A-Level Chemistry Revision: Where the Marks Are in 2026
Recall is capped at about three marks in ten. This page is about the other seven.
Book a Free ConsultationRecall is capped at about three marks in ten. This page is about the other seven.
Book a Free ConsultationA-level Chemistry revision is the allocation of study time across three assessment objectives that Ofqual fixes for every exam board: AO1 recall at 30 to 35 per cent of the marks, AO2 application at 40 to 45 per cent, and AO3 analysis and evaluation at 25 to 30 per cent. On AQA's specification that is roughly 90 of 300 marks for remembering chemistry and 210 for using it.
Checked August 2026. Every assessment objective weighting below was re-read in the exam boards' own current specification documents rather than taken from a summary, and the AQA figures were set against the June 2026 subject and notional component grade boundaries published on results day. No board has changed its assessment objective weightings. This page was rewritten from a version published in June 2026 that carried no mark-level data at all.
Ofqual, not the exam boards, decides how much of an A level science qualification may reward remembering. Its subject-level conditions for biology, chemistry and physics set three assessment objectives and a permitted band for each, and every awarding body has to sit inside them.
| Specification | AO1 — recall | AO2 — application | AO3 — analysis and evaluation |
|---|---|---|---|
| Ofqual permitted band, A level | 30–35% | 40–45% | 25–30% |
| AQA Chemistry 7405 | 30% | 45% | 25% |
| OCR Chemistry A (H432) | 31–34% | 40–44% | 25–28% |
| Pearson Edexcel Chemistry (9CH0) | 31–33% | 41–43% | 25–27% |
| Eduqas Chemistry | 30.7% | 42.7% | 26.7% |
Source: Ofqual, AQA, OCR, Pearson Edexcel and Eduqas specification documents, retrieved 16 August 2026.
Two things follow, and neither is a matter of opinion. The first is that no board rewards recall with more than about a third of its marks, so a student whose revision consists of learning notes is competing for a minority of the paper however thoroughly they do it. The second is that the boards agree with each other far more closely than the revision market implies. AQA's own specification says so in as many words: assessment objectives “are set by Ofqual and are the same across all AS and A-level Chemistry specifications and all exam boards”.
The differences that do matter between boards are structural rather than editorial — how the content is cut into papers, how long each one is, and what the data booklet hands you in the hall. Those are set out separately in our A-level Chemistry subject guide, which compares all five UK specifications. This page takes the assessment objectives themselves and asks what they mean for how a student spends the ninety hours before an exam.
Percentages are hard to revise against. Marks are not. AQA scales all three of its papers by a factor of one, so its raw and scaled totals are the same number: Paper 1 is 105 marks, Paper 2 is 105, Paper 3 is 90, and the qualification is out of 300. Applying the overall weightings to that total gives the following.
| Objective | AQA weighting | Approximate marks in 300 | What it asks for |
|---|---|---|---|
| AO1 | 30% | 90 | State the reagent, the condition, the colour, the definition, the trend |
| AO2 | 45% | 135 | Use it in a context you have not been shown |
| AO3 | 25% | 75 | Judge whether the data support the conclusion, and improve the method |
Source: AQA specification weightings and scaled marks, retrieved 16 August 2026; mark figures derived by applying the weightings to the 300-mark total.
Now set that against a grade. In the June 2026 series AQA's A* boundary for Chemistry was 255 of 300. A candidate who lost nothing at all on AO1 — every reagent, every condition, every colour, every definition — would arrive at 90 marks and would still need 165 of the remaining 210 to reach that boundary. That is just under 79 per cent of every application and analysis mark on the qualification, and it is the number that explains why so much revision plateaus.
The same arithmetic run downwards is more useful to a student sitting at a grade C. Perfect recall alone is worth 90 marks out of 300. It is not close to a pass at the top end and it never was; the marks that separate grades were always somewhere else. The full boundary tables for AQA, OCR, Edexcel and WJEC are in the subject guide, and they tell the same story on every board.
Not sure which objective is costing your marks?
