Q: What does Cambridge IGCSE Chemistry Paper 6 assess? A: Paper 6 is the one-hour Alternative to Practical paper. Candidates do not perform experiments during the paper, but Cambridge tests the same AO3 experimental skills and chemistry contexts as Paper 5.
TL;DR For the 2026-2028 Chemistry syllabuses, Paper 6 has 40 marks, contributes 20%, and contains compulsory items. It tests practical reasoning through written material rather than candidate-run experiments. Confirm the syllabus code and component entry with the examination centre instead of assuming that private-candidate status automatically means Paper 6.
Last reviewed: 24 July 2026. This guide is bounded to Cambridge's published 0620 and 0971 specifications. The syllabuses define assessable skills and contexts, but they do not publish the exact experiments or question order for a future paper.
12 noon to 2pm, 2pm to 4pm, 4pm to 6pm, or 6pm to 8pm
Jurong East Centre (Vision Exchange)
Weekdays
12 noon to 2pm or 2pm to 4pm
Weekends
6pm to 8pm or 8pm to 10pm
Timings last updated: 17 July 2026. Confirm the venue and exact session before travelling.
Pricing
No
Question status
All items compulsory
Alternative route
Paper 5 Practical Test, 1 hour 15 minutes
All candidates take one practical paper from a choice of Paper 5 or Paper 6. Cambridge says both papers require the same experimental skills, require understanding of the same experimental contexts, and test the same assessment objective.
The papers are not identical. Paper 5 requires candidates to perform experiments in a laboratory. Paper 6 presents practical work through questions, apparatus diagrams, observations, readings, tables, graphs, or other supplied material.
2. Confirm the entry before choosing resources
Do not infer the practical paper from whether the candidate studies privately, attends an international school, or has access to a laboratory elsewhere. The examination centre makes and administers the entry.
Ask the centre to confirm in writing:
the syllabus code, 0620 or 0971;
the examination series and administrative zone;
whether the entry uses Paper 5 or Paper 6;
the final component code on the Statement of Entry;
any centre deadlines and local arrangements.
Cambridge describes 0971 as graded 9 to 1 and otherwise the same as 0620. Its current overview limits availability to specified administrative zones and locations. Use the live availability notice and the candidate's actual entry rather than a general assumption about country, school type, or candidate status.
Cambridge says additional 0620 past papers may be useful for teaching 0971. That does not change the syllabus code, component code, series, or grading scale on a candidate's entry.
3. The AO3 skills Cambridge may assess
The current syllabus groups the practical requirements into five areas.
Selecting and safely using techniques, apparatus, and materials
Candidates may need to identify or label apparatus, explain a common technique, choose and justify a method, describe a qualitative or gas test, address a hazard, or explain how observation and data accuracy can be improved.
Planning experiments and investigations
The specification includes identifying independent and dependent variables, explaining controlled variables, choosing a suitable number and range of values, justifying apparatus, describing a procedure, identifying risk, recording and processing results, and making a reasoned prediction.
Cambridge does not publish one mandatory planning template or state that every response must begin with a separately labelled hypothesis. Answer the particular task and give the method, measurements, controls, safety decisions, and processing detail being assessed.
Making and recording observations, measurements, and estimates
Candidates may read analogue or digital apparatus or diagrams, read to the nearest half-scale division where required, take sufficient measurements, repeat readings where appropriate, record qualitative chemical-test observations, and organise results with suitable units and precision.
Interpreting and evaluating observations and data
This includes calculations, graphing, best-fit lines where appropriate, interpolation, extrapolation, gradients, intercepts, conclusions supported by observations and data, identification of anomalies, and appropriate action on anomalous results.
Evaluating methods and improvements
Candidates may evaluate arrangements, methods, techniques, and control of variables, identify a specific source of error, and suggest an improvement to the apparatus or procedure. A phrase such as "human error" does not identify which observation, measurement, or step is limited.
4. Published experimental contexts
Cambridge says candidates should be familiar with practical work involving:
measurement of gas or liquid volumes, masses, temperatures, times, and lengths;
rates of reaction and salt preparation;
filtration, crystallisation, simple and fractional distillation, and chromatography;
electrolysis and identification of metal ions, non-metal ions, and gases;
tests for water, dilute acids, oxidising agents, and reducing agents;
heating and cooling curves, temperature changes, titrations, and solubility;
melting and boiling points, displacement reactions, rusting, and corrosion;
unfamiliar procedures using simple apparatus.
These are syllabus contexts, not a guaranteed future-paper pattern. The specification does not promise one titration, one qualitative-analysis task, one rates graph, one energetics calculation, and one planning question in every paper.
5. Qualitative analysis notes
Cambridge provides its Notes for use in qualitative analysis for both Paper 5 and Paper 6. The current notes cover prescribed tests and observations for anions, aqueous cations, gases, and flame tests.
Use the version supplied for the examination. Read the full test sequence and observation from the table rather than relying on a colour word alone. A result such as a precipitate colour may not identify an ion unless the stated reagent, order, excess-reagent behaviour, gas test, or other observation is also considered.
The syllabus expects candidates to be able to describe qualitative, gas, and other tests. Provision of the notes does not establish that every listed ion or gas will be tested in a particular paper, and it does not justify replacing the supplied table with an older memorised version.
6. Readings, tables, and calculations
Cambridge publishes data-recording conventions.
Read an instrument to one half of its smallest division where interpolation is required.
Record values at the precision supported by the measuring instrument.
Put the quantity and unit in a table heading, such as time / s.
Repeat and record readings where appropriate.
Do not include units in the body of a table.
Use significant figures appropriate to the raw data and instrument.
Give a calculated quantity the same number of significant figures as the least precise raw value used in that calculation.
