AQA GCSE COMBINED SCIENCE: TRILOGY 8464/C/2F Foundation Tier Chemistry Paper 2F Question Paper + Mark scheme [MERGED] June 2022 *jun228464c2F01* IB/M/Jun22/E11 8464/C/2F For Examiner’s Use Question Mark 1

AQA GCSE COMBINED SCIENCE: TRILOGY 8464/C/2F Foundation Tier Chemistry Paper 2F Question Paper + Mark scheme [MERGED] June 2022 *junc2F01* IB/M/Jun22/E11 8464/C/2F For Examiner’s Use Question Mark 1 2 3 4 5 6 7 TOTAL Time allowed: 1 hour 15 minutes Materials For this paper you must have: • a ruler • a scientific calculator • the periodic table (enclosed). Instructions • Use black ink or black ball-point pen. • Pencil should only be used for drawing. • Fill in the boxes at the top of this page. • Answer all questions in the spaces provided. • If you need extra space for your answer(s), use the lined pages at the end of this book. Write the question number against your answer(s). • Do all rough work in this book. Cross through any work you do not want to be marked. • In all calculations, show clearly how you work out your answer. Information • The maximum mark for this paper is 70. • The marks for questions are shown in brackets. • You are expected to use a calculator where appropriate. • You are reminded of the need for good English and clear presentation in your answers. Please write clearly in block capitals. Centre number Candidate number Surname Forename(s) Candidate signature I declare this is my own work. GCSE COMBINED SCIENCE: TRILOGY Foundation Tier Chemistry Paper 2F F 2 *02* IB/M/Jun22/8464/C/2F 0 1 This question is about the Earth’s atmosphere. 0 1 . 1 The Earth’s atmosphere contains 21% oxygen. Draw the bar for oxygen on Figure 1. [1 mark] Figure 1 0 1 . 2 What is used to test for oxygen gas? [1 mark] Tick () one box. A burning splint A glowing splint Damp litmus paper Limewater Do not write outside the box 3 *03* Turn over ► IB/M/Jun22/8464/C/2F Do not write outside the The Earth’s early atmosphere was very different from the Earth’s atmosphere today. box Figure 2 shows the composition of the Earth’s early atmosphere and of the Earth’s atmosphere today. Figure 2 0 1 . 3 The percentages of nitrogen and oxygen in the Earth’s atmosphere today are different from the Earth’s early atmosphere. Complete the sentences. Choose answers from the box. Use Figure 2. Each answer can be used once, more than once or not at all. [2 marks] decreased increased stayed the same Since the Earth’s early atmosphere, the percentage of nitrogen in the Earth’s atmosphere has . Since the Earth’s early atmosphere, the percentage of oxygen in the Earth’s atmosphere has . 4 *04* IB/M/Jun22/8464/C/2F Do not write outside the 0 1 box . 4 The Earth’s atmosphere today contains a small amount of carbon dioxide. Why has the percentage of carbon dioxide decreased since the Earth’s early atmosphere? [2 marks] Tick () two boxes. Dissolved in oceans Formation of sedimentary rocks Industrialisation Respiration Volcanic activity 5 *05* Turn over ► IB/M/Jun22/8464/C/2F Do not write outside the box 9 Oxides of nitrogen are produced when nitrogen reacts with oxygen in car engines. Figure 3 shows the concentration of oxides of nitrogen in the atmosphere during one day in a city. Figure 3 0 1 . 5 Which two times have the highest concentrations of oxides of nitrogen in the atmosphere? [2 marks] 1 2 0 1 . 6 Suggest why there are the highest concentrations of oxides of nitrogen at these times. [1 mark] 6 *06* IB/M/Jun22/8464/C/2F Do not write outside the box 0 2 This question is about fuels. Coal deposits were formed from the remains of trees. 0 2 . 1 Name the process in the leaves of trees that uses carbon dioxide. [1 mark] 0 2 . 2 How is coal formed after trees die? [1 mark] Tick () one box. The trees are burned. The trees are compressed. The trees are melted. Coal contains small amounts of sulfur. 