WJEC A-level Chemistry: the four units, the practical and 2027 dates

WJEC A-level Chemistry: the specification

WJEC GCE AS and A level Chemistry is a Welsh Government accredited qualification, first taught in 2015, and the specification says it is not available to centres in England. Eduqas, WJEC's English brand, has its own A level: see our Eduqas A-level Chemistry guide. The AS can be taken alone.

WJEC A-level Chemistry units

The papers use short answer, structured and extended response questions, and a data booklet with the Periodic Table is provided, as our WJEC A-level Chemistry data booklet guide explains. Dates are from WJEC's final summer 2027 timetable; see the WJEC A-level timetable 2027. The main themes for the Unit 5 practical are shared with schools early in each spring term.

What each unit covers

• AS 1: formulae and equations, basic ideas about atoms, chemical calculations, bonding, solid structures, the Periodic Table, and simple equilibria and acid-base reactions.
• AS 2: thermochemistry, rates of reaction, the wider impact of chemistry, organic compounds, hydrocarbons, halogenoalkanes, alcohols and carboxylic acids, and instrumental analysis.
• A2 3: redox and electrode potentials, the p-block and d-block, chemical kinetics, enthalpy changes for solids and solutions, entropy and feasibility, equilibrium constants and acid-base equilibria.
• A2 4: stereoisomerism, aromaticity, alcohols and phenols, aldehydes and ketones, carboxylic acids and derivatives, amines, amino acids, peptides and proteins, and organic synthesis and analysis.

Worked examples in WJEC style

AS: a titration calculation

A 25.0 cm³ portion of sodium hydroxide solution needs 21.60 cm³ of 0.100 mol dm⁻³ hydrochloric acid to neutralise it. The reaction is 1 : 1, so first the moles of acid:

Give the answer to 3 significant figures, 0.0864 mol dm⁻³, to match the burette readings.

A2: pH of a strong acid

A solution of hydrochloric acid has [H⁺] = 0.025 mol dm⁻³. A strong acid is fully ionised, so:

WJEC A-level Chemistry grades

Each unit is changed to a uniform mark; the AS totals 200 and the A level 500.

An A* needs an A overall (400 uniform marks) and at least 90% of the uniform marks for the A2 units, which is 270 out of 300. At AS the grades are A to E. A unit result is reported as a lower case letter a to e on the results slip, not on the certificate. See A-level grades explained.

Use the daily papers as short timed mocks for WJEC A-level Chemistry

Uni-Sine publishes a new free daily paper on each track: A-level Chemistry Year 1 and A-level Chemistry Year 2. It is a short timed mock: 8 questions worth 25 to 35 marks, marked instantly, with worked answers. It is not a full exam paper and it is not written by the exam board, so use it as a quick timed practice test alongside the board's own specimen and past papers.

• What it covers well: amount of substance, enthalpy, equilibria, redox, kinetics, bonding, organic chemistry and periodicity in Year 1, and buffers, electrode potentials, transition metals, entropy, aromatic and carbonyl chemistry and spectroscopy in Year 2.
• What it does not cover: the practical Unit 5, and the WJEC specific emphasis on instrumental analysis and organic synthesis. Use WJEC past papers for those.

Time one daily paper, mark it hard, then do a full WJEC unit paper each week as the exam approaches.

Exam answers

Uni-Sine does not publish official answers, past paper answers or mark schemes from the exam board. The answers and a worked mark scheme for each daily paper come with that day's paper once it is marked, so you can see where every mark was won or lost.

Common mistakes in WJEC A-level Chemistry

• Mixing up volumes in titrations. Convert cm³ to dm³.
• Forgetting the mole ratio. A 1 : 1 reaction is the exception, not the rule.
• Using the data booklet badly. Look up the value before you start, not at the end.
• Rounding pH too early. Round only the final line.

Read next

UK · A-levelWJEC A-level Chemistry grade boundaries 2026WJEC A-level Chemistry 2026 boundaries: raw marks for each of the five units, the fixed UMS totals, the A* rule and what changed since 2025.