Exam Time Management: Papers 1 and 3 (Core)
How to pace IGCSE Chemistry 0620 Core papers: per-question timing for Paper 1 (40 questions in 45 minutes) and section pacing for Paper 3 (80 marks in 75 minutes).
Published by IGCSEChemistry.com.my
Chemistry teaching team: K. S. Tan (15+ years teaching IGCSE Chemistry) and Ms Yash (10+ years teaching IGCSE Chemistry) and Ms Kartini (15+ years teaching IGCSE Chemistry).
Mapped to Cambridge IGCSE Chemistry 0620 (2026–2028). Last updated 2026-08-24.
Core candidates sit two written papers: Paper 1 (multiple choice) and Paper 3 (structured theory), plus a practical component. They fail different candidates in different ways. Paper 1 punishes the student who lingers; Paper 3 punishes the student who over-writes. This guide gives the pacing arithmetic for both. If you are unsure which papers you sit, check which paper am I taking first.
Paper 1: the arithmetic
Paper 1 is 40 questions in 45 minutes, one mark each, no partial credit, no negative marking.
- 45 minutes ÷ 40 questions = 67.5 seconds per question
- factual questions (definitions, properties, observations): 20-40 seconds
- data-interpretation and calculation questions: 60-90 seconds
- aim to finish with 3-5 minutes to spare for review
The pace only works if your Core facts are at instant recall. Thirty seconds spent recalling the colour of copper(II) hydroxide is thirty seconds stolen from a later question. Build that recall with flashcards before the exam, not in the hall.
The three-pass approach for Paper 1
First pass (about 30 minutes). Work through questions 1-40 in order. Answer everything you can settle within 60 seconds. For anything harder, eliminate the wrong options, record your best guess, circle the number and move on. Leave no blank on the first pass — if time runs out later, every question still has an answer.
Second pass (about 10 minutes). Return to the circled questions. Re-read each stem for a missed word such as “not” or “least”. Change an answer only for a specific reason, never because it “feels wrong”.
Third pass (about 5 minutes). Scan the answer sheet: every question answered, each mark on the intended row, and one or two calculations re-checked.
The Paper 1 time traps
- The question you “almost know”. If it will not come within 30 seconds, guess and move on. One mark is not worth two minutes.
- The double negative. “Which statement is not incorrect” is deliberately confusing. Underline the negatives and work option by option, but cap it at about 90 seconds.
- Multi-step arithmetic in your head. Write the working on the paper; you are allowed to. A single written line prevents most power-of-ten and ratio slips.
Paper 3: the arithmetic
Paper 3 is 80 marks in 1 hour 15 minutes of structured theory, no negative marking.
- 75 minutes ÷ 80 marks = about 56 seconds per mark
- a one-mark “state” answer should take far less; a four-mark calculation, more
- reserve the final 5-8 minutes for blanks, units, equations and graph readings
The mark allocation, not the clock, sizes each answer. A two-mark question wants two creditable points and then you move on; polishing it into a paragraph spends a later question’s time.
Section pacing for Paper 3
Paper 3 is a booklet of structured questions of rising demand. A workable split of the 75 minutes:
| Phase | Time | What you are doing |
|---|---|---|
| Early questions | first ~25 min | Shorter recall and one-step items. Bank these marks quickly and do not dawdle |
| Middle questions | next ~30 min | Multi-part questions, calculations, descriptions. Show working; match points to marks |
| Later questions | next ~12 min | The most demanding parts and any longer explanations. Attempt every part even if unsure |
| Review | final ~8 min | Fill blank lines, check units and equations, re-read one or two calculations |
Two rules keep this on track:
- Never leave an answer line blank on the first pass. An attempted deduction can score; a blank cannot.
- Flag and move. If a subpart stalls you for more than about 90 seconds, mark it and continue. A single stubborn calculation must not cost you three later marks.
The Paper 3 over-writing trap
The most common Paper 3 timing failure is not slowness on hard questions; it is writing a full paragraph for a one- or two-mark item. Count the marks, give that many distinct points, and stop. The extra sentences earn nothing and quietly consume the minutes the later questions need.
Practising the pace
Do at least four or five full timed sets of each paper before the exam. After each one:
- Note your finishing time. Finishing Paper 1 in 35 minutes means you can afford more care; running past 45 means a question type is too slow.
- Record where time was lost on Paper 3: one hard calculation, or over-writing throughout? The two need different fixes.
- Classify the errors, not just the total, using the method in common exam mistakes.
The Core and Extended papers share timing arithmetic, so the Paper 2 timing guide and Paper 4 timing guide use the same structures if a route change is on the table.
Next steps
Pair this with the Paper 1 multiple-choice (Core) guide and the Paper 3 theory (Core) guide for answer technique, use the free diagnostic to find weak topics, and run timed sets from the topical questions and practice hub.