Which topic carries the most marks in the VCE Chemistry external exam?

What are the current and future options for supplying energy? carries 26.2% of the marks across the 9 VCAA papers from 2020 to 2025, ahead of How can the rate and yield of chemical reactions be optimised? on 25.1%.

How are marks split between question types in the VCE Chemistry exam?

Short answer carries 74.4% of the marks, multiple choice carries 25.0% of the marks and extended response carries 0.6% of the marks, measured across 9 papers and 1078 marks from 2020 to 2025.

Has the topic balance changed in recent VCE Chemistry papers?

No. Comparing the 2020 to 2022 papers with the 2023 to 2025 papers, the largest movement in any topic's share was 1.4 percentage points, which is too small to plan revision around.

How many past papers is this VCE Chemistry analysis based on?

9 VCAA external papers from 2020 to 2025, covering 352 questions and 1078 marks. 5.0% of those marks carry no dot-point mapping and sit outside the percentages.

VCE Chemistry most tested topics

Across the nine VCAA Chemistry external papers from 2020 to 2025, What are the current and future options for supplying energy? carries 26.2% of the marks against 9.2% for How is scientific inquiry used to investigate the sustainable production of energy and/or materials?, so the paper rewards What are the current and future options for supplying energy? more than any other topic. At dot-point level 4.1.2.1 carries 7.6% of paper marks, and two of the 68 dot points that the board assesses externally have not appeared in one of these papers. Every percentage below covers the 95.0% of marks that map to a study design dot point.

Computed from 9 VCAA Chemistry external papers, 2020 to 2025: 352 questions, 730 question parts and 1078 marks.

Unit, topic and dot-point shares below are of the 1024 marks that map to a dot point, so each of those tables adds to 100%. 213 of the 730 parts are assessed against more than one dot point, and their 330 marks are divided evenly between the dot points they cover.

What these papers are

Year	Exam	Questions	Marks
2025	Exam	37	120
2025	Exam (NHT)	40	120
2024	Exam	39	120
2024	Exam (NHT)	39	120
2023	Exam	39	120
2023	Exam (NHT)	40	119
2022	Exam	39	120
2021	Exam	39	119
2020	Exam	40	120

Marks by unit

Unit	Share of marks
Unit 3: How can design and innovation help to optimise chemical processes?	51.3%
Unit 4: How are carbon-based compounds designed for purpose?	48.7%

Marks by topic

Topic	Share of marks	Papers it appears in	Years
What are the current and future options for supplying energy?	26.2%	9 of 9	6 of 6
How can the rate and yield of chemical reactions be optimised?	25.1%	9 of 9	6 of 6
How are organic compounds categorised and synthesised?	20.0%	9 of 9	6 of 6
How are organic compounds analysed and used?	19.5%	9 of 9	6 of 6
How is scientific inquiry used to investigate the sustainable production of energy and/or materials?	9.2%	9 of 9	6 of 6

Marks by subtopic

Each topic above breaks into the subtopics below, in the same order.

Subtopic	Share of marks	Papers
Measuring changes in chemical reactions	9.1%	9 of 9
Carbon-based fuels	8.8%	9 of 9
Primary galvanic cells and fuel cells as sources of energy	8.3%	9 of 9
Production of chemicals using electrolysis	11.9%	9 of 9
Extent of chemical reactions	9.7%	9 of 9
Rates of chemical reactions	3.5%	9 of 9
Reactions of organic compounds	10.7%	9 of 9
Structure, nomenclature and properties of organic compounds	9.3%	9 of 9
Instrumental analysis of organic compounds	11.7%	9 of 9
Medicinal chemistry	4.5%	8 of 9
Laboratory analysis of organic compounds	3.3%	5 of 9
Investigation design	4.2%	9 of 9
Scientific evidence	4.1%	9 of 9
Science communication	0.9%	7 of 9

Marks by dot point

Dot-point numbers and wording are VCAA's own. Where a dot point is written as a list, its items run together here separated by semicolons.