Send us two marked A-level Chemistry past papers and a specialist chemistry tutor will tag every lost mark as AO1, AO2 or AO3 and tell you which one to work on first. Rated 4.8/5 on Trustpilot.
Book a Free Consultation Message us on WhatsAppThe overall weightings hide something that matters more than they do. Every board publishes its assessment objectives per component as well as per qualification, and on all three of the largest specifications the synoptic paper has a different shape from the content papers.
| Component | AO1 | AO2 | AO3 |
|---|---|---|---|
| AQA Paper 1 (of that paper) | 30% | 48% | 22% |
| AQA Paper 2 (of that paper) | 30% | 48% | 22% |
| AQA Paper 3 (of that paper) | 32% | 34% | 34% |
| Edexcel Paper 3 (of the qualification) | 8–10% | 16–18% | 13–15% |
| OCR Unified chemistry H432/03 (of the qualification) | 5–6% | 10–12% | 9–10% |
Source: AQA, Pearson Edexcel and OCR specification documents, retrieved 16 August 2026. AQA publishes component figures as percentages of that paper; Edexcel and OCR publish them as percentages of the whole qualification.
Read the AQA row first. AO3 rises from 22 per cent of Papers 1 and 2 to 34 per cent of Paper 3, and AO2 falls from 48 to 34. In marks that is roughly 31 AO3 marks inside a 90-mark paper, against about 23 inside each 105-mark paper. Edexcel is starker still: its Paper 3 carries 13 to 15 per cent of the whole qualification as AO3 within a paper worth 40 per cent of it, so between 33 and 38 per cent of that paper is analysis and evaluation. OCR's unified component behaves the same way, with AO3 nearly matching AO2 inside it.
This has a direct consequence for a revision timetable. The last paper of the series is the one least improved by another pass through the content, and it is usually the one students revise for by re-reading everything because they have been told it is synoptic. Synoptic does not mean everything at once; on the published figures it means a higher proportion of questions asking you to evaluate rather than recall. Practice for that paper should be built out of data, spectra, unfamiliar reactions and methods to criticise, not out of a second set of notes.
AO2 is the largest block of marks on every specification, and the boards define it precisely enough to revise against. The wording, which is Ofqual's and therefore identical everywhere, is to apply knowledge and understanding “in a theoretical context; in a practical context; when handling qualitative data; when handling quantitative data”. Those are four separable skills, and a student can audit their own revision against each.
The theoretical context is a chemical principle used somewhere it was not taught. Le Chatelier applied to an industrial equilibrium you have never seen; a bond-enthalpy argument transferred to an unfamiliar molecule; electrode potentials used to decide whether a proposed reaction happens at all. The practical context is the chemistry behind an experimental choice: why a reflux condenser rather than distillation, why the acid is added last, why a particular indicator suits that titration.
Handling qualitative data means deduction from observation and spectra — assigning an infrared absorption, reading a proton environment count from a spectrum, identifying an ion from what happened when a reagent was added. Handling quantitative data is where most of the mathematics sits: equilibrium constants, Born-Haber cycles, rate equations, buffer pH, percentage yield and atom economy.
That last point is worth stating plainly, because it changes how the mathematics should be revised. Ofqual requires that mathematical skills in A level Chemistry carry a weighting of at least 20 per cent and, critically, that they “must be tested across the assessment objectives”. AQA repeats the 20 per cent figure in its own specification. Mathematics is therefore not a topic sitting beside the chemistry; it is the vehicle for a large share of AO2 and AO3. Practising calculations in isolation from the chemistry that frames them trains half the skill the paper asks for.
Students often treat AO3 as the part of the paper that cannot be prepared for, on the grounds that you cannot revise thinking. The boards' definition disagrees, and it is unusually specific. AO3 asks you to analyse, interpret and evaluate scientific information, ideas and evidence in order to “make judgements and reach conclusions” and to “develop and refine practical design and procedures”. Those are two distinct, practisable behaviours.
