What is the best way to mark your own IGCSE Chemistry past papers?

The best way to mark your own Cambridge IGCSE Chemistry past papers is to run a structured mark scheme audit, not a casual read-through of correct answers.

Print the official Cambridge mark scheme alongside your completed paper. Go through each question point by point. Do not award partial credit to yourself based on what you meant to write.

Every time you lose a mark, sort the error into one of three categories:

• Knowledge gap: you did not know the content
• Keyword omission: you knew the concept but used the wrong phrasing
• Calculation error: your method or arithmetic was wrong

Keyword omissions are the fastest to fix. Cambridge mark schemes require precise language. Phrases such as "increased collision frequency" or "delocalised electrons" must appear verbatim in some answers. A broadly correct explanation without the required term earns zero for that point.

Build a vocabulary list of required mark scheme phrases, organised by topic. Review it the evening before each practice paper run. Students who work through this process with a tutor during online tutoring sessions consistently close one to two mark bands through keyword literacy alone.

Calculation errors need a different fix. After each full paper run, note where your pacing broke down and which steps you skipped under time pressure. Paper 2 calculation questions and the Alternative to Practical paper are the most common pacing trouble spots for students targeting the A* boundary.

The system works best across three phases: open-book topical practice first, then timed full paper runs, then mark scheme audits after each session. Skipping the audit phase is why many students plateau despite completing multiple papers.

For a full breakdown of all three phases, including what to do in each session and how many papers to complete, see our blog guide on using IGCSE Chemistry past papers to score an A*. If you want a tutor to review your mark scheme errors session by session, contact us and we will match you with a specialist within ten minutes.