Dot point	Content	Topic	Share of marks	Papers
4.1.2.1	organic reactions and pathways, including equations, reactants, products, reaction conditions and catalysts (specific enzymes not required) synthesis of primary haloalkanes and primary alcohols by substitution; addition reactions of alkenes; the esterification between an alcohol and a carboxylic acid; hydrolysis of esters; pathways for the synthesis of primary amines and carboxylic acids; transesterification of plant triglycerides using alcohols to produce biodiesel; hydrolytic reactions of proteins, carbohydrates and fats and oils to break down large biomolecules in food to produce smaller molecules; condensation reactions to synthesise large biologically important molecules for storage as proteins, starch, glycogen and lipids (fats and oils)	How are organic compounds categorised and synthesised?	7.6%	9 of 9
3.2.2.5	calculations involving equilibrium expressions (including units) for a closed homogeneous equilibrium system and the dependence of the equilibrium constant ( $K_c$ ) value on the system temperature and the equation used to represent the reaction	How can the rate and yield of chemical reactions be optimised?	3.5%	9 of 9
4.1.1.4	trends in physical properties within and between homologous series (boiling point and melting point, viscosity), with reference to structure and bonding	How are organic compounds categorised and synthesised?	3.4%	9 of 9
3.2.3.3	the common design features and general operating principles of rechargeable (secondary) cells, with reference to discharging as a galvanic cell and recharging as an electrolytic cell, including the conditions required for the cell reactions to be reversed and the electrode polarities in each mode (details of specific cells not required)	How can the rate and yield of chemical reactions be optimised?	3.3%	9 of 9
3.2.3.5	the application of Faraday’s Laws and stoichiometry to determine the quantity of electrolytic reactant and product, and the current or time required to either use a particular quantity of reactant or produce a particular quantity of product	How can the rate and yield of chemical reactions be optimised?	3.2%	9 of 9
4.1.1.2	molecular, structural and semi-structural (condensed) formulas and skeletal structures of alkanes (including cyclohexane), alkenes, benzene, haloalkanes, primary amines, primary amides, alcohols (primary, secondary and tertiary), aldehydes, ketones, carboxylic acids and non-branched esters	How are organic compounds categorised and synthesised?	3.0%	9 of 9
3.2.3.1	the use and limitations of the electrochemical series to explain or predict the products of the electrolysis of particular chemicals, given their state (molten liquid or in aqueous solution) and the electrode materials used, including the writing of balanced equations (with states) for the reactions occurring at the anode and cathode and the overall redox reaction for the cell	How can the rate and yield of chemical reactions be optimised?	2.7%	9 of 9
4.3.2.2	ways of organising, analysing and evaluating primary data to identify patterns and relationships, including sources of error and uncertainty	How is scientific inquiry used to investigate the sustainable production of energy and/or materials?	2.7%	9 of 9
4.2.3.4	enzymes as protein-based catalysts in living systems: primary, secondary, tertiary and quaternary structures and changes in enzyme function in terms of structure and bonding as a result of increased temperature (denaturation), decreased temperature (lowered activity), or changes in pH (formation of zwitterions and denaturation)	How are organic compounds analysed and used?	2.6%	8 of 9
3.1.2.1	calculations related to the application of stoichiometry to reactions involving the combustion of fuels, including mass-mass, mass-volume and volume-volume stoichiometry, to determine heat energy released, reactant and product amounts and net volume or mass of major greenhouse gases ( $CO_2$ , $CH_4$ and $H_2O$ ), limited to standard laboratory conditions (SLC) at $25\,^\circ\mathrm{C}$ and $100\,\mathrm{kPa}$	What are the current and future options for supplying energy?	2.6%	9 of 9
3.1.2.4	energy from fuels and food calculation of energy transformation efficiency during combustion as a percentage of chemical energy converted to useful energy; comparison and calculations of energy values of foods containing carbohydrates, proteins and fats and oils	What are the current and future options for supplying energy?	2.6%	9 of 9
3.2.1.1	factors affecting the frequency and success of reactant particle collisions and the rate of a chemical reaction in open and closed systems, including temperature, surface area, concentration, gas pressures, presence of a catalyst, activation energy and orientation	How can the rate and yield of chemical reactions be optimised?	2.5%	8 of 9
3.1.3.5	the common design features and general operating principles of fuel cells, including the use of porous electrodes for gaseous reactants to increase cell efficiency (details of specific cells not required)	What are the current and future options for supplying energy?	2.5%	8 of 9
4.2.2.1	applications of mass spectrometry (excluding features of instrumentation and operation) and interpretation of qualitative and quantitative data, including identification of molecular ion peak, determination of molecular mass and identification of simple fragments	How are organic compounds analysed and used?	2.4%	8 of 9
3.2.2.3	the change in position of equilibrium that can occur when changes in temperature or species or volume (concentration or pressure) are applied to a system at equilibrium, and the representation of these changes using concentration-time graphs	How can the rate and yield of chemical reactions be optimised?	2.3%	9 of 9
4.1.2.2	calculations of percentage yield and atom economy of single-step or overall reaction pathways, and the advantages for society and for industry of developing chemical processes with a high atom economy	How are organic compounds categorised and synthesised?	2.1%	8 of 9
3.1.1.6	comparison of exothermic and endothermic reactions, with reference to bond making and bond breaking, including enthalpy changes ( $\Delta H$ ) measured in kJ, molar enthalpy changes measured in $\mathrm{kJ\ mol^{-1}}$ and enthalpy changes for mixtures measured in $\mathrm{kJ\ g^{-1}}$ , and their representations in energy profile diagrams	What are the current and future options for supplying energy?	2.1%	9 of 9
3.1.1.8	combustion (complete and incomplete) reactions of fuels as exothermic reactions: the writing of balanced thermochemical equations, including states, for the complete and incomplete combustion of organic molecules using experimental data and data tables	What are the current and future options for supplying energy?	2.1%	9 of 9
4.2.2.4	structural determination of organic compounds by low and high resolution proton nuclear magnetic resonance ( $^1\mathrm{H}$ -NMR) spectral analysis, using chemical shift values, integration curves (where the height is proportional to the area underneath a peak) and peak splitting patterns (excluding coupling constants), and application of the $n+1$ rule (where $n$ is the number of neighbouring protons) to deduce the number and nature of different proton environments	How are organic compounds analysed and used?	2.1%	9 of 9
3.1.2.2	the use of specific heat capacity of water to approximate the quantity of heat energy released during the combustion of a known mass of fuel and food	What are the current and future options for supplying energy?	2.1%	9 of 9

