AQA GCSE Separate Science Chemistry – Paper 1 Higher Tier Predicted Paper 2023 With marking scheme

AQA GCSE Separate Science Chemistry – Paper 1 Higher Tier Predicted Paper 2023 With marking scheme Name …………………………………………………………………… Date ………………… 1 hour 45 minutes allowed. You may use a calculator and an AQA periodic table. Grade boundaries These are VERY rough guesses! Getting a 7 on this paper does not guarantee you the same mark in the exam. • 9 70% • 8 60% • 7 50% • 6 45% • 5 35% • 4 30% • 3 25% 01 Atoms are made up from subatomic particles; electrons, neutrons and protons. a) Describe the structure of the atom, stating the location of each of the subatomic particles. [3 marks] b) The model of the atom has changed over time as new experimental evidence arises. State the order in which the subatomic particles were discovered. [2 marks] c) State who suggested the location of electrons. [1 mark] d) State who discovered neutrons. [1 mark] e) Rutherford wanted to study the plum pudding model of the atom, by running an alpha scattering experiment. Describe what Rutherford found and explain how this changed the model of the atom. [4 marks] 02 Ammonia, NH3, is a small molecule that is a liquid at -35C and a gas at -30C. a) State the bonding seen in ammonia. [1 mark] b) Draw the bonding in ammonia using a dot and cross diagram. [3 marks] c) Compare the behaviour of the particles in ammonia liquid and ammonia gas. [4 marks] d) When ammonia boils, bonds are broken, and it turns from a liquid to a gas. Describe which bonds are broken and why and which ones are not broken and why. [4 marks] 03 Iron oxide is used as a catalyst in the Haber process. a) Transition metals can be used as catalysts. State the property that leads to this behaviour. [1 mark] b) Iron oxide can have the formulae Fe2O3 or Fe3O2. Determine which has the greater molecular mass. [3 marks] c) Explain how you could visually determine the difference between solutions of iron (ii) oxide and iron (iii) oxide. [2 marks] d) Both iron and lithium can form compounds with oxygen to form oxides. State the type of bonding that is seen in both iron and lithium oxide. [1 mark] e) Draw the bonding that is seen in lithium oxide using a dot and cross diagram. [3 marks] f) Compare how iron and lithium react with oxygen. [2 marks] 04 Sulphuric acid is a common solution that is used in the manufacture of fertilisers and salts. a) Suggest a pH for sulfuric acid. [1 mark] b) Describe the general reaction between the ions produced from an aqueous acid and the ions produced from an aqueous alkali. You should include an equation in your answer. [3 marks] c) Zinc metal reacts with sulphuric acid (H2SO4) to give two products. Write the balanced chemical equation for this reaction. [2 marks] d) 2 mol/dm3 sulfuric acid is a strong, concentrated acid. Explain what scientists mean when they use the terms ‘strong’ and ‘concentrated’ in terms of an acid. [2 marks] e) A student wanted to look at the reaction between a strip of zinc metal and sulfuric acid. They set up the equipment as shown in the image below Method 1. Place a conical flask on a mass balance. 2. Measure out 20cm3 of sulfuric acid and add it to the conical flask. 3. Measure 2cm strip of zinc ribbon. 4. Add ribbon to conical flask. 5. Record the initial mass. 6. Record the mass every 30 seconds. 7. Repeat to get 3 sets of results. The student recorded this data in the table below: Time (seconds) Change in mass(g) Test 1 Test 2 Test 3 Mean 0 0 0 0 0 30 15 19 20 18 60 25 27 29 27 90 29 45 31 120 33 34 35 34 i. Calculate the mean value for change in mass at 90 seconds [2 marks] ii. Describe and explain how the mass changed. [2 marks] iii. Give one way in which the student ensures this was a fair test, and how they measured it. [2 marks] iv. The table shows loss of mass, explain why this is not what the student measured. [2 marks] v. Sketch a graph for mean loss of mass vs. time [3 marks] 05 Hydrogen-oxygen fuel cells are suggested as an alternative to rechargeable batteries. a) The overall reaction the occurring within a hydrogen oxygen fuel cells is shown below Hydrogen + Oxygen  Water H2(g) + O2(g)  2H2O(l) Give the states of each substance in the equation. [2 marks] b) Give the half equations that happen at each electrode. i. Negative electrode… [3 marks] ii. Positive electrode…. [3 marks] c) Use the information given in the question and your prior knowledge to evaluate the use of hydrogen-oxygen fuels cells. [6 marks]