Which QCE Chemistry past paper do students score lowest on?

The 2021 Paper 2, averaging 52.3% across 237 marked attempts on AusGrader. The 2024 Paper 1 is the highest on 70.1%.

Which QCE Chemistry dot points give the best return on revision time?

3.1.2.3 (1.8 marks at risk per 100), 3.2.4.6 (1.5 marks at risk per 100) and 4.2.1.2 (1.4 marks at risk per 100). Marks at risk combines a dot point's share of paper marks with the marks students drop on it, so it ranks by recoverable marks and not by score alone.

How many attempts is each QCE Chemistry figure based on?

41,173 marked attempts overall, with the per-row count shown in every table. Any cut below 50 attempts is withheld instead of published.

Do these averages show how the QCAA cohort performed?

No. They are AusGrader users' marked attempts, a self-selected group practising when they chose to and often without exam timing. They corroborate what QCAA publishes about this subject and do not replace it.

QCE Chemistry hardest topics

Across 41,173 marked attempts on AusGrader, QCE Chemistry students average 58.9% on questions taken from board external papers. The lowest average of any command verb is draw on 54.1%, and the verb that costs the most marks is explain, which carries 33.7% of the paper against 1.8% for draw. These are self-selected users practising when they chose to, not the QCAA cohort under exam conditions.

How to read these numbers

The figures are AusGrader users' marked attempts, not QCAA results. They corroborate what the board publishes about this subject and do not stand in for it.
Any cut with fewer than 50 attempts is withheld, which on this page is 21 dot points and 19 verbs. Every figure shown carries its attempt count.
Scores cover questions mapped to the QCE Chemistry syllabus from any board's external papers, which is why the sample is larger than the 12 QCAA papers alone. The paper table below is the exception and uses QCAA papers only.
Internal assessment and school-uploaded exams are excluded throughout, so these averages differ from the ones on QCE Chemistry performance stats, which count every attempt.

Score by past paper

Year	Paper	Average	Attempts
2025	Paper 1	66.4%	1,225
2025	Paper 2	63.7%	192
2024	Paper 1	70.1%	1,263
2024	Paper 2	59.9%	367
2023	Paper 1	64.6%	867
2023	Paper 2	65.9%	377
2022	Paper 1	57.2%	1,042
2022	Paper 2	56.3%	202
2021	Paper 1	69.1%	939
2021	Paper 2	52.3%	237
2020	Paper 1	64.0%	788
2020	Paper 2	69.4%	101

The lowest average belongs to the 2021 Paper 2 on 52.3% from 237 attempts, and the highest to the 2024 Paper 1 on 70.1% from 1,263 attempts. A paper's average reflects both how hard it was and who chose to sit it, so treat the spread as a guide to which papers make demanding practice.

Score by question type

Question type	Average	Attempts
Extended response	46.4%	98
Multiple choice	57.4%	34,283
Short answer	62.5%	6,792

Score by unit

Unit	Average	Attempts
Unit 3: Equilibrium, acids and redox reactions	58.5%	21,511
Unit 4: Structure, synthesis and design	58.9%	16,903

An attempt counts once per unit, so a question assessed across two units appears in both rows and the column adds to slightly more than 41,173.

The priority list: heavy topics with low scores

Topic	Share of marks	Average	Attempts	Marks at risk
Chemical equilibrium systems	39.0%	61.1%	13,342	15.2
Properties and structure of organic materials	28.9%	58.9%	13,889	11.9
Oxidation and reduction	20.2%	53.1%	8,390	9.5
Chemical synthesis and design	12.0%	58.8%	4,033	4.9

Chemical equilibrium systems tops the list on 15.2 marks at risk per 100 paper marks, 3.3 ahead of Properties and structure of organic materials.