Do not impose one universal titration, rate, or energy-calculation routine. The question and supplied apparatus determine the required precision, readings, averaging, equation, constants, sign, and units. A fixed concordance threshold, forced two-decimal-place rule, tangent at zero, heat-capacity value, or mass assumption is not a syllabus-wide instruction for every task.
7. Graphs
The current Chemistry specification gives these conventions.
Label axes with the measured or calculated quantity and unit.
Unless instructed otherwise, plot the independent variable on the horizontal axis and the dependent variable on the vertical axis.
Unless instructed otherwise, use more than half the grid in both directions and choose a sensible scale.
Mark points as crosses or encircled dots of suitable size and plot within half a smallest square.
Draw a single thin, smooth best-fit straight line or curve.
Where data are scattered, place the best-fit line with a roughly even distribution of points on either side over its length.
Ignore a clearly anomalous point when drawing the best-fit line, but identify it as anomalous.
Read a line, intercept, interpolated value, or extrapolated value to the precision supported by the grid.
For the gradient of a straight line, mark a triangle whose hypotenuse spans at least half the length of the candidate's best-fit line.
Do not force a straight line, origin, tangent, or gradient calculation unless the data and question require it.
8. A source-bounded preparation method
The following is study advice, not a Cambridge rule.
Verify the syllabus and component code before selecting papers.
Use the current specification to tag each error by AO3 skill: technique, planning, observation, data, or evaluation.
Practise reading the apparatus or diagram actually supplied and recording at supported precision.
Use the current qualitative-analysis notes to connect the stated test sequence to the complete observation.
Redraw tables and graphs using Cambridge's published conventions.
For a plan, connect the variable, method, measurement, control, safety step, and result-processing method to the actual task.
For an evaluation, name the limited step, explain its effect, and propose a change that addresses that limitation.
Cambridge expects candidates to develop experimental skills and be familiar with common apparatus and reagents whether they take Paper 5 or Paper 6. Practical experience can support understanding, but the syllabus does not require one commercial course, provider, mock schedule, or fixed number of laboratory sessions.
Worked application: read a supplied rate graph as practical evidence
A Paper 6 graph shows two gas-volume curves reaching the same 60 cm3 plateau, but curve A is steeper near time zero. The defensible conclusion is that A has the greater initial rate while both runs produce the same measured final gas volume. A candidate should not say that A makes more gas or assume a catalyst without information about the changed variable. If asked for initial rate, draw a tangent at the specified point, use a large triangle and report volume per time. If a loose bung is shown, explain that escaping gas makes recorded volumes too low and propose checking airtight joints before reagents are mixed.
Common misconceptions and corrections
Calling Paper 6 easier because no experiment is performed. It tests the same AO3 skills through supplied evidence.
Assuming private-candidate status automatically selects Paper 6. Confirm the component with the centre.
Memorising one past-paper order. Published contexts do not guarantee a future pattern.
Ignoring apparatus diagrams because the data are supplied. Diagram details often control interpretation.
Reading the wrong scale direction. Trace labels and scale values before recording.
Inventing decimal places from a printed diagram. Use the resolution shown.
Putting units in each table body cell. Put them in headings.
Naming a gas without its test result. State procedure, observation and conclusion.
Using one precipitate colour as complete identification. Include reagent order and excess behaviour.
Forcing a straight line through curved data. Choose the form supported by the points.
Joining points dot to dot. Use an appropriate best-fit line or curve.
Forcing a graph through the origin. Do so only when instructed or justified.
Ignoring a plotted anomaly silently. Identify it and apply the requested treatment.
Using two nearby points for a straight-line gradient. Use a triangle spanning at least half the best-fit line.
Confusing interpolation with extrapolation. One reads within the data range; the other extends beyond it.
Calling a shorter endpoint time a lower rate. For the same endpoint, reciprocal time is greater.
Writing “human error” in evaluation. Name the specific flawed reading or step.
Suggesting a more precise instrument without explaining why. Connect resolution to the measured difference.
Treating repeats as a fix for leakage. Repair the systematic fault first.
Inventing a universal titration or calorimetry rule. Follow the supplied apparatus, data and instruction.
Assessment guidance
Paper 6 rewards reconstruction of what the experiment means from diagrams, tables, observations and graphs. Annotate the changed variable, measured outcome and controlled quantities before answering. Read every instrument from its displayed scale, preserve raw precision and show calculation substitutions with units. Use the current qualitative-analysis table as a complete sequence rather than a colour list. Planning answers need a reproducible method and explicit data-processing route. Evaluation answers should connect a named limitation to the direction or type of data damage and then to a feasible correction. Never infer an unreported observation or expected result merely to make the data look ideal.
Retrieval practice
Reconstruct the five AO3 areas and the published experimental contexts. Read fifty printed instrument scales, complete tables and process repeats. Interpret qualitative-analysis sequences from reagent to conclusion. Plot straight and curved datasets, identify anomalies, interpolate, extrapolate and calculate gradients. Redraw faulty apparatus, write ten investigation plans and produce twenty limitation-effect-improvement chains from unfamiliar scenarios without relying on a memorised past-paper order.
13. What this guide does not establish
The syllabuses do not establish:
which component a particular Singapore centre will offer;
that all private candidates take Paper 6;
the exact apparatus, experiment, or question order in a future paper;
a guaranteed titration, qualitative-analysis, rates, or energetics pattern;
universal burette, concordance, tangent, or calorimetry rules for every question;
a fixed past-paper, mock, or laboratory-session requirement;
grade improvement from laboratory tuition or any other preparation format.
Use the syllabus for the assessment contract, the centre for the candidate's entry, and live examination documents for series-specific administration.
