OxfordAQA International Specification 9620

OxfordAQA International AS & A-Level Chemistry Revision Hub

Modular specification guide, topic study notes, Paper 5 required practical walkthroughs, and longitudinal grade boundary analysis for international students.

Modular Structure & Unit Navigation

The OxfordAQA 9620 qualification is divided into five modular units. Candidates can take AS units (CH01 and CH02) for an AS award (9621) or complete all five units for the full International A-Level award (9622).

Unit 1: CH01 50% AS | 20% A-Level

Inorganic 1 & Physical 1

Foundation physical principles and fundamental inorganic periodicity trends.

70 Marks 1 hour 30 mins 100 UMS
  • Stoichiometry (Vertical Quantitative Backbone)
  • Atomic Structure & TOF Mass Spectrometry
  • Amount of Substance & Solution Titrations
  • Chemical Bonding & VSEPR Molecular Shapes
  • Periodicity & Trends Across Period 3
  • Group 2: The Alkaline Earth Metals
  • Group 7: Halogens & Halide Redox Behavior
Unit 2: CH02 50% AS | 20% A-Level

Organic 1 & Physical 1

Core organic reaction mechanisms, physical kinetics, energetics, and equilibria.

70 Marks 1 hour 30 mins 100 UMS
  • Energetics, Calorimetry & Hess Law Cycles
  • Kinetics, Collision Theory & Catalysis
  • Equilibria & Equilibrium Constant Kc
  • Alkanes & Free-Radical Substitution
  • Halogenoalkanes & Nucleophilic Mechanisms
  • Alkenes & Electrophilic Addition
  • Alcohols & Industrial Synthesis Routes
  • Organic Analysis (Infrared & Mass Spectrometry)
Unit 3: CH03 21% A-Level (A2)

Inorganic 2 & Physical 2

Advanced thermodynamics, rate equations, electrochemical cells, and transition metals.

80 Marks 1 hour 30 mins 105 UMS
  • Thermodynamics, Born-Haber Cycles & Entropy
  • Rate Equations & Arrhenius Graphical Analysis
  • Equilibrium Constant Kp in Gas Systems
  • Electrode Potentials & Electrochemical Cells
  • Acids, Bases, Buffer Systems & pH Curves
  • Period 3 Elements and Their Oxides
  • Transition Metals & Complex Ion Formation
  • Reactions of Metal Ions in Aqueous Solution
Unit 4: CH04 21% A-Level (A2)

Organic 2 & Physical 2

Stereochemistry, aromatic substitution, carbonyls, polymers, and advanced spectroscopy.

80 Marks 1 hour 30 mins 105 UMS
  • Optical Isomerism & Chiral Enantiomers
  • Aldehydes, Ketones & Nucleophilic Addition
  • Carboxylic Acids, Esters & Acyl Chlorides
  • Aromatic Chemistry & Benzene Nitration
  • Amines, Basic Strength & Synthesis
  • Polymers (Polyesters, Polyamides & Nylon)
  • Amino Acids, Proteins, DNA & Cisplatin
  • Organic Synthesis Strategy & NMR Spectroscopy
Unit 5: CH05 18% A-Level (A2 Capstone)

Practical & Synoptic Capstone

Written assessment of practical skills, experimental design, uncertainty math, and synoptic links.

60 Marks 1 hour 25 mins 90 UMS
  • Experimental Design & Systematic Variable Control
  • Quickfit Apparatus Assembly (Reflux & Distillation)
  • Data Evaluation, Significant Figures & Graphing
  • Exact Percentage Uncertainty for Glassware & Balances
  • Synoptic Integration Across Units CH01 to CH04
  • Highest A* Volatility Component (~86.7% Raw Needed)
Practicals: RP1 to RP10 Paper 5 Core

The 10 Required Practicals

Step-by-step laboratory procedures, Quickfit setups, hazard safety, and error formulas.

10 Standard Labs Illustrated Setups Safety Protocols
  • RP1: Volumetric Solution & Acid-Base Titration
  • RP2: Enthalpy Change Measurement & Cooling Curves
  • RP3: Rate of Reaction with Temperature
  • RP4: Qualitative Analysis (Cations & Anions)
  • RP5: Reaction Rates (Continuous Gas Monitoring)
  • RP6: Organic Distillation & Functional Group Tests
  • RP7: pH Titration Curves & Ka Determination
  • RP8: Electrochemical Cells & EMF Measurement
  • RP9: Transition Metal Ions & Ligand Exchange
  • RP10: Synthesis and Purification of Organic Solid/Liquid

Assessment Windows & Certification Advice

How the OxfordAQA modular system works: assessment sessions, resit regulations, UMS conversion, and the specific criteria required to achieve an A* grade.