The same cut at subtopic level

Subtopic	Share of marks	Average	Attempts	Marks at risk
Redox reactions	8.1%	49.3%	2,602	4.1
Structure of organic compounds	9.7%	61.5%	4,703	3.7
Chemical synthesis	7.7%	57.2%	2,793	3.3
Standard electrode potential	6.1%	46.6%	1,929	3.3
Organic reactions and reaction pathways	8.7%	63.2%	4,133	3.2
Factors that affect equilibrium	6.6%	56.7%	3,859	2.9
Equilibrium constants	5.7%	59.8%	1,999	2.3
Analytical techniques	4.2%	50.3%	2,243	2.1
Dissociation constants	6.3%	67.9%	521	2.0
Volumetric analysis	4.6%	56.2%	1,702	2.0
Organic materials: structure and function	4.1%	58.5%	1,944	1.7
Acid-base indicators	2.9%	45.1%	317	1.6
Macromolecules: polymers, proteins and carbohydrates	4.2%	64.0%	1,240	1.5
Electrolytic cells	3.1%	51.5%	1,849	1.5
Chemical equilibrium	3.7%	64.4%	5,232	1.3

The same cut at dot-point level

Dot point	Content	Share of marks	Average	Attempts	Marks at risk
3.1.2.3	Apply Le Châtelier’s principle to determine the effect changes of temperature, concentration of chemicals, pressure and the addition of a catalyst have on the position of equilibrium and on the value of the equilibrium constant	4.3%	57.7%	3,351	1.8
3.2.4.6	Analyse data, including standard electrode potentials, to make predictions about the spontaneity of a reaction and to compare electrochemical cells	2.7%	44.6%	1,723	1.5
4.2.1.2	Describe, using equations, the: production of ammonia by the Haber process; production of sulfuric acid using the contact process; production of ethanol from fermentation and the hydration of ethene; operation of a hydrogen fuel cell under acidic and alkaline conditions	3.4%	59.5%	1,250	1.4
3.1.7.4	Calculate dissociation constants ( $K_a$ , $K_b$ , and $K_w$ ), $pK_a$ , $pK_b$ , and the concentrations of reactants and products. (Formula: $K_a = \frac{[H_3O^+][A^-]}{[HA]}$ ; $K_b = \frac{[BH^+][OH^-]}{[B]}$ ; $K_w = K_a \times K_b$ )	4.1%	68.7%	217	1.3
3.1.3.6	Calculate equilibrium constants ( $K_c$ ) and the concentrations of reactants and products. Assume $[reactants]_{initial} = [reactants]_{equilibrium}$ when $K_c$ is very small and state assumption when used. (Formula: $K_c = \frac{[C]^c[D]^d}{[A]^a[B]^b}$ for the reaction $aA + bB \rightleftharpoons cC + dD$ )	2.6%	52.6%	1,198	1.2
3.2.1.2	Determine the species oxidised and reduced, and the oxidising agent and reducing agent, in redox reactions	2.1%	50.2%	1,703	1.1
3.2.1.7	Analyse data, including displacement reactions of metals, combustion, corrosion and electrochemical processes to determine redox reactions	1.7%	40.1%	336	1.0
3.2.1.3	Explain that oxidation can be modelled as the loss of electrons from a chemical species, and reduction can be modelled as the gain of electrons by a chemical species; these processes can be represented using balanced half-equations and redox equations (acidic conditions only)	1.8%	44.1%	766	1.0
4.2.1.3	Calculate the yield of chemical synthesis reactions by comparing stoichiometric quantities with actual quantities and by determining limiting reagents and/or reaction conditions	2.2%	54.7%	730	1.0
4.1.4.1	Describe the structural features of: amino acids, tripeptides, monosaccharides and disaccharides; polyethene (LDPE and HDPE), polypropene (syntactic, isotactic and atactic) and polytetrafluorethene (Teflon); polylactic acid (PLA), polyamide (nylon) and polyester	2.6%	62.1%	1,630	1.0
4.1.5.4	Analyse data from spectra, including mass spectroscopy and infrared to determine the identity and structure of organic molecules	2.0%	50.7%	1,797	1.0
3.2.5.5	Explain the products of the electrolysis of aqueous solutions, e.g. dilute and concentration sodium chloride(aq) and copper sulfate(aq)	1.6%	38.9%	550	1.0
3.1.9.5	Analyse volumetric data, including solubility, conductometric and acid-base titration curves, to determine moles, mass, volume and concentration	2.1%	53.7%	1,421	1.0
4.2.2.1	Describe, using equations, how: addition polymers, including polyethene (LDPE and HDPE), polypropene and polytetrafluorethene, can be produced from their monomers; condensation polymers, including polysaccharides (carbohydrates), polylactic acid (PLA), polyamide (proteins and nylon) and polyester, can be produced from their monomers	2.5%	63.1%	678	0.9
4.1.2.1	Explain the trends (melting point, boiling point, volatility, solubility in water and organic solvents) within and between homologous series (alkanes, alkenes, alcohols, carboxylic acids) in term of intermolecular and intramolecular bonding, e.g. dispersion forces, dipole-dipole interactions and hydrogen bonds	2.0%	55.7%	1,622	0.9
3.2.4.4	Calculate cell potential, $E^o_{cell}$ (Formula: $E^o_{cell} = E^o_{reduction\ half-cell} - E^o_{oxidation\ half-cell}$ )	1.6%	47.8%	936	0.8
3.1.5.3	Calculate pH, hydrogen ion concentration $[H^+(aq)]$ , pOH and hydroxide ion concentrations $[OH^-(aq)]$ for strong acids and bases. (Formula: $pH = -\log_{10} [H^+]$ and $pOH = -\log_{10}[OH^-]$ )	2.5%	68.9%	534	0.8
3.2.3.5	Identify the essential components of a galvanic cell, including the oxidation and reduction half-cells, the positive and negative electrodes and their solutions of their ions, the flow of electrons and the movement of ions, and the salt bridge	1.6%	52.6%	1,153	0.8
4.1.1.6	Determine molecular and structural formulas for organic compounds, up to $C_{10}$ , including simple methyl and ethyl branched chains, for: alkanes, alkenes and alkynes; alcohols (primary, secondary and tertiary); aldehydes and ketones; carboxylic acids; amines and amides; haloalkanes (primary, secondary and tertiary); esters	1.8%	57.7%	1,774	0.8
4.1.1.1	Identify organic molecules including alkanes, alkenes, alkynes, alcohols, aldehydes, ketones, carboxylic acids, haloalkanes, esters, amines and amides	1.8%	58.4%	667	0.8

