AQA A-Level Chemistry Paper 3, June 2025
Every question from AQA A-Level Chemistry Paper 3, June 2025 (7405): 36 questions, 90 marks, each with its mark scheme and topic.
- Question 1 9 marks
Determine the enthalpy of solution of potassium hydroxide experimentally and theoretically using calorimetry calculations and Born–Haber cycle data.
Physical Chemistry · Required Practicals · 3.1.4 Energetics · 3.1.8 Thermodynamics · Required Practical 2: Measurement of an enthalpy change
- Question 2 15 marks
Investigate the rate of reaction between hydrogen peroxide, iodide ions, and acid using an iodine clock method to determine orders of reaction, rate equation, initial rate, and evaluate experimental uncertainties.
Physical Chemistry · Required Practicals · 3.1.9 Rate Equations · 3.1.2 Amount of Substance · Required Practical 7: Measuring the rate of reaction by an initial rate method
- Question 3 11 marks
Identify apparatus errors in a standard electrode potential setup, state the voltmeter property required to measure cell EMF, deduce overall cell reactions, and use electrode potential data to explain redox observations and calculate cell EMF.
Physical Chemistry · Required Practicals · 3.1.11 Electrode Potentials · Required Practical 8: Measuring the EMF of an electrochemical cell
- Question 4 9 marks
Write the Kc expression, explain why a sample is quenched with ice-cold water before titration, and calculate the value and units of Kc for an equilibrium between iron(III) and iodide ions.
Physical Chemistry · 3.1.6 Chemical Equilibria, Le Chatelier's Principle and Kc · 3.1.2 Amount of Substance · 3.1.5 Kinetics
- Question 5 10 marks
Describe a method to distinguish propan-1-ol and propan-2-ol using oxidation, chemical tests, and infrared spectroscopy, state the purpose of anti-bumping granules, and draw labelled apparatus for heating under reflux.
Organic Chemistry · Required Practicals · 3.3.5 Alcohols · 3.3.6 Organic Analysis · 3.3.8 Aldehydes and Ketones · Required Practical 5: Distillation of a product from a reaction · Required Practical 6: Tests for alcohol, aldehyde, alkene and carboxylic acid
- Question 6 6 marks
Identify stereoisomerism in a triglyceride from rapeseed oil, determine double bond locants and stereoisomer counts for methyl esters, and state products and uses of saponification and transesterification.
Organic Chemistry · 3.3.1 Introduction to Organic Chemistry · 3.3.9 Carboxylic Acids and Derivatives
- Question 7 1 mark
Identify the formula for the quaternary ammonium cation produced in the reaction between methylamine and excess bromoethane.
Organic Chemistry · 3.3.11 Amines · 3.3.3 Halogenoalkanes
- Question 8 1 mark
Identify which reaction involving potassium hydroxide (KOH) does not involve it acting as a base.
Organic Chemistry · 3.3.3 Halogenoalkanes · 3.3.9 Carboxylic Acids and Derivatives · 3.3.11 Amines
- Question 9 1 mark
Identify which statement correctly describes the effect of using a catalyst in a reversible reaction.
Physical Chemistry · 3.1.5 Kinetics · 3.1.6 Chemical Equilibria, Le Chatelier's Principle and Kc
- Question 10 1 mark
Identify which diagram correctly shows the curly arrows in the mechanism for the elimination reaction of bromoethane.
Organic Chemistry · 3.3.3 Halogenoalkanes · 3.3.1 Introduction to Organic Chemistry
- Question 11 1 mark
Identify the correct classification of Period 3 oxides into giant ionic, giant covalent, and simple molecular structures.
Inorganic Chemistry · Physical Chemistry · 3.2.4 Properties of Period 3 Elements and Their Oxides · 3.1.3 Bonding
- Question 12 1 mark
Calculate the percentage abundance of 235UF6 in a sample given the relative molecular mass of the sample and the isotopes present.
Physical Chemistry · 3.1.1 Atomic Structure · 3.1.2 Amount of Substance
- Question 13 1 mark
Identify which compound reacts with concentrated sulfuric acid to form an intermediate that reacts with excess water to produce an alcohol.
Organic Chemistry · 3.3.4 Alkenes · 3.3.5 Alcohols
- Question 14 1 mark
Identify the correct and complete observation when a piece of strontium is added to an excess of water.
Inorganic Chemistry · 3.2.2 Group 2, The Alkaline Earth Metals
- Question 15 1 mark
Identify the correct statement regarding trends in physical properties across Period 3.
Inorganic Chemistry · 3.2.1 Periodicity
- Question 16 1 mark
Identify the incorrect statement regarding the first ionisation energies of Period 3 elements.
