Question 1

What are OCR B (Salters) A-Level Chemistry grade boundaries?

Accepted Answer

The grade boundaries are the minimum raw marks required for each letter grade in OCR B (Salters) A-Level Chemistry (specification H433). OCR sets them once marking is complete for the whole cohort: senior examiners review evidence from the exam series, compare performance with previous years, and recommend where each boundary should sit. They're then normally published at 8am on A-Level results day, alongside the grades themselves.

Because each paper is a slightly different test. If a paper turns out more difficult than usual, the boundaries come down. If it's more accessible, they nudge up. The aim is that a grade represents the same standard whichever year you happened to sit the exam, even though the raw mark needed will vary between series.

Question 2

What does 'notional' mean on the per-paper table?

Accepted Answer

It's the technical word OCR uses for boundaries shown for illustration, rather than boundaries that formally decide a grade. Your OCR B (Salters) A-Level Chemistry grade is never awarded on a single paper on its own. It's always calculated from your total across all three papers combined.

The notional per-paper figures are still useful, because they help you interpret your marks on individual papers when you're doing past-paper practice. If you know a paper sat at a particular mark for an A* in one series, you have a reference point when you mark your own attempt. Just don't treat them as fixed cut-offs the way the overall boundaries are. The only boundary that formally decides your grade is the overall total across all three papers.

Question 3

Why do the OCR B (Salters) A-Level Chemistry boundaries change every year?

Accepted Answer

Because each paper is a slightly different test. Once marking is complete, senior examiners review evidence from the exam series, compare performance with previous years, and recommend where the boundaries should sit for each grade. If the paper turned out more difficult than usual, the boundaries come down. If it was more accessible, they nudge up.

The point of that adjustment is fairness across cohorts: a grade should mean the same thing whichever year you sat it. That's also why comparing raw marks across years can be misleading. A total of 165 out of 270 might have been a B in one series and an A in another, depending on how the papers landed.

Question 4

When are the OCR B (Salters) A-Level Chemistry grade boundaries published?

Accepted Answer

OCR normally publishes A-Level grade boundaries at 8am on A-Level results day, alongside the grades themselves. They land on OCR's grade boundaries page and cover every A-Level specification in a single PDF.

We update this page the same morning with the new row, so you can look up your total against the fresh boundaries and see what grade it would have earned.

Question 5

What mark do I need for an A* in OCR B (Salters) A-Level Chemistry?

Accepted Answer

It depends on the year, because OCR sets the boundaries once the cohort has been marked. In recent series, the A* boundary has sat between 205 and 221 marks out of 270 (roughly 76 to 82 percent). The exact figures per series are in the table above.

A sensible working target through your revision is to aim comfortably above the highest recent boundary in past-paper practice, which gives you some headroom for the exam room. Whether that translates to an A* in your specific series will depend on how the cohort performs overall and how the papers land.

Question 6

How should I use these boundaries when I'm revising?

Accepted Answer

There are two ways worth building into your routine.

**Score your past papers realistically.** Sit a paper timed, mark it against the official mark scheme, and if you've completed a full set of papers, compare your total against that year's overall boundary in the table above. That's the grade it would have earned in that series, and exactly how many marks you were short of the next one. Our [past papers by year](https://cognito.org/courses/alevel/chemistry/ocrb/past-papers/by-year) tab has every paper and mark scheme in one place, so you can pick a series and get straight into it.

**Set your target using an average.** A practical target is to aim around the average of the last few years' boundaries for the grade you're going for. That's more realistic than aiming at the highest recent year, in case the next paper is more difficult, and more ambitious than aiming at the lowest, in case it's more accessible.

Once you know where you're losing marks, our [structured exam practice](https://cognito.org/courses/alevel/chemistry/ocrb/exam-practice/structured) is grouped by topic so you can work through the areas that need the most attention. The wrong-answer mode on our quizzes and flashcards brings back the ones you got wrong so you can rework them a few days later.

Question 7

Can I use Cognito for OCR B (Salters) A-Level Chemistry exam practice?

Accepted Answer

Yes! Our full [A-Level Chemistry (OCR B (Salters)) course](https://cognito.org/courses/alevel/chemistry/ocrb) is free and covers the whole H433 specification. You'll find revision notes written to the spec, self-marking quizzes and flashcards, [structured exam questions](https://cognito.org/courses/alevel/chemistry/ocrb/exam-practice/structured) grouped by topic with worked answers in mark-scheme style, and [past papers by year](https://cognito.org/courses/alevel/chemistry/ocrb/past-papers/by-year) with the official mark schemes alongside.

A sensible order once you're deep into revision: work through a topic in the notes, test yourself with the quiz and flashcards, then have a go at the structured exam questions on that topic. Come back to full past papers under timed conditions in the final weeks before your exam.

Series	Max	Grade A*	Grade A	Grade B	Grade C	Grade D	Grade E
Jun 2025Latest	270	216	176	146	117	88	59
Jun 2024	270	221	186	156	127	98	69
Jun 2023	270	211	177	146	115	84	53
Jun 2022	270	205	165	134	103	73	43

A-Level Chemistry OCR B (Salters) Grade Boundaries

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