The first is judgement about data. Does this set of results actually support the rate equation proposed? Is a percentage yield of that size consistent with the method described, or does it indicate a systematic error? Which of two mechanisms is consistent with the kinetics? These questions can be rehearsed deliberately, by taking any past-paper data set and writing the conclusion it supports and the conclusion it does not.
The second is method criticism, and it is anchored to practical work by a floor the boards all publish. AQA states that at least 15 per cent of the overall assessment of A-level Chemistry assesses knowledge, skills and understanding in relation to practical work, which is at least 45 of its 300 marks. Eduqas sets the same 15 per cent minimum for what it calls the indirect assessment of practical skills. Those marks are examined in the written papers, so they reward understanding the reasoning behind a procedure rather than having performed it.
A workable revision routine for this is to take each required practical and answer three questions in writing without notes: what is the largest source of uncertainty in this method, what would change in the result if a named step were done wrongly, and what single change would most improve the reliability of the measurement. That is AO3 practice, and it is the part of a revision timetable most often left out. Which practicals each board sets, and how the separately reported endorsement works, is covered in the subject guide rather than repeated here.
Ofqual sets different assessment objective weightings for AS and for A level, and the difference is large enough to change a revision plan. At AS, AO1 is required to be 35 to 40 per cent of the qualification and AO3 only 20 to 25 per cent. At A level, AO1 falls to 30 to 35 per cent and AO3 rises to 25 to 30 per cent.
In other words, the qualification moves away from recall and towards evaluation between the first year and the second. A student who did well in the first year on thorough note-learning is not wrong about how they got there; they are applying a method to a paper that has quietly changed what it rewards. The single most common pattern behind an A-to-A* gap is a revision routine calibrated to the first year and never recalibrated.
The practical implication is that the balance of a timetable should shift as well as its content. First-year revision can reasonably be weighted towards securing AO1, because AO1 is worth more there and because everything above it depends on it. Second-year revision that keeps the same balance is under-investing in the two objectives that grew.
The method that turns all of this into revision is a change to how a paper is marked, not to how it is sat. When you mark your own script, tag every lost mark with an objective rather than a topic.
An AO1 loss means you did not know something stateable: the reagent, the conditions, the colour of a complex, the definition, the observation. The fix is retrieval practice on a finite list, and it is the fastest of the three to close. An AO2 loss means you knew the chemistry and could not get it into the context on the page — you recognised that a Born-Haber cycle was wanted but could not build it for that compound. The fix is more unfamiliar contexts, not more notes. An AO3 loss means the data were in front of you and the judgement was not there. The fix is the writing exercise described above.
Two papers marked this way will usually show one objective carrying most of the loss, and that is the finding worth acting on. A topic list tells you that you are weak on transition metals; an objective tally tells you whether you are weak on transition metals because you cannot remember the colours or because you cannot interpret the data about them, and those two problems have nothing in common as revision tasks.
AQA makes this easier than the other boards by publishing notional component grade boundaries alongside the subject boundaries, so a paper can be scored on its own. In June 2026 an A* on Paper 1 fell at 91 of 105, on Paper 2 at 87 of 105, and on Paper 3 at 77 of 90. AQA is explicit that there is no official grade for a single component and that these are illustrative, but for self-marking they are the closest thing to a scoreboard a student has.
The evidence on which revision techniques actually move scores — retrieval practice, spaced study intervals and interleaving, with the measured effect sizes behind them — is set out in our guide to evidence-based revision techniques, and the same objective-tagging method transfers to other sciences, including GCSE Biology revision. For A-level Chemistry specifically, the practical question is what you point those techniques at, and the answer is on this page: the two thirds of the paper that never asked you to remember anything.
Every weighting on this page is published by the body that sets it. The permitted bands are in Ofqual's GCE subject-level conditions and requirements for science. The board figures are in the AQA Chemistry 7405 scheme of assessment, the OCR Chemistry A (H432) specification, the Pearson Edexcel Chemistry (9CH0) specification and the Eduqas Chemistry specification. The June 2026 boundaries are in AQA's published raw mark grade boundary tables. Where a mark figure on this page is arithmetic rather than a published number, the page says so.
