the percentage yield of sodium oxide. [3] [Total: 6]

4 ©Victoria School 24/S4PRELIM/6092/2 A3 Carbon monoxide is used to make phosgene, COC l2, which is an important reactant in industries to make polymers, dyes and pharmaceuticals. Phosgene was first made in 1812 by using a photochemical reaction in which a mixture of carbon monoxide and chlorine was exposed to bright sunlight. This reaction is exothermic. CO + Cl2 ⇌ COCl2 (a) (i) Explain, in terms of bond breaking and bond making, why the formation of phosgene is an exothermic reaction. …………………………………………………………………………………………....... …………………………………………………………………………………………....... …………………………………………………………………………………………...[2] (ii) Explain, in terms of oxidation state, if the formation of phosgene is a redox reaction. …………………………………………………………………………………………....... …………………………………………………………………………………………....... …………………………………………………………………………………………...[2] (b) Fig. 3.1 below shows the heating curve of phosgene. Fig. 3.1 Describe the changes in the arrangement and movement of the molecules of phosgene when the temperature is increased from –128 °C to –108 °C. ………………………………………………………………………………………………....... ………………………………………………………………………………………………....... ………………………………………………………………………………………………....... ………………………………………………………………………………………………...[2] [Total: 6] temperature / °C 0 -118 time / s 8

5 ©Victoria School 24/S4PRELIM/6092/2 A4 Catalysis is the increase in rate of a chemical reaction due to an added substance known as a catalyst. Catalysts generally react with one or more reactants to form intermediates that subsequently give the final reaction product. (a) Catalysts are often expensive. Explain why it is still economically viable to use them. ……………………………………………………………………………………………………... ……………………………………………………………………………………………………... ……..……………………………………………………………………………………………[2] (b) Fig. 4.1 below shows a range of industrial catalysts in pellet form. Fig. 4.1 Explain why the catalysts are supplied in pellet form. Use ideas about particles in your answer. ……………………………………………………………………………………………………... ……………………………………………………………………………………………………... ……………………………………………………………………………………………………... …………………………………………………………………………………………………[2]

6 ©Victoria School 24/S4PRELIM/6092/2 (c) Naphthalene (C10H8) reacts with ethanoyl chloride (CH 3COCl) in the presence of a catalyst to form acetylnaphthalene (C12H10O) and hydrogen chloride through a two-step reaction. Fig. 4.2 below shows the energy profile diagram for the catalysed reaction. Fig. 4.2 (i) The uncatalysed reaction takes place in a single step. On Fig. 4.2, sketch the energy change graph for the uncatalysed reaction. [1] energy / kJ progress of reaction naphthalene + ethanoyl chloride acetylnaphthalene + hydrogen chloride

7 ©Victoria School 24/S4PRELIM/6092/2 (d) Ethanoyl chloride is an example of an acyl chloride. Acyl chlorides react with alcohols , in a similar manner to carboxylic acids , to produce esters. The 2 main differences are: • The reaction is irreversible. • Hydrogen chloride is removed instead of water. The structure of ethanoyl chloride is shown below. (i) Name the ester produced when ethanoyl chloride reacts with methanol. …………………………………………………………………………………………[1] (ii) Write a chemical equation for the above reaction, showing all organic substances as full structural formula. [2] [Total: 8]

8 ©Victoria School 24/S4PRELIM/6092/2 A5 The structure of substance X is shown below. Substance X undergoes condensation polymerisation with diaminobutane (H2N(CH2)4NH2). (a) Draw the structure of the polymer formed when substance X reacts with diaminobutane. [1] (b) Substance X can also undergo addition polymerisation. (i) Draw the repeating unit of the polymer formed. [1] (ii) State one difference between the reaction in (a) and the reaction in (b)(i). ………………………………………………………………………………………………. ……………………………………………………………………………………………[1]

9 ©Victoria School 24/S4PRELIM/6092/2 (c) Draw an isomer of diaminobutane (H2N(CH2)4NH2) that still can undergo condensation polymerisation with substance X. [1] [Total:4]

10 ©Victoria School 24/S4PRELIM/6092/2 A6 Nicotine is a highly addictive organic chemical produced naturally in the tobacco