Advanced quantitative physical principles and transition element inorganic chemistry for OxfordAQA International A-Level Chemistry (Specification 9620). Complete unit study notes, examiner differentiators, and assessment guidance.
Unit 3 (CH03) represents the first A2 modular assessment in the OxfordAQA International A-Level qualification. Building directly on the foundational principles established in AS Unit 1 (CH01) and Unit 2 (CH02), Unit 3 explores the energetic drivers of chemical reactions, quantitative kinetics, gaseous equilibrium expressions, electrochemical potentials, solution acid-base chemistry, and transition metal coordination complexes.
Unit CH03 is examined in both the January series and the May/June series. Candidates typically sit CH03 in January of Year 13 as a modular milestone, allowing a resit opportunity in May/June to bank their highest UMS mark before final qualification cash-in (code 9622).
To achieve the final award of Grade A*, candidates must secure an overall Grade A across all 5 units (>= 400/500 total UMS) AND score at least 90% aggregate across the three A2 units (CH03, CH04, and CH05). A commanding performance in CH03 provides essential headroom for the A* threshold.
Select a syllabus node below to access comprehensive revision notes, illustrated mechanisms, worked mathematical solutions, and exam-style practice questions:
Born-Haber energy cycles, lattice enthalpy of formation and dissociation, hydration and solution enthalpies, entropy (delta S), Gibbs free energy feasibility (delta G = delta H - T delta S), and feasibility temperature calculations.
Open Topic Notes →Rate expressions (rate = k[A]^m[B]^n), reaction orders, initial rate methods, rate-determining steps in multi-step mechanisms, and Arrhenius plots of ln k against 1/T to deduce activation energy.
Open Topic Notes →Gas phase equilibrium-kp calculations, mole fractions, partial pressures, Kp expressions and unit deductions, ICE table calculations, and the response of Kp to temperature, pressure, and catalysts.
Open Topic Notes →Standard hydrogen electrode (SHE), IUPAC conventional cell notation, cell EMF calculations, thermodynamic redox feasibility, commercial lithium-ion batteries, and hydrogen-oxygen fuel cells.
Open Topic Notes →Complete acids-and-bases framework: Bronsted-Lowry pairs, Kw and water neutrality at elevated temperatures, weak acid Ka calculations, buffer solution action via Henderson-Hasselbalch, and pH titration curves with indicator selection.
Open Topic Notes →Structures and bonding of Period 3 oxides from Na2O to SO3, reactions with water and pH trends, and basic, acidic, and amphoteric reactions of aluminum oxide with hydrochloric acid and sodium hydroxide.
Open Topic Notes →D-block electronic configurations, variable oxidation states, ligand coordinate bonding, chelate effect entropy, complex geometries, d-orbital splitting and color origin (delta E = h nu), and catalytic mechanisms.
Open Topic Notes →Comprehensive reactions-of-aqueous-ions: acidity differences between hexaaqua 2+ and 3+ ions, precipitation reactions with sodium hydroxide and ammonia, amphoteric dissolution of Al(OH)3 in excess alkali, and reactions with sodium carbonate.
Open Topic Notes →Complete 80-mark authentic mock examination paper: 15 Section A interactive multiple choice questions and 6 Section B structured questions with full mark schemes and examiner guidance.
Open Unit 3 Mock Exam →