Grade 12 · Physical Sciences · Chemistry, Paper 2 · CAPS
Quantitative Chemistry (Stoichiometry) Revision – Grade 12 Physical Sciences (Chemistry, Paper 2)
What Stoichiometry covers, how it is examined in Physical Sciences Paper 2 (Chemistry), the 4 sections to study and how long it takes – plus live online lessons when you get stuck.
- Study sections
- 4
- Exam-style questions
- 9
- Marks of practice
- 65
- Study time
- ≈ 3 h 50 min
What it covers
Stoichiometry has no question of its own, but you need it for the calculations in the rate, equilibrium, acid-base and electrochemistry work. This revision topic sharpens the mole calculations those questions depend on: moles from mass, gas volume and concentration, limiting reagents, percentage yield and purity, and empirical formulae, so that the calculation steps in the rest of Paper 2 go smoothly.
How it is examined
- Paper
- Physical Sciences Paper 2 (Chemistry) – Monday 2 November 2026, 09:00 (3 hours, 150 marks)
- Weighting
- Chemical change ≈ 92/150 (no separate question – stoichiometry is embedded in rate, equilibrium, acids/bases and electrochemistry calculations, ≈ 10–15 marks in total)
- Questions
- It does not get its own question: in a typical paper its calculations sit inside Questions 5–9 of Physical Sciences Paper 2 (Chemistry).
Question numbers and mark splits are typical, not fixed – they vary a little from year to year.
Sections to study
- The mole: mass, gas volume and concentration30 min
- Balanced equations and limiting reagents40 min
- Percentage yield and percentage purity35 min
- Empirical and molecular formulas; gas volume ratios35 min
Study time
| Notes and worked examples4 sections | 2 h 20 min |
|---|---|
| Exam-style questions9 questions · 65 marks × 1,2 min per mark | 1 h 20 min |
| Topic quiz | 10 min |
| Total | ≈ 3 h 50 min |
Physical Sciences Paper 2 (Chemistry) is written on Monday 2 November 2026 at 09:00.
What you get in the portal
- 9 exam-style questions on Stoichiometry (65 marks in total), each with a full marking memo
- Worked examples with diagrams and step-by-step calculations for each of the 4 sections
- Tutor notes added to sections and questions – for the whole class or just for you
- A topic quiz, mock papers and a study plan that counts down to Physical Sciences Paper 2 (Chemistry)
Notes, worked examples, questions and memos open once the tutor approves your account – usually with your first confirmed lesson.
Stuck on Stoichiometry? Book a one-on-one lesson.
R250 per hour – 60, 90 or 120 minutes, online from anywhere in South Africa. Pick Stoichiometry as your topic; you pay by EFT only after the tutor confirms.
Related Chemistry P2 topics
- Organic Molecules: Structure and Naming
- Physical Properties of Organic Molecules
- Organic Reactions
- Rate and Extent of Reaction
All Grade 12 Physical Sciences topics, weighting and study time
Questions about Stoichiometry
How many marks is Stoichiometry worth in the matric exam?
In Physical Sciences Paper 2 (Chemistry) (3 hours, 150 marks) the usual weighting is: Chemical change ≈ 92/150 (no separate question – stoichiometry is embedded in rate, equilibrium, acids/bases and electrochemistry calculations, ≈ 10–15 marks in total). It does not get its own question: in a typical paper its calculations sit inside Questions 5–9 of Physical Sciences Paper 2 (Chemistry). The exact marks change a little from year to year.
How long does it take to study Stoichiometry?
About 3 h 50 min: 2 h 20 min for the notes and worked examples in its 4 sections, 1 h 20 min for the 9 exam-style questions (65 marks) at exam pace of 1,2 minutes per mark, and a 10-minute quiz.
When is the Physical Sciences Paper 2 (Chemistry) exam in 2026?
Physical Sciences Paper 2 (Chemistry) is written on Monday 2 November 2026 at 09:00 and lasts 3 hours (150 marks), according to the DBE’s 2026 NSC timetable. Confirm the date with your school, because the DBE can amend the timetable.
Can I get online lessons for Stoichiometry?
Yes. Create a free account in the Adventuity portal, request a one-on-one online lesson of 60, 90 or 120 minutes (or a seat in a group class) and choose Stoichiometry as your topic. You pay by EFT only after the tutor confirms the booking.