0 2 . 3 Name the gas produced when sulfur burns in oxygen. [1 mark] 0 2 . 4 Give two problems caused by the gas produced when sulfur burns in oxygen. [2 marks] 1 2 7 *07* Turn over ► IB/M/Jun22/8464/C/2F Do not write outside the box 8 0 2 . 5 Figure 4 shows the relative amount of electricity generated from different fuel sources in the UK from 2012 to 2018. Figure 4 Describe what happens to the amounts of fuels used to generate electricity in the UK from 2012 to 2018. [3 marks] Turn over for the next question 8 *08* IB/M/Jun22/8464/C/2F Do not write outside the box 0 3 This question is about ammonia and its compounds. A student heated a sample of ammonium chloride. The equation for the reaction is: NH4Cl ⇌ NH3 + HCl ammonium chloride ammonia 0 3 . 1 One product is ammonia. What is the name of the product with the formula HCl? [1 mark] 0 3 . 2 Ammonia is a gas. What is the state symbol for ammonia? [1 mark] Tick () one box. (aq) (g) (I) (s) 0 3 . 3 How does the equation show that the reaction is reversible? [1 mark] 0 3 . 4 Complete the sentence. [1 mark] The forward reaction is endothermic, so the reverse reaction is . 9 *09* Turn over ► IB/M/Jun22/8464/C/2F Do not write outside the box 0 3 . 5 Complete the sentence. Choose the answer from the box. [1 mark] concentration rate temperature Equilibrium is reached when the forward and reverse reactions happen at exactly the same . Question 3 continues on the next page 10 *10* IB/M/Jun22/8464/C/2F Do not write outside the The industrial process to produce ammonia uses a catalyst. box 0 3 . 6 Figure 5 shows the reaction profile for the reaction with and without a catalyst. Figure 5 Which letter represents the activation energy for the reaction with a catalyst? [1 mark] Tick () one box. A B C D 11 *11* Turn over ► IB/M/Jun22/8464/C/2F Do not write outside the box 8 0 3 . 7 Give one reason why using a catalyst reduces costs. Do not answer in terms of activation energy. [1 mark] 0 3 . 8 Ammonia is in a mixture that is used as a household cleaner. What is a mixture that has been designed as a useful product called? [1 mark] Turn over for the next question 12 *12* IB/M/Jun22/8464/C/2F Do not write outside the box 0 4 A student investigates the effect of concentration on the rate of the reaction between sodium thiosulfate solution and hydrochloric acid. Figure 6 shows the experiment. The experiment was done in a fume cupboard. Figure 6 This is the method used. 1. Pour 50 cm3 of sodium thiosulfate solution into a conical flask. 2. Put the conical flask on a black cross drawn on a piece of paper. 3. Pour 10 cm3 of hydrochloric acid into the conical flask and start a timer. 4. Stop the timer when the cross can no longer be seen. 5. Repeat the experiment with different concentrations of sodium thiosulfate solution. 13 *13* Turn over ► IB/M/Jun22/8464/C/2F Do not write outside the box 0 4 . 1 Draw one line from each type of variable to the correct example of the variable in this investigation. [2 marks] Type of variable Example of variable Dependent Independent Concentration of sodium thiosulfate solution Temperature of reaction mixture Time taken for the cross to no longer be seen Volume of acid Volume of the flask Question 4 continues on the next page 14 *14* IB/M/Jun22/8464/C/2F Do not write outside the box 0 4 . 2 The experiment is done at room temperature. Figure 7 What is the temperature shown on the thermometer in Figure 7? [1 mark] Temperature = °C Table 1 shows the student’s results. Table 1 Concentration of sodium thiosulfate solution in mol/dm3 Time in seconds 0.1 82 0.2 40 0.3 20 0.4 13 0.5 10 0.6 8 15 *15* Turn over ► IB/M/Jun22/8464/C/2F Do not write outside the box 0 4 . 