Advanced Higher Chemistry
Advanced Higher Chemistry now has a 100-mark, 2 hour 30 minute exam and a 25-mark project scaled to 34. The 2027 exam is on Friday 21 May, 9:00 to 11:30.
- Question paper09:00 to 11:30
What grade is my mark?
Type a total mark to see the grade it would have got.
How the A and C boundaries have moved
Boundaries as a share of the total marks. A lower line means the papers were judged harder that year. Qualifications Scotland publishes boundaries from 2022 in this format.
| Year | Out of | A | B | C | D |
|---|---|---|---|---|---|
| 2026 | 160 | 108 | 90 | 73 | 55 |
| 2025 | 160 | 108 | 92 | 76 | 60 |
| 2024 | 160 | 104 | 88 | 72 | 56 |
| 2023 | 120 | 77 | 62 | 48 | 33 |
| 2022 | 120 | 77 | 62 | 48 | 33 |
Changes from session 2026/27
The question paper was cut from 110 marks to 100 and from 3 hours to 2 hours 30 minutes. Section 1 still has 25 objective test marks. Section 2 now has 75 marks instead of 85. Scaling was removed from the paper.
The project still has 25 marks but is now scaled to 34 instead of 40. The course total is therefore 134 marks, with the exam about three quarters of it.
Inside the paper
Section 1 is a 25-mark objective test. Section 2 mixes calculations, structured questions and longer explanations across all four areas. Researching chemistry questions test practical techniques, so lab experience pays off in the exam as well as the project.
The project
You carry out an investigation with a chemistry focus and write it up. The report should be 2,500 to 4,500 words, not counting front matter, tables, graphs and references. A penalty applies if it runs more than 10% over. The course specification recommends 10 to 15 hours of experimental work.
Aims should stay on the chemistry you test in the lab. The 2025 report advised against aims built around the word purity. It also warned against padding the report with history or biology.
Where 2025 candidates struggled
Candidates were confident with emission spectra, buffer pH, reaction orders and enthalpy. In Section 2, racemic mixtures, hydronium ion calculations and titration-based mass calculations went well.
Harder topics were:
- explaining colour differences between two transition metal complexes
- d orbital splitting in tetrahedral complexes
- the effect of optical isomers on plane-polarised light
- indicator colour changes explained through conjugation
- aldol reactions and spotting alpha hydrogen atoms
In projects, most abstracts stated the aim and findings. Risk assessments were the weak point, often missing hazards of indicators or the state and concentration of chemicals.
The report pointed out that many marks reward statements learned from the course specification. It also stressed hands-on practice with apparatus for researching chemistry questions. For data, it advised processing duplicate results separately before averaging.
Using past papers
Older papers had 110 marks in 3 hours. Practise them at a slightly faster pace to match the new paper. After marking, sort errors into knowledge gaps, explanation gaps and calculation slips, then target each list.
Revision checklist
Tick topics as you revise. Ticks are saved on this device only.
- Learn the definitions and statements in the course specification word for word.
- Explain colour in transition metal complexes using d orbital splitting, for octahedral and tetrahedral shapes.
- Practise optical isomer questions and explain the effect on plane-polarised light.
- Link indicator colour change to conjugation in organic molecules.
- Draw aldol reaction mechanisms and circle the alpha hydrogen atoms.
- Do buffer, equilibrium and kinetics calculations each week.
- Write a full risk assessment with hazards, concentrations, states and control measures.
- Keep your project aim on the chemistry you measure, avoiding the word purity.
- Process duplicate results separately before averaging in your project.
- Keep the project report between 2,500 and 4,500 words.
Quick answers
- How long is the Advanced Higher Chemistry exam in 2027?
2 hours 30 minutes, down from 3 hours. The paper now has 100 marks.
- How is the Advanced Higher Chemistry project marked?
It is marked out of 25 and scaled to 34, out of a course total of 134.
- What is the project word count?
2,500 to 4,500 words, excluding front matter, tables, graphs and references.
- When is the Advanced Higher Chemistry exam in 2027?
Friday 21 May 2027, 9:00 to 11:30.