Which command verbs cost the most marks

Verb	Share of marks	Average	Attempts	Marks at risk
explain	33.7%	60.1%	2,223	13.4
determine	19.1%	63.1%	1,010	7.0
calculate	12.0%	61.4%	715	4.6
identify	11.8%	61.7%	1,114	4.5
predict	6.1%	62.1%	240	2.3
apply	4.9%	63.5%	209	1.8
describe	5.2%	65.7%	227	1.8
deduce	3.6%	62.3%	193	1.4
draw	1.8%	54.1%	454	0.8

Draw has the lowest average on the page at 54.1%, and it is not where the marks go. Explain averages 60.1% but carries 33.7% of the paper against 1.8%, so it puts 13.4 marks per 100 at risk against 0.8. For the plain ranking of verbs by score, and what QCAA has said about each, read the QCE Chemistry study guide.

What this does not measure

Where to practise

Work the priority list from the top: Chemical equilibrium systems and Properties and structure of organic materials first, then the dot points above. Each topic page holds real QCAA questions with marking criteria attached. For what the papers actually cover, read QCE Chemistry most tested topics.

Syllabus and assessment material referenced in this guide is © State of Queensland (Queensland Curriculum and Assessment Authority), licensed under CC BY 4.0. See our QCAA licensing notice. AusGrader is an independent study tool and is not affiliated with, endorsed by, or operated by the QCAA.