3 Plot the data from Table 1 on Figure 8. Draw a line of best fit. [3 marks] Figure 8 0 4 . 4 Predict the time taken for the cross to no longer be seen at a concentration of 0.7 mol/dm3 Use your graph in Figure 8. [1 mark] Time = s 0 4 . 5 Complete the sentence. [1 mark] As the concentration of sodium thiosulfate solution increases, the time taken for the cross to no longer be seen . 16 *16* IB/M/Jun22/8464/C/2F Do not write outside the box 0 4 . 6 In one experiment 0.725 g of sulfur is produced in 20 seconds. Calculate the mean rate of the reaction from 0 to 20 seconds. Use the equation: mean rate of reaction = mass of sulfur produced in grams time in seconds [2 marks] Mean rate of reaction = 0 4 . 7 What is the unit for the mean rate of reaction calculated in Question 04.6? [1 mark] Tick () one box. g g/s s s/g 17 *17* Turn over ► IB/M/Jun22/8464/C/2F Do not write outside the box 14 0 4 . 8 The student did the experiment with 0.15 mol/dm3 sodium thiosulfate solution and repeated the experiment three more times. Table 2 shows the results. Table 2 Test 1 Test 2 Test 3 Test 4 Time in seconds for the cross to no longer be seen 60.5 63.2 82.3 65.7 Calculate the mean time for this reaction. Do not include the anomalous result in your calculation. Give your answer to 3 significant figures. [3 marks] Mean time for the reaction (3 significant figures) = s Turn over for the next question 18 *18* IB/M/Jun22/8464/C/2F Do not write outside the box 0 5 This question is about hydrocarbons. Figure 9 shows a hydrocarbon. Figure 9 0 5 . 1 Complete the formula for the hydrocarbon shown in Figure 9. [1 mark] C H 0 5 . 2 What is the name of the hydrocarbon in Figure 9? [1 mark] 0 5 . 3 Which homologous series does the hydrocarbon in Figure 9 belong to? [1 mark] 19 *19* Turn over ► IB/M/Jun22/8464/C/2F Do not write outside the box 0 5 . 4 30 g of another hydrocarbon contains 24 g of carbon. Which calculation gives the percentage of carbon in the hydrocarbon? [1 mark] Tick () one box. 24 × 30 100 100 × 30 24 24 × 100 30 24 30 × 100 0 5 . 5 Table 3 shows boiling points of some hydrocarbons. Table 3 Formula of hydrocarbon Boiling point in °C C2H6 –89 C4H10 0 C6H14 69 C8H18 125 C10H22 174 Describe how the boiling points change as the number of carbon atoms in the hydrocarbon increases. [1 mark] 20 *20* IB/M/Jun22/8464/C/2F Do not write outside the Hydrocarbons can be cracked. box 0 5 . 6 Give one condition used to crack hydrocarbons. [1 mark] 0 5 . 7 Balance the equation for the cracking of C6H14 [1 mark] C6H14 → C2H6 + C2H4 0 5 . 8 Give one reason why hydrocarbons are cracked. [1 mark] 21 *21* Turn over ► IB/M/Jun22/8464/C/2F Do not write outside the box 11 0 5 . 9 Window frames can be manufactured from wood or plastic. Table 4 shows the results of a life cycle assessment (LCA) for making one wooden and one plastic window frame. Both window frames are the same size. Table 4 Wooden frame Plastic frame Total energy used in MJ Coal and oil used in kg 5 18 Waste produced in kg 16 28 Cost to buy and maintain in £ 147 102 Give three advantages of using wood instead of plastic in the manufacture of window frames. [3 marks] Advantage of wood 1 Advantage of wood 2 Advantage of wood 3 Turn over for the next question 22 *22* IB/M/Jun22/8464/C/2F Do not write outside the box 0 6 A student investigated the colours in a brown ink using chromatography. 0 6 . 1 Figure 10 shows the apparatus used. Figure 10 Give two errors made by the student. Describe the problem each error would cause. [4 marks] Error 1 Problem 1 Error 2 Problem 2 23 *23* Turn over ► IB/M/Jun22/8464/C/2F Do not write outside the A different student set up the apparatus correctly. box Figure 11 shows the results. Figure 11 0 6 . 2 Give two conclusions the student can make