Bi-Annual Exam Windows

OxfordAQA examinations run in two discrete assessment windows each academic year:

  • January Series: Units CH01, CH02, CH03, and CH04 are available for assessment.
  • May/June Series: All five units (CH01, CH02, CH03, CH04, and CH05) are available.
  • Paper 5 Note: Unit CH05 is assessed exclusively in the May/June examination window.

Resit & Cash-in Freedom

The modular framework provides extensive flexibility for candidate score optimization:

  • Unlimited Resits: Candidates may retake any unit. The highest raw mark and UMS achieved on each unit is banked automatically.
  • AS Cash-in (9621): Candidates may combine CH01 and CH02 to receive a standalone AS certificate.
  • A-Level Cash-in (9622): Aggregates the best marks across all five units for the final A-Level award.

The A* Qualification Rule

Achieving an overall A* requires meeting two strict mathematical thresholds:

  • Criterion 1: An overall Grade A award across the entire qualification (at least 400 out of 500 total UMS, or 80%).
  • Criterion 2: An aggregate of at least 90% across the three A2 units combined (at least 270 out of 300 UMS across CH03, CH04, and CH05).
  • Individual Units: A* is not awarded on individual unit certificates; it is awarded solely on the final subject award.
Historical Reference Data

Longitudinal Grade Boundary Module

Official raw mark and UMS boundaries from June 2024, June 2023, January 2023, and June 2022. Use these official benchmarks to plan your target marks accurately.

June 2024 Official Raw Mark Boundaries

Unit Code Unit Title Max Mark A* Mark (%) A Mark (%) B Mark (%) C Mark (%) D Mark (%) E Mark (%)
CH01 Inorganic 1 & Physical 1 70 - 54 (77.1%) 48 (68.6%) 42 (60.0%) 36 (51.4%) 30 (42.9%)
CH02 Organic 1 & Physical 1 70 - 52 (74.3%) 45 (64.3%) 38 (54.3%) 31 (44.3%) 25 (35.7%)
CH03 Inorganic 2 & Physical 2 80 68 (85.0%) 60 (75.0%) 52 (65.0%) 44 (55.0%) 36 (45.0%) 29 (36.3%)
CH04 Organic 2 & Physical 2 80 70 (87.5%) 62 (77.5%) 54 (67.5%) 46 (57.5%) 38 (47.5%) 31 (38.8%)
CH05 Practical & Synoptic Capstone 60 52 (86.7%) 46 (76.7%) 40 (66.7%) 34 (56.7%) 29 (48.3%) 24 (40.0%)

* Note: A dash (-) indicates that an A* grade is not awarded at the unit level for AS units CH01 and CH02.

June 2023 Official Raw Mark Boundaries

Unit Code Unit Title Max Mark A* Mark (%) A Mark (%) B Mark (%) C Mark (%) D Mark (%) E Mark (%)
CH01 Inorganic 1 & Physical 1 70 - 54 (77.1%) 47 (67.1%) 41 (58.6%) 35 (50.0%) 29 (41.4%)
CH02 Organic 1 & Physical 1 70 - 52 (74.3%) 44 (62.9%) 36 (51.4%) 28 (40.0%) 21 (30.0%)
CH03 Inorganic 2 & Physical 2 80 68 (85.0%) 60 (75.0%) 52 (65.0%) 44 (55.0%) 36 (45.0%) 29 (36.3%)
CH04 Organic 2 & Physical 2 80 71 (88.8%) 63 (78.8%) 55 (68.8%) 47 (58.8%) 39 (48.8%) 31 (38.8%)
CH05 Practical & Synoptic Capstone 60 52 (86.7%) 46 (76.7%) 40 (66.7%) 34 (56.7%) 29 (48.3%) 24 (40.0%)

* Note: A dash (-) indicates that an A* grade is not awarded at the unit level for AS units CH01 and CH02.

January 2023 Official Raw Mark Boundaries

Unit Code Unit Title Max Mark A* Mark (%) A Mark (%) B Mark (%) C Mark (%) D Mark (%) E Mark (%)
CH01 Inorganic 1 & Physical 1 70 - 52 (74.3%) 45 (64.3%) 38 (54.3%) 32 (45.7%) 26 (37.1%)
CH02 Organic 1 & Physical 1 70 - 52 (74.3%) 45 (64.3%) 38 (54.3%) 32 (45.7%) 26 (37.1%)
CH03 Inorganic 2 & Physical 2 80 64 (80.0%) 56 (70.0%) 48 (60.0%) 40 (50.0%) 33 (41.3%) 26 (32.5%)
CH04 Organic 2 & Physical 2 80 63 (78.8%) 55 (68.8%) 47 (58.8%) 39 (48.8%) 31 (38.8%) 24 (30.0%)
CH05 Practical & Synoptic Capstone 60 48 (80.0%) 43 (71.7%) 38 (63.3%) 33 (55.0%) 28 (46.7%) 23 (38.3%)

* Note: A dash (-) indicates that an A* grade is not awarded at the unit level for AS units CH01 and CH02.

