AQA A-Level Chemistry: Paper-by-Paper Exam Preparation

AQA A-Level Chemistry (7405) is assessed through three written papers, not tiered: Paper 1 (relevant physical chemistry plus inorganic chemistry, plus practical skills, 2h, 105 marks, 35%), Paper 2 (relevant physical chemistry plus organic chemistry, plus practical skills, 2h, 105 marks, 35%), and Paper 3 (any content, any practical skills, 2h, 90 marks, 30%). These notes turn that structure into an exam-day plan, alongside the Atomic Structure and Mole Concept topic revision notes already on the site.

Know which physical chemistry sections sit under Paper 1 vs Paper 2

Physical chemistry is split unevenly across Paper 1 and Paper 2 – some physical chemistry sections pair with inorganic content on Paper 1, others pair with organic content on Paper 2. Exam-preparation priority: build an explicit checklist mapping each physical chemistry topic to Paper 1 or Paper 2 before revising, since assuming all physical chemistry belongs to one paper risks under-revising content for the other.

Paper 3 tests the whole specification, including 30 marks of multiple choice

Paper 3 draws on any content from across the whole course, split into 40 marks of practical techniques and data analysis, 20 marks of questions testing across the specification, and 30 marks of multiple choice. Exam-preparation priority: because Paper 3’s multiple-choice section still tests genuine understanding (not simple recall), and because the paper is whole-specification, leave dedicated whole-course review time before Paper 3 rather than assuming Paper 1 and Paper 2 revision alone will cover it.

Calculations reward shown method, not just a final answer

Mole-based, concentration and other numerical calculations recur across all three papers. Exam-preparation priority: practise showing every step of a calculation, including units at each stage, since partial credit is available for correct method even when a final numerical answer is wrong – but only if that method is actually written down.

Practical skills and data analysis carry real weight on Paper 3

40 of Paper 3’s 90 marks are dedicated to practical techniques and data analysis, drawn from across the required practicals. Exam-preparation priority: revise each required practical’s method, apparatus, and how to evaluate an unfamiliar variation of it – including identifying and reducing sources of error – as a distinct, heavily weighted revision strand, not an afterthought to content recall.

Worked practice scenario: a concentration calculation, every step shown

Question: “25.0 cm3 of a solution of sodium hydroxide was exactly neutralised by 20.0 cm3 of 0.100 mol dm-3 hydrochloric acid. Calculate the concentration of the sodium hydroxide solution.”

Step 1 - find moles of HCl used:
moles = concentration x volume (in dm3) = 0.100 x (20.0/1000) =
0.00200 mol

Step 2 - use the reaction's 1:1 mole ratio (NaOH + HCl -> NaCl + H2O):
moles of NaOH = moles of HCl = 0.00200 mol

Step 3 - convert the NaOH volume to dm3:
25.0 cm3 = 25.0/1000 = 0.0250 dm3

Step 4 - calculate the concentration of NaOH:
concentration = moles / volume = 0.00200 / 0.0250 = 0.0800 mol dm-3

Every step is shown – moles of the known reagent, the mole ratio from the balanced equation, unit conversion, and the final concentration calculation – which is exactly the level of working a titration calculation rewards, regardless of which specific acid-base pair is used.

Before/during exam checklist

• Before the exam: build a checklist mapping physical chemistry sections to Paper 1 or Paper 2; leave dedicated whole-specification review time before Paper 3; practise calculations showing every step and unit; revise required practicals’ methods and error-evaluation as a distinct, heavily weighted revision strand for Paper 3.
• During Paper 1: expect physical chemistry questions to be paired with inorganic content.
• During Paper 2: expect physical chemistry questions to be paired with organic content.
• During Paper 3: treat the multiple-choice section as a genuine test of understanding, not a guessing exercise, and expect practical-technique and data-analysis questions to carry substantial marks.
• On every paper: show every step of a calculation with units, even when the arithmetic feels simple enough to skip.

Self-test

1. Why is it worth mapping physical chemistry sections to Paper 1 or Paper 2 explicitly?
2. What makes Paper 3 different in scope from Paper 1 and Paper 2?
3. Why should every step of a calculation be shown, even for simple arithmetic?
4. In the worked scenario, why is the mole ratio between NaOH and HCl needed before calculating the final concentration?

Answers: 1. Because physical chemistry is split unevenly across the two papers – some sections pair with inorganic content on Paper 1, others with organic content on Paper 2 – so assuming it all belongs to one paper risks under-revising the other. 2. Paper 3 draws on any content from across the whole specification, unlike Paper 1 and Paper 2, which are each scoped to specific physical chemistry sections plus inorganic or organic chemistry respectively. 3. Because partial credit (method marks) is available for correct working even when the final numerical answer is wrong, but only if that working is actually written down. 4. Because the balanced equation’s 1:1 mole ratio converts moles of the known reagent (HCl) into moles of the unknown reagent (NaOH) – skipping this step and using the wrong number of moles would give an incorrect final concentration.

Written against AQA A-Level Chemistry 7405 (specification-at-a-glance, verified 2026-08-28). The worked scenario above is an original example written for this resource, not a reproduction of any official past or sample paper question. Always check the current specification for your examination year at aqa.org.uk.