If you want this applied to your own position rather than in general, A-level Chemistry tuition and the wider A-Level tuition pages explain how we work; students moving up from GCSE Chemistry will find the change in what the paper rewards steeper than the change in content.
Ofqual sets AO1, the recall objective, at 30 to 35 per cent of an A level science qualification, and every board sits inside that band: AQA 30 per cent, Edexcel 31 to 33 per cent, OCR Chemistry A 31 to 34 per cent, Eduqas 30.7 per cent. On AQA's 300 scaled marks that is about 90 marks. A student who could recall every definition, reagent, condition and colour in the specification, and do nothing else with it, would be playing for roughly three marks in ten.
Because content knowledge is the AO1 objective and AO1 is the smallest of the three. On AQA, AO2 application is about 135 marks and AO3 analysis and evaluation about 75, so 210 of the 300 marks ask you to do something with the chemistry rather than state it. The June 2026 A* boundary was 255 of 300. Even a candidate who took every AO1 mark would still need 165 of those 210 applied marks, which is just under 79 per cent of them.
The synoptic paper on every board. AQA's Paper 3 is 32 per cent AO1, 34 per cent AO2 and 34 per cent AO3, against 30, 48 and 22 on Papers 1 and 2, so roughly 31 of its 90 marks are AO3 against about 23 of 105 on each of the others. Edexcel's Paper 3 carries 13 to 15 per cent of the whole qualification as AO3 inside a paper worth 40 per cent, which is 33 to 38 per cent of that paper. Revising it by topic coverage misreads what it asks.
Less than most revision sites imply, at the level of assessment objectives. Ofqual sets AO1, AO2 and AO3 identically for every AS and A-level Chemistry specification and every board, and the published weightings differ by a few percentage points: AO2 runs 40 to 45 per cent on AQA, OCR, Edexcel and Eduqas alike. What genuinely differs is how the marks are cut into papers and what the data booklet supplies, which is set out on our A-level Chemistry subject guide.
By revising the reasoning rather than the procedure. AQA states that at least 15 per cent of the overall assessment assesses knowledge, skills and understanding in relation to practical work, which is at least 45 of its 300 marks, and Eduqas sets the same 15 per cent minimum for indirect practical assessment. Those marks sit inside AO2 and AO3, so the questions ask why a reagent was chosen, what the dominant source of uncertainty was, and how a method could be refined.
Yes, and Ofqual's own figures say why. At AS the required weightings are AO1 35 to 40 per cent and AO3 20 to 25 per cent. At A level they move to AO1 30 to 35 per cent and AO3 25 to 30 per cent. The qualification shifts away from recall and towards analysis across the two years, so a revision method that worked in the first year is being applied to a paper that rewards it less in the second.
Tag every lost mark by assessment objective rather than by topic. An AO1 loss means you did not know a reagent, condition or definition. An AO2 loss means you knew the chemistry and could not apply it to the context in front of you. An AO3 loss means you could not judge or evaluate the data. AQA publishes notional component boundaries so you can score papers separately: in June 2026 an A* was 91 of 105 on Paper 1, 87 of 105 on Paper 2 and 77 of 90 on Paper 3.
Send us two marked A-level Chemistry past papers and your exam board. A specialist chemistry tutor will tag every lost mark as AO1, AO2 or AO3, so you can see whether the shortfall is recall, application or evaluation, and then build the term around the objective that is costing the most. Sessions work from your own specification, and on AQA they are scored against the published notional component boundaries so progress is measured against the same numbers the examiners used. Rated 4.8/5 on Trustpilot.
Reviewed August 2026: assessment objective definitions and weightings were checked against Ofqual's subject-level conditions and the current AQA, OCR, Pearson Edexcel and Eduqas Chemistry specifications, and the mark arithmetic was checked against AQA's published June 2026 subject and notional component grade boundaries. Last updated 16 August 2026.
Tell us your exam board and send two marked past papers. A specialist chemistry tutor will tell you which assessment objective is costing you the most and build the term around it.
Rated 4.8/5 on Trustpilot. See also our A-level Chemistry subject guide and A-Level Tuition.
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