June 2022 Official Raw Mark Boundaries

Unit Code Unit Title Max Mark A* Mark (%) A Mark (%) B Mark (%) C Mark (%) D Mark (%) E Mark (%)
CH01 Inorganic 1 & Physical 1 70 - 52 (74.3%) 45 (64.3%) 38 (54.3%) 32 (45.7%) 26 (37.1%)
CH02 Organic 1 & Physical 1 70 - 52 (74.3%) 45 (64.3%) 38 (54.3%) 32 (45.7%) 26 (37.1%)
CH03 Inorganic 2 & Physical 2 80 64 (80.0%) 56 (70.0%) 48 (60.0%) 40 (50.0%) 33 (41.3%) 26 (32.5%)
CH04 Organic 2 & Physical 2 80 63 (78.8%) 55 (68.8%) 47 (58.8%) 39 (48.8%) 31 (38.8%) 23 (28.8%)
CH05 Practical & Synoptic Capstone 60 49 (81.7%) 43 (71.7%) 37 (61.7%) 32 (53.3%) 27 (45.0%) 22 (36.7%)

* Note: A dash (-) indicates that an A* grade is not awarded at the unit level for AS units CH01 and CH02.

Uniform Mark Scale (UMS) Conversion Framework

Raw marks are converted into UMS to account for differences in paper difficulty across examination series.

Component / Award Max UMS A* UMS A UMS (80%) B UMS (70%) C UMS (60%) D UMS (50%) E UMS (40%)
Unit 1 (CH01) 100 - 80 70 60 50 40
Unit 2 (CH02) 100 - 80 70 60 50 40
Unit 3 (CH03) 105 - 84 74 63 53 42
Unit 4 (CH04) 105 - 84 74 63 53 42
Unit 5 (CH05) 90 - 72 63 54 45 36
International AS (9621) 200 - 160 140 120 100 80
International A-Level (9622) 500 400 + 270 A2 400 350 300 250 200

To qualify for A*, candidates must achieve an overall total of at least 400 UMS (Grade A) plus an aggregate of at least 270 UMS out of 300 across the three A2 units: CH03 (105 UMS) + CH04 (105 UMS) + CH05 (90 UMS).

Strategic Alert: CH05 High A* Volatility

Historical grade boundaries reveal that Unit 5 (CH05) is the single most sensitive component for A* attainment. Because CH05 carries a maximum total of only 60 marks, every single lost mark reduces your raw percentage by 1.67%. In June 2024 and June 2023, the A* threshold was set at 52 marks (86.7%).

Candidates dropping just 9 marks fall below the component A* standard. To maintain the mandatory 90% A2 aggregate threshold, any mark deficiency on CH05 forces a student to score upwards of 92% to 94% on CH03 and CH04. Complete mastery of Paper 5 required practicals and percentage error mathematics is the decisive factor for an A*.

CH05 Max Marks 60
Mark Sensitivity 1.67% / mark
June 2024 A* Boundary 52 / 60 (86.7%)
Allowable Mark Loss for A* 8 Marks Only

Interactive Candidate Benchmark Estimator

Enter your target or trial raw marks across each unit to calculate your projected UMS, determine your overall grade, and verify your eligibility for the A* dual criteria hurdle (Total UMS >= 400 and A2 UMS >= 270).

303 / 360
Total Raw Score (84.2%)
435 / 500 UMS
Total UMS (87.0%)
270 / 300 UMS
A2 UMS (90.0%)
Grade A*
Qualifies for A* (Total UMS >= 400 and A2 UMS >= 270 hurdle cleared)

High-Yield Examiner Differentiators

Direct insights from OxfordAQA examiner reports to secure maximum marks in modular papers.

Curly Arrow Precision

Curly arrows indicate the precise movement of a pair of electrons. In organic mechanisms:

  • Origin: Must start strictly from a lone pair of electrons or the center of a covalent bond.
  • Destination: Must point directly to the specific atom forming the new bond.
  • Zero Tolerance: Arrows starting from charge signs or floating in empty space lose marks immediately.

Zero Intermediate Rounding

Vertical quantitative chemistry links Units CH01, CH03, and CH05:

  • Full Registers: Store intermediate numbers in calculator memory across all titration, gas law, and enthalpy steps.
  • Premature Rounding: Rounding midway causes compounded errors that forfeit the final accuracy mark.
  • Significant Figures: Match final answers to the least precise piece of experimental data given.

Quickfit Joint Setup

Paper 5 demands technical understanding of laboratory apparatus:

  • Reflux Condenser: Must remain open at the top. Sealing the top creates a closed vessel that can fracture under pressure.
  • Water Direction: Water must enter the condenser jacket at the bottom and exit at the top to prevent air pockets.
  • Thermometer Bulb: In distillation, the bulb must align precisely with the condenser side-arm entrance.