These 20 dot points carry 57.4% of the paper marks between them. Another 46 assessed dot points share the rest, and 2 of the 68 externally assessable dot points have not been assessed in any of these 9 papers. Content that has not appeared is still examinable.

What has moved between papers

No topic's share moved by more than 3.0 percentage points between the 2020 to 2022 papers and the 2023 to 2025 papers. The largest movement was 1.4 points, which is inside the range two papers a year produce by chance, so nothing here is a trend to revise around.

How the papers are built

Short answer carries 74.4% of the marks across these 9 papers.

Question type	Share of marks	Marks	Parts
Short answer	74.4%	802	459
Multiple choice	25.0%	270	270
Extended response	0.6%	6	1

Verb	Share of marks	Marks	Parts
explain	18.3%	197	82
calculate	12.5%	135	53
state	7.7%	83	67
identify	7.1%	76	51
write	6.9%	74	59
justify	4.5%	48	21
draw	4.0%	43	29
discuss	3.6%	39	12

What these percentages do not tell you

Where to practise

Every topic above links to its own page of real VCAA questions with marking criteria and average scores attached: What are the current and future options for supplying energy?, How can the rate and yield of chemical reactions be optimised?, How are organic compounds categorised and synthesised?, How are organic compounds analysed and used? and How is scientific inquiry used to investigate the sustainable production of energy and/or materials?. For how students actually score on this content, read VCE Chemistry hardest topics, and for the full question bank start at VCE Chemistry.

Syllabus and assessment material referenced in this guide is reproduced by permission, © VCAA. See our VCAA licensing notice. The VCAA does not endorse or make any warranties regarding this study resource. VCE® is a registered trademark of the VCAA.