Inorganic Chemistry · Physical Chemistry · 3.2.1 Periodicity · 3.1.1 Atomic Structure
- Question 17 1 mark
Identify the type(s) of stereoisomerism shown by the complex ion [Cr(H2NCH2CH2NH2)3]3+.
Inorganic Chemistry · 3.2.5 Transition Metals
- Question 18 1 mark
Identify the correct structural formula for 4-chloro-2-methylpent-2-enoic acid from four multiple choice options.
Organic Chemistry · 3.3.1 Introduction to Organic Chemistry · 3.3.9 Carboxylic Acids and Derivatives
- Question 19 1 mark
Identify which Period 3 oxide produces a solution with the lowest pH when added to water.
Inorganic Chemistry · 3.2.4 Properties of Period 3 Elements and Their Oxides
- Question 20 1 mark
Identify which property of the Group 2 elements increases with increasing atomic number.
Inorganic Chemistry · 3.2.2 Group 2, The Alkaline Earth Metals
- Question 21 1 mark
Identify which electron configuration corresponds to an element with a maximum oxidation state of +5 in its compounds.
Physical Chemistry · Inorganic Chemistry · 3.1.1 Atomic Structure · 3.2.5 Transition Metals · 3.1.7 Oxidation, Reduction and Redox Equations
- Question 22 1 mark
Identify the correct statement regarding the composition and geometry of the complex ion present in Tollens' reagent.
Inorganic Chemistry · Organic Chemistry · 3.2.5 Transition Metals · 3.3.8 Aldehydes and Ketones
- Question 23 1 mark
Identify which reaction produces an octahedral complex ion from the given options.
Inorganic Chemistry · 3.2.5 Transition Metals · 3.2.6 Reactions of Ions in Aqueous Solution
- Question 24 1 mark
Identify the correct statement regarding the production of ethanol biofuel by fermentation.
Organic Chemistry · 3.3.5 Alcohols
- Question 25 1 mark
Identify which of the given elements is in the p block of the Periodic Table.
Inorganic Chemistry · Physical Chemistry · 3.2.1 Periodicity · 3.1.1 Atomic Structure
- Question 26 1 mark
Identify which statement about the stoichiometry of reactions involving Period 3 oxides is correct.
Inorganic Chemistry · Physical Chemistry · 3.2.4 Properties of Period 3 Elements and Their Oxides · 3.1.2 Amount of Substance
- Question 27 1 mark
Identify which species from a given list has a tetrahedral shape.
Physical Chemistry · Inorganic Chemistry · 3.1.3 Bonding · 3.2.5 Transition Metals
- Question 28 1 mark
Identify the correct statement about the fractional distillation and cracking of alkanes.
Organic Chemistry · 3.3.2 Alkanes
- Question 29 1 mark
Identify the structure of the dipeptide formed from serine and alanine.
Organic Chemistry · 3.3.13 Amino Acids, Proteins and DNA
- Question 30 1 mark
Identify the correct order of decreasing pH for solutions formed when equal amounts of sodium, magnesium, and chlorine are added separately to water.
Inorganic Chemistry · 3.2.4 Properties of Period 3 Elements and Their Oxides · 3.2.3 Group 7(17), The Halogens
- Question 31 1 mark
Identify the shapes around the central atom in the acid molecules formed when phosphorus(V) oxide and sulfur dioxide react with water.
Physical Chemistry · Inorganic Chemistry · 3.1.3 Bonding · 3.2.4 Properties of Period 3 Elements and Their Oxides
- Question 32 1 mark
Identify the correct structure of transplatin from given square planar and tetrahedral representations.
Inorganic Chemistry · Organic Chemistry · 3.2.5 Transition Metals · 3.3.13 Amino Acids, Proteins and DNA
- Question 33 1 mark
Identify which two labelled R group interactions in a protein's tertiary structure represent an intermolecular force and a covalent bond, respectively.
Organic Chemistry · Physical Chemistry · 3.3.13 Amino Acids, Proteins and DNA · 3.1.3 Bonding
- Question 34 1 mark
Identify the correct statement about enzymes from the given options.
Organic Chemistry · 3.3.13 Amino Acids, Proteins and DNA
- Question 35 1 mark
Identify which compound can be used as a cationic surfactant from four given organic formulas.
Organic Chemistry · 3.3.11 Amines
- Question 36 1 mark
Identify which ion is formed during the mechanism for the acid-catalysed hydration of 1-methylcyclopent-1-ene to produce the major product.
Organic Chemistry · 3.3.1 Introduction to Organic Chemistry · 3.3.4 Alkenes · 3.3.5 Alcohols